Running head: EVALUATION OF ANTICOAGULATION CLINIC
Program Evaluation of a Nurse-Managed Anticoagulation Clinic Protocol
Nathan W. Samuels
Doctor of Nursing Practice Capstone
Simmons College
Author Note
Nathan W. Samuels, School of Nursing and Health Sciences, Simmons College.
Correspondence concerning this article should be addressed to Nathan W. Samuels,
Department of Nursing, Simmons College, 300 The Fenway, Boston, MA 02115. E-mail:
© 2011 Nathan W. Samuels
EVALUATION OF ANTICOAGULATION CLINIC ii
The Capstone Manuscript of Nathan W. Samuels entitled
Program Evaluation of a Nurse-Managed Anticoagulation Clinic Protocol
in partial fulfillment of the requirements for the degree of
Doctor of Nursing Practice
in the School of Nursing and Health Sciences at Simmons College
has been read and approved by the Capstone Committee:
_________________________________________
First Chair: Susan Duty, Sc.D., ANP-BC
_________________________________________
Second Chair: Patricia White, Ph.D., ANP-BC
_________________________________________
Third Chair: David E.Schwartz, M.D.
_________________________________________
Program Director: Susan Neary, Ph.D., ANP-BC
Date:____________________
EVALUATION OF ANTICOAGULATION CLINIC iii
Abstract
Nurse-managed anticoagulation programs are employed to provide safe and effective
management of anticoagulant therapy. There is no standardization of dosing protocols for
the nurses who manage this therapy, and various treatment algorithms have been developed,
each with its own benefits and limitations. Despite flexibility within dosing protocols, nurses
encounter situations in which they feel the algorithm directs them inappropriately. The
situations where nurses challenge the validity of protocols are not well understood or defined
in the literature. This program evaluation project studied an existing anticoagulation protocol
and identified clinical issues in the nurses‟ critical thinking processes that lead to clinical
dissonance through a series of focus groups and a comprehensive clinical audit. The process
exposed numerous clinical management issues within the existing anticoagulation protocol,
and then recommended evidence-based solutions from the findings in the literature and from
the outcomes data collected through the audit with the goal of improving the safety and
effectiveness of the clinic.
EVALUATION OF ANTICOAGULATION CLINIC iv
Acknowledgements
I would like to acknowledge the countless hours of work and the incredible support of all the
members of my capstone committee. Without their tireless commitment to the success of
this project, this capstone would not have been possible.
The clinic nurses and medical assistants have my deepest thanks for all of their efforts to
make this project a success, and for their investment in the process of program improvement.
Special thanks are in order to Ilana Steinhauer for her assistance and support in this project.
She went above and beyond her nursing and student responsibilities for this project. Her
dedication to this project is a testament to her professionalism and commitment to the field of
nursing.
Lastly, but very importantly, I would like to thank my family, classmates, and friends for
their encouragement, understanding, and support thought this process. The process of
becoming a DNP would not have been possible without you all.
EVALUATION OF ANTICOAGULATION CLINIC v
Table of Contents
Introduction ............................................................................................................................................ 1
Background Knowledge ...................................................................................................................... 2
Warfarin pharmacology. ................................................................................................................. 2
Anticoagulation clinics. ................................................................................................................... 3
Cost and efficacy............................................................................................................................. 6
Scope of practice. ........................................................................................................................... 7
Variability in practice. ..................................................................................................................... 9
Critical-thinking process. .............................................................................................................. 11
Organizational setting. ................................................................................................................. 14
Problem ............................................................................................................................................ 16
Intended Improvement .................................................................................................................... 17
Study Questions................................................................................................................................ 18
Methods ............................................................................................................................................... 19
Sample .............................................................................................................................................. 19
Setting............................................................................................................................................... 20
Planning ............................................................................................................................................ 20
Focus groups. ................................................................................................................................ 23
Audit tool development. .............................................................................................................. 24
Analysis ............................................................................................................................................. 26
Focus group analysis. .................................................................................................................... 26
Clinic audit analysis. ..................................................................................................................... 27
Second focus group analysis. ........................................................................................................ 28
Ethical Issues .................................................................................................................................... 28
Results .................................................................................................................................................. 29
Outcomes of Focus Group ................................................................................................................ 29
Medication interactions. .............................................................................................................. 30
New to wafarin/suspension of therapy. ....................................................................................... 30
Trending/history. .......................................................................................................................... 31
Dosing calculator ineffective. ....................................................................................................... 32
High-risk/concerning factors. ....................................................................................................... 33
EVALUATION OF ANTICOAGULATION CLINIC vi
Patient factors and extraneous factors. ....................................................................................... 33
Group standard. ........................................................................................................................... 35
Summary of focus group findings. ................................................................................................ 35
Methodological considerations. ................................................................................................... 36
Outcomes of Practice Audit .............................................................................................................. 37
Description of sample. .................................................................................................................. 38
Medication interactions. .............................................................................................................. 41
New to warfarin/suspension of therapy. ..................................................................................... 42
Trending/history. .......................................................................................................................... 42
Dosing calculator ineffective. ....................................................................................................... 43
High-risk/concerning factors. ....................................................................................................... 43
Patient factors and extraneous factors. ....................................................................................... 44
Group standard. ........................................................................................................................... 45
Previously unidentified issues. ..................................................................................................... 47
Limitations. ................................................................................................................................... 50
Outcomes of Second Focus Group ................................................................................................... 52
Agreement with findings. ............................................................................................................. 53
Documentation hindrances. ......................................................................................................... 55
EMR deficiencies........................................................................................................................... 56
Routinized patterns of behavior. .................................................................................................. 57
Summary of second focus group findings. ................................................................................... 58
Discussion and Recommendations for Change .................................................................................... 58
Medication interactions. .............................................................................................................. 60
New to warfarin/suspension of therapy. ..................................................................................... 62
Trending/history. .......................................................................................................................... 63
Dosing calculator ineffective. ....................................................................................................... 65
High-risk/concerning factors. ....................................................................................................... 66
Patient factors and extraneous factors. ....................................................................................... 67
Group standard. ........................................................................................................................... 67
Previously unidentified issues. ..................................................................................................... 70
Summary and recommendations. ................................................................................................ 71
Process Improvement Recommendations ........................................................................................... 73
EVALUATION OF ANTICOAGULATION CLINIC vii
Tracking and quality assurance. ................................................................................................... 73
Documentation of care. ................................................................................................................ 73
Protocol revisions. ........................................................................................................................ 73
Areas for nursing staff and clinic development. ........................................................................... 73
Proposed Phases of Implementation ................................................................................................... 74
Tables and Graphics ............................................................................................................................. 75
Table 1 .............................................................................................................................................. 75
Table 2 .............................................................................................................................................. 76
Table 3 .............................................................................................................................................. 80
Table 4 .............................................................................................................................................. 81
Table 5 .............................................................................................................................................. 82
Table 6 .............................................................................................................................................. 83
Table 7 .............................................................................................................................................. 84
Table 8 .............................................................................................................................................. 85
Table 9 .............................................................................................................................................. 88
Figure 1 ............................................................................................................................................. 89
Figure 2 ............................................................................................................................................. 90
Appendices ........................................................................................................................................... 91
Appendix A: Timeline of Events ........................................................................................................ 91
Appendix B: Informed Consent ........................................................................................................ 92
Appendix C: Confidentiality Agreement ........................................................................................... 93
Appendix D: Focus Group Guide (Session 1) .................................................................................... 94
Appendix E: Existing Protocol ........................................................................................................... 95
Appendix G: Audit Tools ................................................................................................................. 106
References .......................................................................................................................................... 107
EVALUATION OF ANTICOAGULATION CLINIC 1
Introduction
Successful systemic anticoagulation, specifically with warfarin, requires careful
monitoring, assessment, and adjustment of medication therapy. Anticoagulation Clinics have
been developed in various practice settings to help manage the substantial and growing
volume of patients receiving anticoagulant therapy. Hematology, Oncology, Cardiology,
Orthopedic, and Primary Care practices often utilize Anticoagulation Clinics to monitor and
adjust warfarin dosing for their patients. Treatment protocols and algorithms lack
standardization from institution to institution, and the credentialing of the providers who
manage therapy is also diverse (Ebell, 2005 & Francavilla, 2008). Clinics will often employ
the services of registered nurses (RNs), pharmacists, nurse practitioners, and physician
assistants for delivery of anticoagulant therapy services.
A major safety goal from The Joint Commission (2007) called for the reduction in the
likelihood of patient harm associated with the use of anticoagulant therapy. This program
evaluation project was commissioned the Medical Director of a nurse-managed
anticoagulation clinic to determine the current status and needs of the service. The project
analyzed the utility, reliability, and safety of the existing nurse-managed anticoagulation
protocol; examined the critical thinking processes employed by the nurses using the protocol;
and identified deficiencies in the protocol that required additional attention. Evidence-based
recommendations for change were provided, and ongoing performance-tracking measures
were established.
EVALUATION OF ANTICOAGULATION CLINIC 2
Background Knowledge
Anticoagulation management is a process by which patients are placed on blood-
thinning agents (anticoagulants) with the goal of preventing thrombotic and embolic events
in patients with various diagnoses and high-risk conditions (Baglin, Keeling, & Watson,
2005). A common method for providing anticoagulation therapy is through the use of
warfarin, an oral prescription medication. Warfarin therapy requires careful monitoring and
dose adjustment to maintain patients within a goal therapeutic range of coagulation measures.
The following review of literature will summarize the state of the science relating to warfarin
therapy care models, and evidence-based means to promote patient safety while providing
this therapy.
Warfarin pharmacology. The anticoagulant effect of warfarin is mediated through
inhibition of vitamin K-dependent coagulation factors, including clotting factors II, VII, IX,
and X (Valentine & Hull, 2009). Warfarin is rapidly absorbed in the GI tract, circulates
bound to plasma proteins, and has a half-life of 36 to 42 hours (Hirsh, Fuster, Ansell, &
Halperin, 2003). Warfarin is a racemic mixture of S and R enantiomers, and the more potent
S form of the drug is metabolized primarily by the hepatic CYP2C9 system. Because this
enzyme system is inducible by many drugs and has a number of genetic variants, warfarin's
activity is highly variable in individual patients (Valentine & Hull, 2009). Variable amounts
of dietary intake of vitamin K will have an effect on warfarin dosing, as will alterations in
vitamin-K producing intestinal flora (Conly & Stein, 1992). Also, because warfarin is
strongly protein-bound and only the non-protein-bound fraction is biologically active, any
substance that binds to albumin may displace warfarin from its albumin binding sites and
increase its biological activity (Valentine & Hull, 2009).
EVALUATION OF ANTICOAGULATION CLINIC 3
The prothrombin time (PT) responds to reduction of 3 of the 4 vitamin K-dependent
procoagulant clotting factors that are reduced by warfarin (Hirsh, Fuster, Ansell, & Halperin,
2003), and is therefore a surrogate marker of the anticoagulation effect exhibited by the
therapy. The International Normalized Ratio (INR) is the ratio of an individual‟s
prothrombin time to a control sample, raised to the power of the International Sensitivity
Index (Hirsh, Fuster, Ansell, & Halperin, 2003). Thus, the INR is a standardized value for a
patient‟s clotting time. The INR is used to gauge the level of anticoagulation on warfarin
therapy, and is tracked following dosing adjustments.
Anticoagulation clinics. Due to the labor-intensive nature of managing warfarin
therapy, anticoagulation clinic models have been developed in various settings to provide a
centralized service for patients receiving therapy. Rather than having regular monitoring and
dose adjustments performed on a case-by-case basis by a patient‟s medical provider, an
anticoagulation service will assume responsibility for managing therapy. By centralizing
care, the evidence suggests that anticoagulation clinics produce improved patient outcomes
over usual physician-managed care (Nichol, Knight, Dow, Wygant, Borok, Hauch, Hauch,
O‟Connor, 2008).
A meta-analysis of 67 studies involving 50,208 anticoagulated patients found that
study setting (i.e. organizational style for anticoagulation management) had the greatest
effect on anticoagulation control with studies in community practices having significantly
lower control than anticoagulation clinics (van Walraven, Jennings, Oake, Fergusson, &
Forrester, 2006). In this analysis, INR was in therapeutic range an average of 66% of the
time for patients in anticoagulation clinics, and only 57% of the time in patients managed by
community physicians.
EVALUATION OF ANTICOAGULATION CLINIC 4
Numerous models have been developed for anticoagulation clinics, employing the
services of various medical professionals, including physicians, nurse practitioners, physician
assistants, pharmacists, and registered nurses (RNs). RN-managed anticoagulation programs
have been developed because of the numerous beneficial skill-sets possessed by nurses
(Shimbukuro & Kramer, 2004). RNs are able to collect pertinent patient history, symptoms,
and clinical exam findings; determine clinical relevance of their findings; and formulate a
care plan. Additionally, nurses are able to provide patient education, which is critical to the
success of anticoagulant therapy (Wofford, Wells, & Singh, 2008). Unlicensed technical
support personnel cannot be involved in patient assessment or therapy management (Garcia,
Witt, Hylek, Wittkowsky, Nutescu, Jacobson, et al., 2008). In terms of financing, RNs also
are desirable to practices because of their ability to bill for services, and their relatively lower
salaries as compared to other providers.
The dilemma RN-managed anticoagulation programs face is the scope-of-practice
limitation of RNs related to the adjustment of prescription medications. As RNs (without
advanced practice standing) do not have prescriptive authority, they must operate under
standing-orders or sliding-scales. These orders must be comprehensive enough to allow for
patient-specific dosing without being so loose that they are beyond the nurses‟ scope of
practice regulations. If protocols are overly restrictive, the clinic is less independent and
requires more prescriber involvement.
As warfarin dosing is highly individualized, a carefully tailored plan is necessary for
each patient at each follow-up visit. Specially designed dosing-calculators that recommend
dose adjustments based solely upon an INR value are based on generalizations of predicted
effects of incremental dose changes. These calculators do not have the capacity to take into
EVALUATION OF ANTICOAGULATION CLINIC 5
account clinically relevant medication interactions or other significant patient-specific
variables (Niiranen & Yli-Hietanen, 2008). As a result, anticoagulation protocols will often
incorporate a dosing calculator into a flexible algorithm that allows for provider discretion.
Protocols for nurse-managed anticoagulation clinics not only need to incorporate
guidelines for dosing adjustments, they must also provide standards for frequency of
monitoring. The algorithms must therefore integrate dosing recommendations with return-to-
clinic instructions. As the complexity of the clinical situation increases, so do the
opportunities for clinical concerns with a dosing protocol. With these dual
recommendations, the nurse may find fault with the dose recommendation, the return-to-
clinic recommendation, or both.
Shimbukuro and Kramer (2004) studied the use of a decision support system utilized
by nurses in an anticoagulation clinic for warfarin dosing determinations. The authors
reported only 86.4% of dose adjustments by nurses were done “correctly” by the nurses
according to the guidelines. Thus, these clinic nurses would legally be required to consult
with a provider for these 13.6% of cases that are dosed outside of protocol. This also
suggests that there may be cases where the nurses sought prescriber consultation that did not
result in a variation from protocol. Previous studies that have demonstrated the safety and
effectiveness of nurse-managed anticoagulation protocols and effectiveness of various dosing
algorithms have not investigated the level of prescriber involvement required to support a
protocol (e.g., Anderson, Wilson, Blundell, Petrie, Leighton, Stanish, et al., 2002;
Shimbukuro & Kramer, 2004)
The decision to vary from protocol is one made from careful clinical assessment skills
and knowledge of warfarin pharmacodynamics. Studies, such as Shimbukuro and Kramer
EVALUATION OF ANTICOAGULATION CLINIC 6
(2004), which demonstrate nursing deviation from protocol would suggest that there exists a
clinical assessment process that evaluates the appropriateness of a dosing protocol on an
ongoing basis. The situations that prompt this disagreement with a dosing protocol are not
well understood or described in the literature. Better identification of the key issues that
cause a nurse to question a protocol may allow for improvements to the anticoagulation clinic
systems.
Cost and efficacy. The costs associated with anticoagulation care can be measured
in terms of both direct and indirect costs. Operating costs of the clinic, including facilities,
staff, supplies, and other overhead, are included in the direct costs. The costs to the patients
and insurers are related to the charges for provider services, testing services, and medication.
All of these costs incurred by the patients and insurers are affected by the frequency of
testing and need for dosing adjustments. The added costs to the patients are related to time
and money lost by additional appointments with associated travel costs and missed work.
Major indirect costs to the system are related to the adverse outcomes associated with
poorly managed anticoagulation; specifically, adverse outcomes related to sub-therapeutic or
supra-therapeutic INRs. In a meta-analysis by Oake, Fergusson, Forster, and van Walraven
(2007), the data revealed that critically high anticoagulation intensity (defined by an INR
higher than target range) explained 25.6% of all serious events in anticoagulated individuals.
Additionally, critically low anticoagulation intensity (defined as an INR lower than target
range) explained 11.1% of all serious thromboembolic events. The researchers concluded
that improved anticoagulation control could decrease the likelihood of almost half of all
anticoagulant-associated adverse events. The financial implications of improving the
accuracy of a dosing protocol are therefore substantial.
EVALUATION OF ANTICOAGULATION CLINIC 7
In reviewing the effectiveness of a nurse-managed anticoagulation clinic, Connor,
Wright, and Fegan (2002) found no statistically significant difference in anticoagulation
control between consultant hematologists and anticoagulant nurses, but did find that patients
attended clinics on significantly fewer occasions with nurse-led management. In other
words, these findings suggest that the nurses were able to maintain patients within target-
range equally as well as the hematologists, but were able to do so with fewer visits.
Furthermore, these findings would support the reduced costs to patients and insurers
associated with RN-managed clinics as compared to other models.
Chiquette, Amato, & Bussey (1998) found a savings of $1,621 per patient-year of
therapy in their comparative study of anticoagulation management services versus usual care
due to a significant reduction in hospitalizations and emergency department visits. Wilt,
Gums, Ahmed, & Moore (1995) found a savings of $4,072 per patient-year of therapy with
an anticoagulation service due to reduced utilization of emergency services. Although these
studies have limitations due to design and sample sizes, their findings support the significant
cost-savings that is possible through improved anticoagulation management.
Scope of practice. Shimbukuro and Kramer (2004) studied the use of a decision
support system utilized by nurses in an anticoagulation clinic for warfarin dosing
determinations. The authors reported only 86.4% of dose adjustments by nurses were done
“correctly” by the nurses according to the guidelines. The specifics of the 13.6% of cases
that were not managed according to the guidelines are not provided in this study. The study
did not specify whether or not there was a similar, increased, or decreased rate of adverse
events associated with the cases that were not managed according to the guidelines.
Nevertheless, these findings support the general belief that there are always cases that do not
EVALUATION OF ANTICOAGULATION CLINIC 8
fall within a dosing algorithm. In Shimbukuro and Kramer‟s study, it would stand to reason
that based upon some unknown factors obtained by the nurses‟ assessments, the nurses
determined that the dosing protocol was not appropriate for these patients. The specifics of
these situations are not fully understood, nor are the decision-making processes by which the
nurses made the determination that the protocol was inappropriate.
Under typical nurse practice acts, RNs do not have the authority to adjust a
medication dosage without specific guidelines from a licensed prescriber, and unique clinic
characteristics and structural elements are influenced by external and internal regulatory
requirements as well as state and federal laws (Garcia, Witt, Hylek, Wittkowsky, Nutescu,
Jacobson, et al., 2008). Operating under a dosing algorithm or protocol, RNs may only
instruct patients to modify dosing based upon the written policy that details the specifics of a
dose change. A “clinical judgment call” by which a provider determines an alternate
medication dose is not within the scope of practice of an RN unless there are specific
protocols that govern this determination. Legal liability issues with variations from protocols
and automated clinical pathways have received increasing amounts of attention as more of
these systems have been developed (e.g. Brugh, 1998). In considering scope of practice
limitations of RNs in Shimbukuro and Kramer‟s study, all 13.6% of the cases where warfarin
doses are adjusted outside of a protocol legally must be approved by another licensed
provider.
Shimbukuro and Kramer did not examine cases where the nurse may have questioned
the appropriateness of a dose adjustment recommended by the protocol, and sought the
advice of another provider. Presumably, there were additional cases that fell within this type
of situation that were not captured by the study because the ultimate dosing recommendation
EVALUATION OF ANTICOAGULATION CLINIC 9
fell within the protocol‟s range. For instance, a nurse may have questioned the protocol,
sought the advice of a provider, and ultimately dosed a patient as the protocol recommended.
In this example, the study would not have reported that the nurse did not follow the protocol
appropriately, and there would be no record of the nurse having to seek assistance.
Therefore, productivity and clinical-independence are not fully appreciated by the measures
employed in previous studies.
The aspects of clinical decision-making by registered nurses that prompt a nurse to
seek support and possibly stray from an anticoagulation protocol are not well-defined in the
existing literature. The effect of these decisions is presumed to result in improved patient
outcomes; however, the opposite may also be true. Prior evidence has demonstrated that
physician-managed anticoagulation may be inferior to anticoagulation managed by clinics
(Chiquette, Amato & Bussey, 1998; van Walraven, Jennings, Oake, Fergusson & Forster,
2006). It remains unknown as to which aspects of care delivery result in this difference.
Another confounder in the analysis of these data is that anticoagulation clinics have
different collaborative arrangements with physicians depending on the setting. In some
cases, clinics will use an expert hematologist or cardiologist for decision support, and in
others, clinic nurses will rely upon a variety of providers. The effects of having prescriber
consultants of various backgrounds within a single clinic have not been examined in previous
studies (e.g. Connor, Wright, & Fegan, 2002).
Variability in practice. The structure of nurse-managed anticoagulation clinics
varies based on practice setting, and is also affected by the indications for therapy. For
example, some dosing algorithms are specific to orthopedic procedures, and others are
tailored for diagnoses of atrial fibrillation, mechanical heart valves, pulmonary emboli, etc.
EVALUATION OF ANTICOAGULATION CLINIC 10
Some protocols utilize a graphic nomogram for dosage adjustment (Dalere, Coleman & Lum,
1999), and others utilize a dosage adjustment worksheet (Shimabukuro, Kramer & McGuire,
2004). Also, nomograms have variable dosing recommendations and return-to-clinic
recommendations (Kovacs, Rodger, Anderson, Morrow, Kells, Kovacs, et al., 2003).
At present, there is no standard of care, and there are no standard operating
procedures for all nurse-managed anticoagulation clinics. Clinics are structured differently
and employ various dosing protocols for the nurses to utilize in patient care. The major
safety goal of reduction in the likelihood of patient harm associated with the use of
anticoagulation therapy that was put out by The Joint Commission (2007) has left individual
institutions to devise unique anticoagulation programs that best serve their practice areas and
work with their available resources.
The Anticoagulation Forum (Garcia et al., 2008) published a consensus statement
related to optimized anticoagulant therapy. Within this statement, the authors described
various characteristics of anticoagulation programs that should be considered as “best
practices.” In this statement, the supervisory practice agreement qualities are described. The
authors commented, “Optimized anticoagulation therapy is provided by a dedicated
[Anticoagulation Management Service] in numerous healthcare settings, each with unique
characteristics and structural elements and influenced by internal and external regulatory
requirements as well as state and federal law” (p. 980).
The decision-making process by which nurses make the determination that a protocol
dose recommendation may be inappropriate is not fully understood, and the situations that
prompt these determinations have not been characterized. The effects of a dosing protocol
that only allows for small dosing adjustments within a narrow range of INRs span from
EVALUATION OF ANTICOAGULATION CLINIC 11
decreased nurse-independence and clinic utility to higher costs on the health care system due
to inefficient management practices. Additionally, a dosing protocol that allows for more
variability in dosing adjustments based upon clinic data places a higher level of responsibility
upon the nurse and relies more heavily upon his or her skill-level, and may be limited based
upon state nursing practice acts.
Critical-thinking process. Benner and Tanner (1987) wrote, “Intuition has seldom
been granted legitimacy as a sound approach to clinical judgment. Instead, it has been
viewed as the basis for irrational acts or guessing, as unfounded knowledge, or even as
supernatural inspiration. In fact, intuition appears to be a legitimate and essential aspect of
clinical judgment” (p. 23). Within this article, the authors explored Dreyfus‟s six key aspects
of intuitive judgment: pattern recognition, similarity recognition, commonsense
understanding, skilled know-how, sense of salience, and deliberative rationality. These six
aspects of intuitive judgment may be recognized in the nurse decision-making process.
Within their discussion, Benner and Tanner asked the question, “Can we teach intuition?” (p.
31).
Benner (1982) explored the Dreyfus Model of Skill Acquisition as a nurse develops
through the five levels of proficiency: novice, advanced beginner, competent, proficient, and
expert. In her assessment of the nurse‟s progression from Novice though the stages to
Expert, Benner concluded the following:
Experience, as it is understood and used in the acquisition of expertise, has a
particular definition that should be clarified. As it is described in this model,
experience is not the mere passage of time or longevity; it is the refinement of
preconceived notions and theory by encountering many actual practical situations that
add nuances or shades of differences to theory (p. 407).
EVALUATION OF ANTICOAGULATION CLINIC 12
The processes by which nurses make a clinical assessment out of the available data
are not fully described by any single theory. Benner and Tanner (1987) stated, “Neither
information-processing nor statistical-decision theories are particularly useful in describing
how an expert clinician zeros in on the right region for assessment, selects what is relevant
from the vast field of clinical data available, or recognizes changing relevance as the
situation unfolds” (p. 31).
Thompson (1999) provides a comparative analysis of various clinical decision-
making theories. In his review, Thompson describes the Information Processing Model and
its stages of data analysis leading to a diagnosis. He classifies this model as the Systematic-
Positivist Stance on Decision Making, and links it with a structured decision modeling tool,
or decision tree, that helps nurses reach decisions based on calculated probabilities (p. 1224).
In discussing the rational for accepting an intuitive-humanist model for nurse decision-
making, Thompson states, “The basic thrust of all intuitive-humanist models is that intuitive
judgment distinguishes the expert from the novice, with the expert no longer relying on
analytical principles to connect their understanding of the situation to appropriate action” (p.
1224).
The nurse‟s decision-making process therefore results from a blend of scientific
knowledge with an experiential wisdom. That wisdom is not a magical or unfounded notion
without basis in fact. Within the nurse‟s decisions, there is a component of anecdotal
findings blended with evidence-based practice that takes into account numerous clinical
factors.
Kim (1983) wrote, “Nursing practice encompasses both the scientific problem-
solving orientation and the human-practice orientation. Nurses are not only dealing with and
EVALUATION OF ANTICOAGULATION CLINIC 13
seeking solutions for clients‟ health problems but are also concerned about how to help
clients in their “living with” certain health-related situations” (p. 2). The nurse‟s attention to
both aspects of health concerns may influence how the nurse manages a clinical situation in
ways that may appear unique to the individual patient. Nevertheless, there may be patterns to
some of these decisions that could become apparent when examining these issues from a
broader perspective.
In a study of nurses‟ views of using computerized decision support software to
provide triage advice, O‟Cathain, Sampson, Munro, Thomas, and Nicholl (2004) observed
that nurses found the software to be a “safety net” and “provider of consistency” on which
they relied more upon when they did not have relevant clinical knowledge (p. 280). The
nurses in this study also felt that the software was by no means sufficient, and that there were
circumstances where “the nurse interpreted the software recommendation in the light of
information the software could not process” (p. 283). This would support the theory of a
clinical decision-making process guiding the nurse in an assessment of the applicability of a
decision tree recommendation. Benner‟s expert nurse judgment model would apply in these
circumstances. With the novice nurse, Benner and Tanner raise the following concerns:
Beginners who, because they have no experience with the situations in which they are
expected to perform, must depend on rules to guide their actions. Following rules,
however, has limits. No rule can tell novices which tasks are most relevant in real
situations nor when to make exceptions (Benner & Tanner, 1987, p. 28).
In situations where a decision support tool is being used to assist nurses, especially
when there are varying levels of nurse experience, it is critical that the tool be as fully
developed as possible to prevent advising a nurse to go through with a potentially unsafe
action. In the case of the novice nurse, the inability to recognize an exception to the rules
could result in adverse outcomes. Although a decision support tool may be considered a
EVALUATION OF ANTICOAGULATION CLINIC 14
back-up or a “safety net” for the expert nurse, the tool has much more significant influence to
the less experienced clinician.
Organizational setting. The practice where this project is conducted is a large,
multi-specialty group that serves the North Shore of Massachusetts. Within the practice are 6
primary care physicians, 7 primary care nurse practitioners, 3 primary care physician
assistants, 3 cardiologists, 1 pulmonologist, 2 nephrologists, 1 hematologist/oncologist, and 2
gastroenterologists.
Patients may be enrolled in the anticoagulation clinic for a variety of medical
conditions. Some of the potential indications for therapy include:
Atrial Fibrillation/Flutter
Prosthetic Heart Valves
Deep Vein Thrombosis or Pulmonary Embolism
Post-op high-risk procedure for venous thromboembolism
Treatment of hypercoagulable conditions
Left Ventricular Dysfunction
(Hirsh, Fuster, Ansell, & Halperin, 2003, & Lip, 2007)
The anticoagulation clinic for the group practice is staffed by 4 registered nurses who
manage all of the patients in the group who receive anticoagulant therapy. The number of
patients followed by the clinic at any point in time typically averages 350 people. The RNs
in the clinic rotate through staffing the sessions leaving 1 RN in clinic while the others meet
the other nursing needs of the practice. Anticoagulation clinic sessions are 4 hours each,
open every weekday morning, with an additional afternoon session on Thursdays. In an
average clinic session, the nurse will manage between 15 and 30 patients. A majority of
patients managed by the clinic are treated with face-to-face visits with the nurse, and a
portion of home-bound patients are treated over the phone. The face-to-face patients are
tested with a point-of-care INR device, and the home-bound patients are tested by a home-
EVALUATION OF ANTICOAGULATION CLINIC 15
draw with either a visiting nurse service or the hospital lab. To increase the speed and
efficiency of the clinic, a medical assistant staffs the clinic with the RN to retrieve patients
from the waiting room, collect vital signs, and perform the INR testing.
In the nurse-managed anticoagulation protocol studied in this project, a treatment
model emerged over 10 years based upon the needs of the patients and providers. Initial
guidelines were based upon an original study published in the American Journal of Health-
System Pharmacy in 1966, and these were adapted to meet the unique circumstances of the
individual practice. Various quality improvement and systems changes were implemented
over the years following feedback from patients, nurses, physicians, and credentialing
organizations. The model that was in use by the practice at the start of this project had
emerged by an organic process of change, without a formalized analysis of its efficacy or
safety.
The anticoagulation protocol being evaluated was a developed tool that guided the
nurses in monitoring the INR and adjusting warfarin dosing appropriately. Depending on the
INR target-range, the nurse would follow one of two protocols: Protocol 1 for Goal INR 2-3
or Protocol 2 for Goal INR 2.5-3.5 (see Appendix E). The protocols listed ranges of INR
results and provided guidance on when to adjust the dosing, by how much the dosing should
be adjusted, when to seek assistance, and when to repeat testing. The recommended dose
adjustments were determined by a dosing formula previously developed by the British
Society for Haematology in 1989 which was adapted for the clinic (see Appendix E). The
nurse had a limited amount of flexibility surrounding dose adjustments provided within the
protocols to allow for individualized tailoring of care. Although the charting of patient
encounters was done within an electronic medical record, there was no computer based
EVALUATION OF ANTICOAGULATION CLINIC 16
decision-making support for the protocol. The clinic algorithm design was similar to two-
step protocols found within the literature (e.g. Kim et al., 2009).
The nurses had variable years of experience as nurses, and different educational
backgrounds (see Table 1). Additionally, the nurses had varying levels of experience with
anticoagulation monitoring, and one nurse provided similar services at a separate primary
care practice in the area. All of the nurses received their additional education, training, and
experience in anticoagulation management through employment at the practice. Since
anticoagulation monitoring is not an area of focus for most nursing programs, the nurses
depended upon members in the clinical site for advice and support in assimilating this new
role.
Problem
As the literature on nurse decision-making suggests, the nurses in the clinic appeared
use the anticoagulation protocol as a resource, but relied upon their knowledge base for an
ultimate decision on dosing and follow-up recommendations. The protocol was used as a
tool, but had significant limitations when applied to patients with various clinical issues. The
nurses appeared to make clinical assessments beyond those dictated by the protocol, and
responded to those assessments according to their clinical judgment or intuition. Their
clinical decision-making process was not well understood, and the outcomes associated with
their actions had not been formally evaluated. Although variations from protocol are made to
improve safety and create better outcomes, the validity of these variations was not known.
Some practice behaviors employed by the nurses anecdotally appeared to be clinically sound;
nevertheless, the variations in practice behaviors had not been described nor formally
assessed.
EVALUATION OF ANTICOAGULATION CLINIC 17
Over the years, the nurses had raised many questions relating to the structure of the
program and how this protocol compared to other nurse-managed clinics. Specific concerns
related to scope-of-practice regulations, patient safety, and clinic efficiency. These questions
had been raised both informally, and at regularly scheduled team meetings. The
anticoagulation clinic did not engage in any regular quality assessment procedure. There was
no tracking of outcome measures or adverse events. The clinic protocols had not been
revised since January, 2003. The frequency of nurses in the clinic appropriately following
the anticoagulation clinic protocol was not known, as it had never been quantified, nor had
the frequency of prescriber involvement been assessed.
Intended Improvement
The purpose of this project was to establish a baseline quantitative assessment of the
safety and efficiency of the clinic‟s ability to meet patients‟ INR goals and identify
vulnerabilities and deficiencies within the system. Additionally, the project assessed practice
behaviors that the clinic‟s nurses employed while working with the protocol and identified
potentially beneficial or detrimental decision-making patterns in anticoagulation care. Using
these data, this project recommended evidence-based improvements to increase the safety
and effectiveness of the anticoagulation clinic through the identification of the barriers to
safe, reliable, and efficient clinic workflow, and assessment of the nurses‟ decision-making
process in anticoagulation care.
This process was triggered by the identification of systems-deficiencies by the nurses
in the clinic and the clinic‟s Medical Director. The concerns regarding patient safety and
inefficient practices that were reported by the nurses prompted the Medical Director to
commission this program evaluation project.
EVALUATION OF ANTICOAGULATION CLINIC 18
Study Questions
In order to evaluate this operating model of a nurse-managed anticoagulation
protocol, this project addressed the following questions related to the protocol:
1. What are the clinical situations in which a nurse may find the anticoagulation
protocol to be inadequate, under-developed, or inappropriate for which she must seek
the guidance of a prescribing provider?
2. Where are the opportunities within the existing anticoagulation protocol to improve
safety, decrease nurse-workload, decrease the need for physician-involvement, and
decrease patient-visit-burden?
Specific Aims:
1. To identify aspects of the existing anticoagulation protocol that need improvement or
revision.
2. To explore the decision-making process employed by nurses in the management of
anticoagulation.
3. To identify clinical situations that lead to conflicts between the nurses‟ judgment and
protocols.
4. To recommend interventions to improve the nurse-managed anticoagulation protocol.
EVALUATION OF ANTICOAGULATION CLINIC 19
Methods
This project utilized evaluation research methods to provide summative and formative
evaluations of the anticoagulation protocols utilized by the Anticoagulation Clinic. The
overall method for the project was based upon the Center for Disease Control‟s (CDC)
framework for planning and implementing practical program evaluation. This framework
involves the following steps:
Engage stakeholders
Describe the program
Focus the evaluation design
Gather credible evidence
Justify conclusions
Ensure use and share lessons learned (Centers for Disease Control, 2005).
This framework was developed for programs of public health, but can be directly applied to
this clinical setting. It was particularly useful because it involves conducting an assessment
on a whole system rather than just its individual parts. A comprehensive anticoagulation
program is more complex than a dosing calculator, an algorithm, or a charting system alone.
This model allowed for a description of the current program, followed by a process that
identified the key features within this unique program that required further investigation and
the provision of recommendations for change.
Sample
For this project, there were no exclusion criteria. The 4 registered nurses who staff
the clinic were asked to participate in this program evaluation project, and there were no
additional inclusion criteria. This project was a census of staff, and there was no additional
sampling. The clinic‟s nurse practitioner, a doctoral candidate, conducted the formal
program evaluation and provided recommendations for change.
EVALUATION OF ANTICOAGULATION CLINIC 20
Setting
The project took place at the Anticoagulation Clinic in The Medical Group, Inc, a
large, multi-specialty medical practice on the North Shore of Massachusetts that is described
more fully in the background section above. The Anticoagulation Clinic provides
anticoagulation management services for patients who are followed by providers in this
multi-specialty practice. During each of the 4-hour sessions (6 sessions per week), an RN
manages the face-to-face patient encounters in which patients are tested with a point-of-care
INR device. The RN provides dosing and follow-up instructions to the patients according to
clinic protocols. For questions or concerns with dosing, the clinic nurse seeks the assistance
of the supervising physician or nurse practitioner.
Planning
The evaluation was conducted in several stages. The step of engaging stakeholders
was intrinsically complete before the formal evaluation began. The clinic RNs approached
the supervising physician and nurse practitioner with a request for more decision-making
support in the clinic protocol. The supervising physician charged the nurse practitioner to
conduct a quality improvement project to address the nurses‟ concerns. As the impetus for
this project arose from concerns expressed by the nurses and the supervising physician
during numerous planning meetings, the concept of program revision was fully supported by
these key stakeholders. The anticoagulation program that has been described in this
manuscript, and its operational functions, are provided in detail within the clinic‟s written
protocols and procedures manual (see Appendix E).
The program evaluation was completed through a series of 2 focus group sessions
with a data collection phase between them. Utilizing applied research methods (Kreuger,
EVALUATION OF ANTICOAGULATION CLINIC 21
1994), focus group interviews were conducted with RN clinic providers. This stage of
exploratory research identified key clinical phenomena involved in anticoagulation
management. According to Kreuger (1994) “The focus group interview works because it
taps into human tendencies. Attitudes and perceptions relating to concepts, products,
services, or programs are developed in part by interaction with other people” (p. 10). Due to
the complex interaction of clinical situations with inter-professional dynamics that is seen in
a clinic setting, this property of focus group interviewing proved particularly useful in this
analysis. As Kreuger (1994) stated, “The intent of the focus group is to promote self-
disclosure among participants” (p. 11). As a main goal of this study was to identify issues in
the decision-making process employed by nurses, self-disclosure on the part of the nurses
was vital to the success of this project. The focus group provided a collegial environment in
which the nurses felt comfortable discussing their personal practice behaviors.
Focus group research is uniquely suited for quickly identifying qualitative similarities
and differences among people. Focus groups also provide an efficient means for
determining the language people use when thinking and talking about specific issues
and objects, and for suggesting a range of hypotheses about the topic of interest.
Focus groups may be useful at virtually any point in a research program, but they are
particularly useful for exploratory research when rather little is known about the
phenomenon of interest. As a result, focus groups tend to be used very early in
research projects and are often followed by other types of research that provide more
quantifiable data from larger groups of respondents (Stewart, Shamdasani, & Rook,
2009, p. 590).
Data from the focus groups were incorporated into a clinic audit tool which was used
to assess adherence to protocol, reasons for deviation from protocol, and prescriber
involvement. The clinical audit tool contained key measures of quality in anticoagulation
management including time in therapeutic range, adverse events, and frequency of follow-up.
The audit tool was used to collect data on the significant clinical phenomena of interest as
EVALUATION OF ANTICOAGULATION CLINIC 22
derived from the focus group, and was designed to detect other cases of clinical conflict that
were not pre-identified by the focus group sessions.
The data from the clinical audit were analyzed and compiled. The analysis compared
the predicted clinical management process as described by the nurses in the first focus group
with the actual functioning of the clinic. The goal of this stage of analysis was to apply
quantitative data of actual clinic operation behaviors to verify or refute the nurses‟
hypotheses relating to their practice styles, and possibly uncover unexpected themes in
management issues. The audit also provided outcomes data associated with various clinical
practices, thus providing an assessment of the effectiveness of various clinical management
strategies.
The clinical decision-making strategies in cases detected by the audit tool that were
not self-explanatory or pre-described in the first focus group session were cycled into another
round of focus group analysis for further interpretation and for hypothesis/change-
recommendation development. Specific cases of interest were pulled for a chart review with
the focus group.
Focus groups have also been proven useful following analyses of large-scale,
quantitative surveys. In this use, the focus group facilitates interpretation of
quantitative results and adds depth to the responses obtained in the more structured
survey. Focus groups also have a place as a confirmatory method that may be used for
testing hypotheses. This application may arise when the researcher has strong
reasons to believe that a hypothesis is correct, and where disconfirmation by even a
small group would tend to result in rejection of the hypothesis (Stewart, Shamdasani,
& Rook, 2009, p. 590).
The justification of conclusions stage of the project began with analyzing the findings
of this data collection process, and comparing the findings to the existing evidence-based
literature. Through this process, recommendations for change and adaptation of the protocols
were made. Recommendations were made to include those clinical issues that were
EVALUATION OF ANTICOAGULATION CLINIC 23
appropriately managed as demonstrated by positive clinical outcomes and supporting
evidence for practice behavior in the literature. Clinical practices that were not evidence-
based and were not supported by positive outcomes were identified, and educational
remediation strategies were recommended. Clinical practices that were not evidence-based
but resulted in positive outcomes were identified as areas for future research. These stages of
data interpretation with comparison to the literature, and revision of protocols satisfied the
final steps in the CDC framework for justifying conclusions and ensuring use/sharing lessons
learned.
A graduate student assisted in this program evaluation project. This student is one of
the nurses in the clinic, and she was particularly interested and involved in this process of
program improvement. The student was responsible for assisting in the collection of
quantitative data using the audit tool. Her work was reviewed for accuracy by the primary
investigator.
Focus groups. The focus groups were conducted by the primary investigator (PI)
who served as the moderator of the discussion. Prior to involvement in the sessions, all
participants went through the process of informed consent (see Appendix B). The session
was audio taped and transcribed, and field notes were taken by the PI as per standard focus
group methods (Krueger, 1994). The first focus group session was approximately 90 minutes
in duration, and was conducted on site at The Medical Group. The discussions were guided
by a standard focus group interview guide that had an agenda of uncovering clinical issues
experienced by the nurses in this setting (see Appendix D). Based on typical focus group
guidelines, the tool contained 10 open-ended questions related to the topic of interest
(Stewart, Shamdasani, & Rook, 2009).
EVALUATION OF ANTICOAGULATION CLINIC 24
The qualitative description form of formal content analysis (Sandelowski, 2000) was
employed to identify the key clinical concepts described by participants. According to
Kreuger (1994, p. 153), “Ideally, the moderator or assistant moderator should also do the
analysis. These individuals have had firsthand exposure to each of the discussions, observed
the interactions of all participants, and likely have had the most intensive exposure to the
problem at hand”. As such, the PI was responsible for this stage of analysis.
Once compiled, the results of the content analysis were presented back to the focus
group for assessment of reliability of transcription and validity of analysis. This step was
supported by focus group research methodology and the principle that “analysis is improved
with feedback” (Kreuger, 1994, p.137).
Following a formal clinic audit relating to the topics of interest identified in the first
focus group, a second focus group was conducted. During the second focus group session,
the results of the clinic audit along with highlighted cases for review and additional
observations made by the PI during the audit were presented back to the nurses. The nurses
were asked to provide feedback related to the findings of the audit process and to verify or
refute the assessments made by the auditor.
Audit tool development. The data obtained from the first focus group were
transformed into measurable factors related to these key clinical issues, and these factors
were incorporated into a clinical audit tool. The audit tool was divided into two distinct
sections (see Appendix G). The first was designed to be completed by the RNs at the point
of care with each clinic visit. This tool was designed to capture the frequency of the
described clinical issues. As such, the tool utilized key items from each of the themes
identified during the focus groups. The RN portion of the audit tool contained 31 distinct
EVALUATION OF ANTICOAGULATION CLINIC 25
decision-making factors and a comments section, all of which allowed the nurses to identify
clinical factors that affected their dosing recommendations at the time of the visit. The titles
of these items were created using the terminology used by the nurses, as the goal was to
capture the occurrence of various decision-making factors employed by the nurses. The
nurses were asked to identify on the audit tool which decision-making processes they used
that affected their warfarin regulation decisions immediately at the time of the visit.
The second section of the audit tool was completed by the PI and was designed to
capture the frequency of nurses deviating from clinic protocols for their stated rationales and
for any other reasons. The comprehensive tool was designed to identify the clinical
outcomes associated with various practice behaviors, specifically those which involved
variations from protocol. The PI portion of the audit tool contained 24 different data points
related to the patient presentation, dosing instructions, and patient outcomes. The PI audit
was completed after the patients‟ subsequent follow-up visits to the clinic in order to allow
for observation of dose response and any adverse outcomes.
Best practice outcomes measures previously defined by Fitzmaurice, Kesteven, Gee,
Murray, & McManus (2002) include a process of data collection that tracks the occurrences
of adverse events associated with anticoagulation therapy. For the purposes of this study,
generally accepted definitions of major adverse events were used related to bleeding and
thromboembolic events. Major bleeding includes intracerebral bleed, bleeding that
necessitates suspension or reversal of therapy, bleeding necessitates administration of blood
products, bleeding that leads to death (Ansell et al., 2001). Thromboembolic events include
thrombotic strokes, pulmonary embolism (PE), systemic embolism, and deep vein
thrombosis (DVT).
EVALUATION OF ANTICOAGULATION CLINIC 26
Analysis
Focus group analysis. The tape-recorded 90 minute focus group session was
transcribed for analysis. Data from the first nursing focus group were analyzed using
qualitative description, as described by Sandelowski (2000). Qualitative description was
selected because it is less interpretive than grounded theory and phenomenology, but more
interpretive than quantitative description (White & Ferszt, 2009). The moderator, clinic
nurse/MSN student, and PhD-prepared expert qualitative researcher all independently
reviewed the transcription of the focus group session to gain a general sense of the ideas and
themes reviewed in the discussion. On subsequent reads, the transcript was coded into
meaning units that consisted of words and phrases taken directly from the text. From these
meaning units, codebooks were created by the researchers. The codes were collapsed into
categories of higher meaning, and general descriptions of the categories were created.
After the research team members created their individual codebooks, the results were
shared as a team and reviewed for validity. The researchers found a high level of agreement
in the codes with very similar category descriptions. Disagreements in coding were rare, and
these cases were discussed until consensus was reached. Categories of similar content were
collapsed and refined until consensus was reached among the researchers. The various
codebooks at different stages provided an audit trail for the analysis.
The codes were arranged into categories of similar rationales for actions. Each of the
finalized categories represented situations where the nurses identified deficiencies in the
current operations of the anticoagulation clinic. Descriptive summaries of the categories
were written, and supporting participant quotes were incorporated.
EVALUATION OF ANTICOAGULATION CLINIC 27
Clinic audit analysis. The RN and PI portions of the audit were coded and merged
by individual visits, identified by both patient medical record number and visit date, into an
SPSS statistical software file for analysis. The use of codebooks assured consistency of
documentation. Each of the decision-making behaviors was a dichotomous variable with a
positive response indicating that the particular element played a role in the decision-making
process. Extensive data review and data cleaning was completed with the assistance of a
PhD-prepared statistician.
Descriptive statistics and crosstabs statistical analyses were utilized to interpret the
data. Continuous data were assessed using means and standard deviations. Categorical
variables were assessed using frequencies and Chi-square testing to determine statistical
significance. By monitoring the frequency of the clinical factors identified in the focus group
and the nurses‟ clinical actions in response to these situations, the tool allowed for
identification of variability in practice styles and uncovered additional clinical decision-
making factors that were not previously understood or identified. The audit tool was used to
track program performance and collect data on clinical outcomes which helped to support or
refute various clinical practice behaviors. After analysis, the results were then described and
presented in narrative form, tables and graphics.
Throughout the clinic audit process, the PI maintained a journal of observations that
added to the analysis of the data and contributed to the scope and depth of understanding of
the clinic practice behaviors. These significant observations from the journal were included
as findings in the project.
EVALUATION OF ANTICOAGULATION CLINIC 28
Second focus group analysis. The tape-recorded 60 minute focus group session was
transcribed for analysis in the same manner as the first focus group session. Utilizing the
same qualitative description methods used for analysis of the first focus group session, the
moderator (PI) and the PhD-prepared qualitative researcher analyzed the transcript. The
transcribed focus group session was assessed for statements that supported or contradicted
the findings of the audit. The investigators also analyzed the data looking for new clinical
management issues that were not previously identified in the preceding stages of the
evaluation process. These clinical management issues were collapsed into categories of
higher meaning, and the investigators provided descriptive summaries of the follow-up focus
group session.
Ethical Issues
Evaluation of the clinic practices involved comprehensive observation of the nurses
within the clinic. Prior to the initiation of this program evaluation, the project proposal was
submitted to and reviewed by the Simmons College Institutional Review Board (IRB).
Although the project was determined not to be human subjects research but rather
performance improvement, all ethical protections of participants were maintained.
The nurses were asked to divulge their practice behaviors as openly as possible. The
sharing of information regarding performance of job responsibilities opened the nurses to
criticism of their work. The nurses were informed of their potential vulnerability relating to
participation of this project, and they each went through a process of informed consent before
participating in the focus group sessions.
All abstracts from the transcripts of their conversations have been kept anonymous to
protect their privacy. The specific patient care-related cases of clinical concern were
EVALUATION OF ANTICOAGULATION CLINIC 29
addressed in a confidential manner to limit any job security or medical-legal liability
concerns. The nurses were encouraged to report any concerns with the process to either the
primary investigator, their supervisors, or to the Program Director at Simmons College.
Results
The results of the first focus group session addressed the first program evaluation
question: What are the clinical situations in which a nurse may find the anticoagulation
protocol to be inadequate, under-developed, or inappropriate for which she must seek the
guidance of a prescribing provider?
Specific aims of Q1:
1. To identify aspects of the existing anticoagulation protocol that need improvement or
revision.
2. To explore the decision-making process employed by nurses in the management of
anticoagulation.
3. To identify clinical situations that lead to conflicts between the nurses‟ judgment and
protocols.
Outcomes of Focus Group
All 4 of the RNs involved in the clinic participated in the first focus group session.
The demographics of the sample are described in Table 1. The group discussed clinical
issues relating to the existing protocol that was last revised in 2002. This protocol was the
practice standard to which the nurses were held accountable when practicing in the
anticoagulation clinic. The group identified clinical decision-making factors that affected
their use of the protocol‟s dosing recommendations. The session was analyzed using formal
content analysis methods. From the content analysis, the following categories were
identified as the major topics of interest relating to the research questions and each will be
described in more depth (See Figure 1 and Table 2):
EVALUATION OF ANTICOAGULATION CLINIC 30
Medication Interactions
New to Warfarin/Suspension of therapy
Trending/History
Dosing Calculator Ineffective
High-Risk/Concerning Factors
Patient Factors and Extraneous Factors
Group Standard
Medication interactions. The nurses identified a lack of guidance within the
protocols in relation to how they should respond to potential interactions between warfarin
and other medications. Specific medications that were identified as particularly problematic
for which the nurses desired additional guidance included Amidoarone, Antibiotics,
Prednisone, Chemotherapeutics, and Blood Products.
The nurses reported a tendency to decrease the dose of warfarin preemptively for
patients starting on amiodarone. “Some of the doctors will cut, let‟s use amiodarone, they‟ll
cut the dose in half, others won‟t cut it that much, they‟ll cut it by maybe 25%. So, kinda
there‟s nothing set as to what to do” (D).
For all concerning medications, the nurses reported following up with the patient
sooner than recommended by the protocol. “Monitoring on antibiotics… you‟re gonna check
them weekly”(B). The nurses reported that they did not make any preemptive dose
adjustments for patients on any medication other than amiodarone, barring prior trending and
history as will be discussed below.
New to wafarin/suspension of therapy. The nurses identified that there is no acute
protocol for patients initiating therapy, or for patients suspending therapy. The nurses
EVALUATION OF ANTICOAGULATION CLINIC 31
reported that the protocol was not effective for patients naïve to warfarin, and only served as
guidance for patients who have been chronically receiving therapy. A similar concern was
raised for patients in the peri-operative period. The nurses felt that they would see the
patients back more frequently following a surgery once the warfarin was resumed.
The nurses identified a lack of guidance pertaining to the management of patients
receiving a low molecular weight heparin, specifically Lovenox, as a bridge therapy.
Trending/history. The nurses described using their assessment of a patient‟s
previous INR values as an indication for adjustment. There were several specific themes
within this category that described their assessment process. One concept frequently
described was self-designated by the nurses as “trending.” Trending was described as a
notable pattern of increasing or decreasing INR values over time. Based upon a patient‟s
values trending upwards or downwards, the nurses described straying from the dose
recommendations and time-to-follow-up provided by the protocol. Nurses described making
increases and decreases in the warfarin dose and following up sooner when the protocol
would make no dose change recommendation.
Another patient history factor that was identified as a source of clinical conflict
related to a patient being “sensitive” or having a labile INR. The nurses reported that a
history of a fluctuating INR or a dramatic response to a small change in weekly dose of
warfarin would cause the nurses to either avoid making a change in warfarin dose as
recommended by the protocol, or making a less substantial dose change than recommended
by the protocol. In all cases, the nurses reported following up more frequently with the
patients.
EVALUATION OF ANTICOAGULATION CLINIC 32
When assessing an out-of-range INR value, the nurses described looking at a patient‟s
history for variances, and if there is no clearly identified reason for the change in INR, they
reported being unclear on how to respond. The nurses reported increasing the frequency of
follow-up and making variable dose adjustments depending on the patient‟s history.
For a patient being started on a specific treatment or medication that was used in the
past on that patient, the nurses reported looking to the patient‟s previous response to that
treatment or therapy. How a patient responded to therapy in the past reportedly influenced
how the nurses would adjust and monitor therapy.
Dosing calculator ineffective. The nurses identified situations where the dosing
calculator would make miscalculation on a percentage change, and therefore failed to provide
them sufficient guidance. One issue that was identified as particularly problematic related to
patients in whom a dose of warfarin was held. Plugging the hold into the dosing resulted in
the dosing calculation being made off of a lower weekly warfarin dose. Also, a subsequent
INR within therapeutic range after a hold would not be identified by the dosing protocol.
The protocol would not assess the therapeutic INR as unstable, and would recommend a
longer return-to-clinic timeframe. The nurses also felt that holding a dose of warfarin made
the anticoagulation management decisions more complicated, and they would prefer to have
more limitations on situations that prompt holding therapy, preferring a decreased dose over
a hold.
Another situation that was identified as causing a miscalculation by the protocol was
having a follow-up appointing any sooner than 1 week from the last appointment. The less
than 1 week follow-up caused the calculator to include warfarin doses that had not yet been
administered to the patient.
EVALUATION OF ANTICOAGULATION CLINIC 33
High-risk/concerning factors. The nurses identified many considerations that
heighten their concern for the patient and cause them to vary from usual practice behaviors.
One such situation is a patient‟s risk for bleeding based upon certain conditions or a history
of bleeding. A similar concern related to a patient‟s risk of falling. The nurses reported
making dose adjustments to keep INRs within a lower therapeutic range and following
patients more frequently.
Situations that would cause the nurses to attempt to keep INRs within a higher
therapeutic range include a patient‟s risk of thromboembolism, specifically stroke, and a
history of a prior stroke. The nurses reported similar concerns for maintaining an INR in a
higher therapeutic range for patients anticipating a cardioversion in the near future. For these
situations, the nurses reported occasionally increasing warfarin doses more than
recommended by the protocol, and following-up more frequently with the patients.
The nurses reported varying comfort levels with following the protocol with patients
who have supratherapeutic INR values. Some of the nurses reported seeking assistance from
a provider with higher INR values, even though the protocol permitted adjustment in therapy
by the nurse alone.
The nurses reported a lack of understanding of the significance of certain clinical
findings and identified a need for further education. The nurses reported feeling unprepared
to assess and respond to abnormal lab values and vital signs observed during clinic. They
were unclear if and how an abnormal vital sign or lab affects a patient‟s warfarin therapy.
Patient factors and extraneous factors. Numerous variables were identified that
affect patients‟ INR values, the ability of the nurses to obtain an INR, and the ability of the
nurse to modify a warfarin dose. One issue related to patient reluctance or willingness to
EVALUATION OF ANTICOAGULATION CLINIC 34
follow recommendations. Reportedly some patients refuse to follow-up within the
recommended timeframe; some patients reportedly prefer to be seen soon, and some longer
than recommended. The nurses reported negotiating with patients over the recommendations
Weekends reportedly created scheduling conflicts for the nurses managing warfarin
dosing for patients who were being seen more frequently. The nurses reported having to
make decisions to see patients a few days sooner or a few days longer than they would like
because of the clinic‟s being closed over the weekend. Similar concerns were raised about
office holidays. Patients who had travel plans reportedly caused the nurses to make similar
sooner-or-later decisions, and also to consider having the INR tested at another location
while away.
When patients had missed doses of warfarin, the nurses reported having to make a
decision about how to respond to the subsequent INR value. The nurses reported looking at
history and trending factors to help in these decisions. Dietary changes and variable alcohol
use was identified as a troublesome issue for warfarin management. The nurses reported
providing the patients with variable recommendations and instructions relating to these
issues.
Identified situations that limit the nurses‟ ability to adjust the warfarin dose included
limited pill strengths on-hand, patients with pre-filled med packets that cannot be changed
immediately by the pharmacy or care provider, and patients who already took a dose of
warfarin on the day of testing. The nurses reported that these situations added to the
complexity of decision-making, and lead to numerous variations to practice patterns.
EVALUATION OF ANTICOAGULATION CLINIC 35
Patients known to be self-adjusting their anticoagulation therapy either through
dietary changes or dose changes were identified as being problematic. Suspicion of self-
adjustment reportedly caused the nurses to question the recommendations by the protocol.
Group standard. Throughout the conversation, the nurses reported many situations
where they were not aware of the instructions provided in the existing anticoagulation
protocol. Rather than following the protocol, the nurses described an informal group
standard which guided their regulation decisions. The nurses all identified knowing how the
others tend to regulate warfarin, and that the behaviors of others influenced their actions.
One such situation involved patients who were near their INR goal. For patients who
were out of range by a “small amount” (seemingly less than or equal to 0.2 out of range), the
nurses reported having a separate acceptable INR range for which they did not adjust the
dosing as recommended by the protocol. Although trending and high-risk/concerning factors
reportedly contributed to this decision, the nurses reported a tendency to accept a wider range
of INR values as being within target range.
Summary of focus group findings. The focus group data findings revealed
numerous reported clinical practice behaviors that resulted from the nurses‟ decision-making
process related to warfarin therapy. The nurses identified numerous perceived deficiencies in
the operating protocol of the clinic. These perceptions needed to be further described,
quantified, verified, and validated through additional data collection. Various practice
behaviors described by the nurses required comparison to the existing evidence in the
literature. Revisions to the protocol at this stage of evaluation would not have been
appropriate because these findings were only the perceived actions of the nurses, and not
verified practice behaviors. Additional knowledge relating to the actual practice behaviors
EVALUATION OF ANTICOAGULATION CLINIC 36
compared to the perceived issues was critical to the process of creating a protocol that is
more comprehensive and better serves the nursing management process.
Methodological considerations. The credibility of the study was assured in several
ways throughout the evaluation process. The interview guide was developed through review
of the literature on anticoagulation management and tailored to the practice setting by the PI
who is the resource provider for the clinic, who is consequently intimately aware of the
clinic‟s operations. Frequently during the analysis of the data, the researchers returned to the
transcript for confirmation of the interpretations. The code books created by the researchers
provided an audit trail for the analysis.
One of the members of the nursing team who participated in the focus group is also
an MSN student. This member was a member of the research team and was able to provide a
second peer evaluator audit. As Sandelowski (1986) stated, “The truth value of a qualitative
investigation generally resides in the discovery of human phenomena or experiences as they
are lived and perceived by subjects, rather than in the verification of a priori conceptions of
those experiences” (p 30). The nurse‟s verification of code meanings was of immeasurable
value in assuring validity, and her participation served as a member check. Beyond the MSN
student, an additional audit was done by a doctorally-prepared qualitative researcher in
nursing. Using investigator triangulation (Cohen & Crabtree, 2008), the codes were cross-
verified by multiple researchers. The ultimate results were reviewed with all the participants
for a final member check (Cohen & Crabtree, 2008). As all of the nurses employed by the
clinic actively participated in the focus group session, the data have additional power and
meaning.
EVALUATION OF ANTICOAGULATION CLINIC 37
It may have been beneficial to supplement the focus group data with individual
interviews. Such a step may have been beneficial in revealing additional topics that the
nurses were not comfortable discussing in a group setting. However, the nurses informally
reported that they enjoyed discussing these issues as a group, and were excited to compare
and contrast practice-style variations. The extent of nurse-reluctance to share information
related to decision-making remains unknown, and could be an area for future investigation.
Outcomes of Practice Audit
The outcomes of the practice audit provided additional depth from the focus group to
answer the first program evaluation question: What are the clinical situations in which a
nurse may find the anticoagulation protocol to be inadequate, under-developed, or
inappropriate for which she must seek the guidance of a prescribing provider? Additionally,
the audit allowed for preliminary answers to the second evaluation question: first program
evaluation question: Where are the opportunities within the existing anticoagulation protocol
to improve safety, decrease nurse-workload, decrease the need for physician-involvement,
and decrease patient-visit-burden?
The clinical decision-making factors were incorporated into an RN audit tool with a
supplemental definition of terms (see Appendix F). Following the development of the audit
tools, the RNs completed a month of data collection in the clinic using the RN audit tool. At
each patient visit, the nurses documented their decision-making factors that influenced their
dosing decisions on the audit tool. After the RN data collection phase was complete, the PI
utilized the investigator‟s audit tool to review each of the visits and assess the outcomes
associated with those visits. The data were analyzed using descriptive statistics and
crosstabs.
EVALUATION OF ANTICOAGULATION CLINIC 38
Description of sample. In total, 422 patient visits were assessed. One of the patient
visits was lost due to a charting error, leaving 421 visits for complete analysis. These 421
individual visits were comprised of 256 individual patients. At the 421 visits, 267 (63.4%)
presented with an in-range INR. An additional 58 (13.8%) presented with an INR within 0.2
above or below the goal range. A total of 52 (12.4%) presented with an INR above the
therapeutic goal range, and 102 (24.2%) presented with an INR below the therapeutic goal
range (See Table 3). These data were compared to a retrospective analysis of the preceding
month in order to assess consistency of the month‟s clinic population. For the month
preceding the clinic audit, there were a total of 411 patient visits with 265 (64.5%) presenting
with an INR in-range, and 92 (22.4%) presenting with an INR within 0.2 above or below the
goal range. The consistency seen between the two months of patient visits demonstrates that
the month assessed by the clinic audit was a typical month in terms of patient presentations
(See Table 4).
A total of 8 distinct indications for therapy were listed in the anticoagulation notes.
The predominant indication was for therapy was atrial fibrillation with 70.5% of the visits
having this indication (see Table 5). There were 7 goal ranges identified from the patient
charts despite the fact that our protocol only contains algorithms designed to manage goal
INR ranges of 2.0 to 3.0 and 2.5 to 3.5. A significant majority of the visits (89.3%) had a
goal INR range of 2.0 to 3.0 (see Table 6).
The same dosing instructions were maintained for 276 (65.6%) of the visits. The total
weekly dosing was increased in 87 (20.7%) of the visits, and decreased in 57 (13.5%) of the
visits. For a single clinic visit reviewed during the audit, the prior dosing instructions were
EVALUATION OF ANTICOAGULATION CLINIC 39
not known and could not be determined at the time of the visit. The nurses held doses of
warfarin in 8 (1.9%) of the clinic visits due to supratherapeutic INRs.
During this audit, there were a total of 7 (1.7%) adverse outcomes which resulted in 6
admissions and 1 out-patient management with suspension of therapy. There were 5 cases of
gastrointestinal bleeding, 2 of which occurred with the INR in-range, 1 with an INR below
range, 1 with an INR within 0.2 above range, and 1 with an INR well above goal range.
There was 1 admission for a critically high INR which did not result in transfusion or
bleeding complications. There was 1 case of post-operative bleeding complications during
the resumption of therapy with an INR remaining below therapeutic range. There were no
identified deaths related to therapy. A total of 8 patients (1.9%) were lost to follow-up
related to either relocation to another clinic or failure to return to clinic within the time
constraints of this audit.
The subsequent INR results were within therapeutic range in 258 (61.3%) of the
cases, and within 0.2 out of range in 55 (13.1%) of the cases. The follow-up INR was above
the goal range in 72 (17.1%) of the cases, and below the goal range in 83 (19.7%) of the
cases, when including all cases that fall out of range.
The nurses reported seeking the assistance of a prescribing provider in 7 (1.7%) of the
cases. There were 199 patients with no reported special considerations, and 1 patient with as
many as 7 special considerations (see Table 7).
The nurses‟ dosing instructions remained within protocol-recommended dosing range
91.2% of the time when assessed within the protocol‟s allowance of 3 mg leeway from the
dosing calculator determined dose. As a means of assessing when the nurses made
adjustments that were not captured by simply assessing weekly total dosing instructions, the
EVALUATION OF ANTICOAGULATION CLINIC 40
audit assessed if the nurse maintained the same dosing instructions, increased or decreased
the dose, or held the dose. The INRs were recorded as being subtherapeutic, therapeutic, or
supratherapeutic. Assessment of these parameters allowed for comparison of instructions to
the INR status. Where it is known that the protocol will recommend no change for a
therapeutic INR, increase of dose for a subtherapeutic INR, and decrease of dose or hold for
a supratherapeutic INR, the parameters would assess agreement of nursing instructions to the
protocol in terms of direction of change. The data revealed that of the 267 patients with a
presenting INR in range, the nurses maintained the same dose for 229 (85.8%) of those
patients. In other words, the nurses changed the dose for 14.2% of the patients with a
presenting INR that was within therapeutic range. These cases would be off-protocol dosing.
Of the cases of an in-range INR and the dose was changed, 24 (9%) of the patients were
instructed to increase the dose, and 14 (5.2%) were instructed to decrease the dose.
When assessing cases of the presenting INR being above range, there were 14 cases
(26.9%) where the INR was above range, but the same dose was maintained. There were no
cases where there INR was above range and the dose was increased. When assessing cases
of the presenting INR being below range, there were 33 cases (32.7%) where the same
dosing instructions were maintained. There were 5 cases (4.95%) where the INR was below
range, but the dose was decreased. In total, based on measures of direction of change, there
were 90 cases (21.3%) where the dosing was off-protocol.
When assessing adherence to protocol, the factor of time-to-follow-up was examined.
The recommended time to follow-up of the nursing instructions compared to the protocol
recommendations were in agreement 43.5% of the time for cases where the prescribed target
EVALUATION OF ANTICOAGULATION CLINIC 41
INR range was one of the standard ranges accepted in the clinic. Thus, 56.5% of follow-up
instructions were off-protocol for patients with standard INR ranges.
Medication interactions. The RN portion of the audit tool included fields for 4
concerning medications or classes of medications that were identified by the focus group as
problematic in relation to warfarin therapy dosing. These medications and classes of
medications were amiodarone, antibiotics, chemotherapeutics, and prednisone. In the audit,
the nurses identified 1 patient on amiodarone, 21 on antibiotics, 7 on chemotherapy, and 13
on prednisone. In addition to these pre-identified medication issues, the nurses recorded
additional concerns in the comments section of the audit with the addition of aspirin, Plavix
(clopidogrel), cochicine, phenazopyridine, Actonel (risedronate), Tylenol (acetaminophen),
and omeprazole. Of the 21 antibiotic cases, the next scheduled follow-up visit averaged 8
day in comparison to a traditional average (or group-average) time to follow-up of 17 days.
Out of the 21 patients on antibiotics, 16 (76.2%) returned with a subsequent INR in-range.
For patients on prednisone, the average time to follow-up was 9.5 days and 9 out of the 13
patients (69.2%) returned with a subsequent INR in-range.
Although the nurses had reported a habit of following-up with patients more
frequently rather than preemptively adjusting a dose when medication interactions were
suspected, the auditor noted several cases where preemptive dose adjustments were made for
medications other than just amiodarone. These cases were pulled for review individually
with the responsible nurse, and the finding was confirmed. These cases were highly
individualized and typically occurred in the presence of other decision-making factors which
will be discussed further.
EVALUATION OF ANTICOAGULATION CLINIC 42
New to warfarin/suspension of therapy. In the focus groups, the nurses identified
concern in relation to patients who were initializing therapy for the first time, patients who
were modifying therapy in the peri-operative period, and patients who were being bridged
with Lovenox (enoxaparin). In total, there were 12 (2.9%) cases that were identified as being
new to therapy, 10 (2.4%) cases that were identified as being in the peri-operative period, and
9 (2.1%) cases of patients receiving bridge therapy with Lovenox (enoxaparin). Due to the
small number of cases with these factors identified in the audit, the individual cases were
reviewed for identification of practice patterns. The time-to-follow-up and dosing
recommendations were highly variable for these patients, and no consistent patterns could be
identified.
Trending/history. The nurses identified 23 (5.5%) cases with a recognized pattern
of trending upwards, and 28 (6.7%) cases with a recognized pattern of trending downwards
that influenced their decision on dosing. The nurses identified 41 (9.7%) cases where the
INR results appeared labile, 34 (8.1%) where there was a history of being sensitive to small
dose adjustments, and 36 (8.6%) cases where the prior history and dose response played a
role in modifying the dosing recommendations.
Of the 36 cases where prior dose response guided treatment, 23 (63.9%) resulted in a
follow-up INR being within range, and an additional 6 (16.7%) were within 0.2 of
therapeutic range. Of the 23 cases of trending up, 14 (60.9%) resulted in a follow-up INR
being within range, and an additional 3 (13.0%) were within 0.2 of therapeutic range. There
were 244 (62.6%) of cases where the subsequent INR was in-range when no upward trending
was observed. A Chi-square analysis of the trending-up and in-range values reveals no
statistically significant difference with a p-value of 0.87. Of the 28 cases of trending down,
EVALUATION OF ANTICOAGULATION CLINIC 43
20 (71.4%) resulted in a follow-up INR being within range, and an additional 5 (17.9%) were
within 0.2 of therapeutic range. Here again, there was no statistically significant difference
with a p-value of 0.31; nevertheless there does appear to be a pattern of improved
achievement of goal INR with attention to the parameter of trending down, with achievement
of target INR range in 71.4% of patients with attention to trending versus overall
achievement of INR in 61.3% of patients.
Dosing calculator ineffective. The audit tool assessed situations where the patient
returned to clinic in less than 1 week from the prior visit, when the previous dosing
instructions included a hold. This category had overlap with other categories in the items of
patients being new to warfarin and patients who missed doses of warfarin. In total, there
were 21 (5%) cases of the patient being seen in less than 1 week from the time of the last
visit and 16 (3.8%) that had held a dose within the previous week‟s dosing instructions, with
both of these situations leading to misleading weekly totals for the dosing calculator.
Holding of warfarin doses proved to be particularly problematic for regulation, and only 3
(18.8%) presented in-range after a hold within the week prior, and 6 (37.5%) returned with
an INR in range at their subsequent visit. With Chi-square testing, this difference was
statistically significant with a p-value of 0.035.
High-risk/concerning factors. There were 11 (2.6%) case instances where the nurse
reported that the INR was above her comfort level for regulating on her own. Nurses
recorded certain factors that they believed placed the patient at higher than average risk for
complications related to therapy and subsequently resulted in their alteration of dosing
instructions. These factors included prior bleeding complications, a patient being at high risk
for falling, a history of thromboembolic complications, or a patient being at high risk for
EVALUATION OF ANTICOAGULATION CLINIC 44
thromboembolic complications. There were 11 (2.6%) case instances where heightened
bleeding concerns affected dosing considerations and 28 (6.7%) case instances where
heightened thromboembolic concerns affected dosing considerations. These cases
heightened concern resulted in a shorter time to follow-up, with an average of 12 days to
follow-up.
Patient factors and extraneous factors. The audit tool captured patient preference
factors for dosing or follow-up, patient dietary changes, patient alcohol intake changes,
missed doses of warfarin, fixed pill strength, weekend or holiday interference with return
visits, and patient travel considerations. There were 17 (4.1%) instances where the weekend,
a holiday, or patient travel plans caused variations from the nurses preferred
recommendations. The weekend and holiday issues occurred mostly (84.6%) with an out of
range INR, when the preferred time to follow-up was within several days and could not be
accommodated due to the scheduling issue. Two of the 4 patient travel issues related to
subtherapeutic INRs resulted in longer than desired return to clinic times. The remaining 2
patient travel issues were cases of patients transferring care to a Florida clinic, yet both were
within therapeutic range at the time of visit. There were at total of 13 visits with reported
patient preference modifications. The issues associated with this report were difficult to
interpret as only one of the visits provided documentation of the patient preference, and in
that case it was an issue with restricted days for transportation. Only 3 (23.1%) of these
visits had a presenting INR within range, and there were no identifiable conflicts with the
dosing recommendations for these visits.
No specific pattern of behavior could be identified in relation to how the nurses
responded to these factors. There were various strategies described by the nurses in how they
EVALUATION OF ANTICOAGULATION CLINIC 45
handled dietary and alcohol factors in relation to warfarin. Some reported that the variation
was temporary, and the dosing schedule was maintained with shorter time-to-follow-up.
Some reported that the variation was ongoing and made adjustments in therapy.
There were 18 (4.3%) identified cases where there were significant dietary changes,
11 (2.6%) others with significant changes in alcohol intake, and 12 (2.9%) patients who
reported missing doses of warfarin. The average time to follow-up for cases of dietary
changes was 11.5 days as compared to 17.14 days for those without dietary changes. The
average time to follow-up for cases of alcohol factors was 13.27 days as compared to 16.99
days for those without alcohol factors. The average time to follow-up for cases with missed
doses was 11.83 days as compared to 17.04 days for those without missed doses.
Group standard. The nurses recognized that they were unfamiliar with the protocol
recommendations for change and for follow-up. In the process of completing this audit,
several of the nurses reported that they rarely utilized the dosing calculator to make dosing
adjustments.
The average time to follow-up recommended by the protocol according the two
standard INR goal ranges was 22.7 days, and the average time to follow-up recommended by
the nurses was 17.0 days for patients with these standard INR ranges. Patients with non-
standard INR ranges will be discussed separately. There were 22 occasions where the nurses
recommended longer return-to-clinic times, with the recommendation being an average of
8.9 days longer for these 22 cases as compared to protocol recommendations. A total of 14
(63.6%) of the longer return-to-clinic cases were in relation to INRs within the 0.2 out of
range parameter. In cases where the INR was within 0.2 of the target range and the nurses
recommended a longer time to follow-up than the protocol, the subsequent INRs were within
EVALUATION OF ANTICOAGULATION CLINIC 46
therapeutic range in 8 (57.1%) of the cases. Nurses were far more likely to recommend
(N=203) a shorter return-to-clinic time, with the recommendation being an average of 12.2
days shorter for these cases than the average time to follow-up recommended by the protocol
despite the presenting INR being within range in 137 (67.5%) of the cases. The subsequent
INR was within therapeutic range in 126 (62.1%) of these cases of shorter time to follow-up.
There were 25 cases of the INR being less than or equal to 0.2 out of range where the
nurses did not adjust the dosing, and 33 cases of the INR being less than or equal to 0.2 out
of range where the nurses did adjust the dosing. The Of the 25 cases where the INR was less
than or equal to 0.2 out of range and the nurses did not adjust the dosing, 1 had a listed
rationale of trending up, and 2 had a listed rationale of trending down. Two of those cases
(one being the trending up case) resulted in the INR being within therapeutic range on
subsequent check, and 1 with an INR being within 0.2 out of range. Five of the 25 cases of
INR within 0.2 of goal range, but no adjustment made had a rationale of the INRs being
labile, 3 with a rationale of the INR response being sensitive, 4 of significant dietary changes,
1 of a missed dose. Subsequently, 16 (64%) of the 25 cases returned with an INR in range,
and 3 (12%) returned with an INR within 0.2 out of range. Of the 33 cases where the INR
was within 0.2 out of range where the dose was adjusted, of which 21 (63.6%) resulted in an
in range INR, and an additional 3 (9.1%) were within 0.2 out of range. When looking at the
patients who were within 0.2 out of range, there were 25 cases where the nurses did not
document any additional concerning factors that played into their decision-making. For
those cases, the nurses kept the same dosing for 11 (44%) of the cases. Thus, for those 11
cases there was no documentation of any supporting rationale for not changing the dose as
recommended by protocol.
EVALUATION OF ANTICOAGULATION CLINIC 47
Previously unidentified issues. The process of the practice audit raised numerous
issues that were previously unidentified. These issues were uncovered through discussions
with the nurses, observation of clinic practices, analysis of audit data, and the journaling
process. These insights into clinic operations were helpful in understanding the strengths and
shortcomings of the clinic operations.
The nurses revealed during the audit process that the dosing calculator was not used
on a regular basis. The nurses often adjusted using percentage change as a reference, but did
not enter the data into the dosing calculator. This may partially have been a result of the
calculator being in a separate computer program that was not part of the electronic medical
record (EMR), as the nurses reported being bothered by having to switch to different screens.
Numerous goal ranges other than the protocol standard goal ranges of INR=2-3 and
INR= 2.5-3.5 were identified and did not fall within the clinic dosing protocols. The use of
the clinic‟s dosing calculator for these non-standard INR goal ranges would not be reliable as
the calculator is intended to determine a dose that will target a resultant INR within 20%
above or below the target INR. If the goal range is narrow, the calculator will not
recommend adjustments when the INR is out of range until the 20% threshold is reached.
The protocol did not have any recommendations for time to follow-up for these non-standard
ranges either. As such, the nurses functioned without protocol guidance for all of these non-
standard INR goal range regulations. The appropriateness of these non-standard INR ranges
requires additional investigation as they are not evidence based. It appears that patients were
enrolled into the clinic with these non-standard goal ranges by orders of outside providers,
and their orders had not been revised to be consistent with acceptable clinic protocol targets.
EVALUATION OF ANTICOAGULATION CLINIC 48
There were several indications for therapy provided in the anticoagulation records
that were not clear indications for therapy and these documented indications for therapy may
have been the result of incorrect or incomplete documentation relating to the patients‟
diagnoses. Peripheral vascular disease, stroke, and coronary artery disease are not standard
indications for therapy unless there are additional factors related to these issues.
Additionally, the duration of therapy may be limited to a finite time span for some of the
indications associated with these issues. As such, the appropriateness of ongoing warfarin
therapy for some of the patients in the clinic could not easily be assessed with the existing
level of documentation in the clinic notes.
Patient tracking issues surfaced during this clinic audit. Some patients were found to
be overdue for INR follow-up through the data collection methods involved in the clinic
audit process. The nurses utilized a paper tracking system to assure that patients were being
appropriately monitored. During the data collection period, patients were identified as being
lost to follow-up and these patients would not have otherwise been found by the paper
tracking system.
There was a common theme of incomplete documentation related to rationales for
dosing instructions. The nurses made note of various clinical considerations on the audit tool
that were not reflected in their documentation for the clinic visits in the patient charts. In
terms of outsiders‟ abilities to assess appropriateness of dosing instructions, the lack of
documentation is a significant hindrance. This has implications for practice and patient
safety as well as legal liability. This is particularly an issue in cases where nurses accept
INRs outside of therapeutic range or otherwise adjust warfarin dosing outside of protocol
standards.
EVALUATION OF ANTICOAGULATION CLINIC 49
The nurses identified issue where certain illnesses raised their level of concern in
monitoring the patient. This concern may have been related to possible treatments and
interactions with warfarin, dietary changes related to illness, or other metabolic factors. The
nurses‟ rationale for being concerned with illness states was not clarified.
A variation within the concept of “trending” was another issue identified within the
review process. The idea of trending was used to describe both short-term as well as long-
term fluctuations in INRs. Short-term fluctuations and long-term fluctuations may need to be
addressed differently as they may represent different underlying causes, with the long-term
trends more likely being a more stable situation. A change from a low-normal INR to a high-
normal INR is less concerning in the long-term follow-up as the rate of change may be more
gradual. There was one identified case of a nurse failing to recognize the intended increase
of an INR with a prior dose increase. The INR at the visit was in-range, but the dose was
decreased to the prior dosing schedule due to a perceived trending issue.
There were several outdated features of the protocol that were noted upon close
review. The protocol referenced an EMR system that was no longer in use, and a point-of-
care INR system that was obsolete. The protocol indicated that the medical assistant was
assessing the patient and the patient‟s INR, reviewing the appropriate dose, and consulting
with the nurse or physician, which was not the case.
The protocol advised the RN to be aware of the possible effects of medications and
dietary changes on warfarin dosing, but did not give nurses authority to modify dosing
instructions based on these data. The protocol does allowed for a 3 mg leeway based on
available pill strengths; however, this amount of flexibility could be as much as 75% of the
weekly dose as is the case for the patients on 4 mg/week. This difference of 3 mg could be
EVALUATION OF ANTICOAGULATION CLINIC 50
so significant in relation to the total weekly dose that it could potentially mean dramatically
increasing a dose rather than decreasing a dose, or vice versa. If the only parameter used to
assess dosing on protocol was the total prescribed weekly dose being within 3 mg of
recommended weekly dose, significant deviations from protocol would be missed.
One particularly interesting finding during this audit was a flaw in the protocol
recommendations relating to dosing calculator results and protocol instructions. The dosing
calculator advised no adjustment be made for anything within 0.6 of the 3.0 target, keeping in
line with the adjustments for doses beyond 20% of the target INR. This has the effect of the
calculator aiming to maintain a target range of 2.4 to 3.6 rather than 2.5 to 3.5 as ordered.
Nevertheless, the protocol instructions advised that an adjustment should be made for INRs
of 2.4 or 3.6 for patients with an INR target of 3.0, leaving no guidance for the nurses from
the dosing calculator. This incongruence in the recommendations had not been identified
until this point.
Limitations. The patient visits were assessed using aggregate data. Multiple patients
did have more than one visit during the audit, and they were treated as separate visits for
analysis. Out of the 421 visits that were analyzed, there were 256 unique patients. The
repeat patients may have distinctive individual confounding factors that could have a
disproportionate impact when assessing the clinic population. The repeat patient visits were
treated as separate visits because they each represented a unique dosing challenge for the
nurses based upon their presentation for that day, and often were treated by different nurses
at their repeat visits. The nurses employed different decision-making rationales for these
visits based upon their clinical judgment in regards to the patient history and presenting
factors which included different INRs at the clinic visit.
EVALUATION OF ANTICOAGULATION CLINIC 51
For the RN portion of the audit, the nurses needed to be able to identify factors that
contributed to their dosing recommendations. Subconscious thought processes or failure to
record a factor would result in failure to identify instances of certain decision-making
rationales. Use of the terminology, as captured by the focus group session, that was normally
employed by the nurses allowed for improved identification of the decision-making factors at
the time of the visits, and may have helped to minimize this issue. Where the terms used on
the audit were the natural words that the nurses used to describe their thought processes,
these were more likely to be identified on the audit tool.
The RN portion of the audit was subjective to each nurse. The tool did not assess if
there was an objectively observable factor involved, and solely assessed the nurses‟
perception of those factors being present. This distinction was beneficial in that it allowed
for an understanding of how the nurse responded when she perceived a certain factor being
present, but did not assess how often there was objective evidence for these factors being
present.
As there were 5 additional non-standard goal ranges found in the audit (5% of total
visits), cases with these ranges could not be accurately assessed by the standards of the
existing protocol. The dosing calculator used in the protocol would provide dosing
recommendations for any single goal INR value, but the acceptable range may differ from
the prescribed range as previously discussed; nevertheless, follow-up recommendations did
not exist within the protocol for non-standard goal ranges. This factor decreased the number
of cases that could be compared to the protocol‟s standards from a total of 421 cases to 400
cases.
EVALUATION OF ANTICOAGULATION CLINIC 52
The frequency of many patient factors that affect the nurses‟ decision-making was too
low to allow for statistical analysis of these items. As such, certain items could only be
assessed in terms of individual case analysis. Longer periods of data collection may have
been beneficial to capture additional cases of these less frequent decision-making factors.
Additionally, the evaluation was not a randomized-controlled trial of the impact of the
decision-making factors on patient results. The observational design of this study limits the
strength of the findings.
Outcomes of Second Focus Group
At the completion of the clinic audit, a second focus group session was conducted.
The second focus group session allowed the nurses to review the findings from the clinical
audit so that they may provide informative feedback. All 4 of the clinic RNs participated in
this focus group review of the results from the audit and the observations made by the
auditor. Additionally, the nurses reviewed a total of 5 cases that were identified in the audit
where the auditor could not determine supporting rationales for the off-protocol dosing
advice from the patient charts or from the RN audit tool. The results were analyzed using
qualitative description. The following categories of were identified as major topics of
interest related to the evaluation questions and will be discussed in depth (See Table 8):
Agreement with findings
Documentation hindrances
EMR deficiencies
Routinized patterns of behavior
EVALUATION OF ANTICOAGULATION CLINIC 53
Agreement with findings. The nurses generally agreed with the assessments and the
overall findings of the clinic audit. They did not identify any areas of dissonance of the
findings with their notions of clinic functioning.
In terms of medication interactions, the nurses agreed that they require additional
support in determining appropriate warfarin dosing with specific medication interaction
concerns. When discussing the available drug interaction reference, one of the nurses
reported, “The problem is that it doesn‟t tell you how badly the interaction is and how many
days, and it doesn‟t give you any guidance” (D). The nurses‟ made multiple comments
describing their uncertainty with how to handle certain medication interactions. Their
statements of uncertainty supported the finding of the need for further nursing education in
this realm.
Relating to trending, the nurses recognized the variations on their understandings of
the concept of trending, and the differences between a perceived trend over a long period of
therapy versus a trend over several days. “She went 3.4, 3.2, 2.9, 2.3. So that‟s what I was
looking at. But that‟s over a 2 month time period” (B).
There were many occasions where the nurses identified problems with the dosing
calculator being ineffective, especially in relation to a hold in the previous week. “If you
look at the flow sheet, this is where he was 3.8 and then, yup. Well it‟s deceiving because it
looks like the dose was increased, but it really was just plugging in that hold” (B). The
nurses also recognized some inconsistencies in thought processes relating to the management
of held doses. “And, I‟m just kind of leery. So technically we did increase the dose” (C).
There was significant agreement among the nurses that that the patients‟ reports of
various issues alter their dosing instructions, but that this information is often not captured in
EVALUATION OF ANTICOAGULATION CLINIC 54
the visit note. “Sometimes it depends on the chat that you‟re having with the patient” (A).
“Absolutely. But I even notice myself, I‟ll look back and I‟ll go, „Who the hell did that?!‟
And I‟ll go, oh, I did it! You know, and I would never have done that today, but geez, but
they made me do it then” (B).
The nurses acknowledged their practice of accepting INRs that were close to the
target therapeutic targets but out of range as normal values. “But I think what we are looking
at is the 2.5 to 3.5, and saying, „3.5 is fine,‟ So what is 3.8? That‟s fine. And that‟s where
we‟re seeing it, and that‟s how we have been doing it all along” (A). “And 1.9 doesn‟t get
me too excited because they‟re still pretty close” (A). The nurses agreed with the assessment
that they tend to view the endpoints of the target therapeutic ranges as the actual targets
rather than the target INR which is in the middle of those endpoints. “I have not looked at it
as 2-3 seeing 2.5. I have not” (A). “And that‟s why I can understand accepting ranges, but
it‟s almost like we should just be saying TARGET 3.0. Okay if you are 2.5 to 3.5, but
TARGET is …” (B).
The nurses reported various practices relating to changes in dietary vitamin K intake,
and also discussed their recommendations to the patients relating to this issue. “They‟ll say
oh geez, I want to increase my greens when can I do it? And then, okay you‟re 2.8 today,
now‟s a good time. Or you‟re 3.3, today‟s your day” (B). The nurses also suggested that they
will advise patients to increase dietary intake at times beyond just accommodating patient
preferences. “I will write preference versus instructed in my notes, or I try to…” (B).
A habit of following intuition and feelings rather than adhering to a standard protocol
or methodology was also noted. “Yeah, and looking at this today, this is the other thing is,
even myself, I can look at the same case two different days and do two different things with it
EVALUATION OF ANTICOAGULATION CLINIC 55
Umm, and yeah, today I would say no, I probably would have just left it alone and checked it
again in 3 weeks. So it depends on which way the wind‟s blowing that day on how I do
things sometimes” (B).
There was recognition of the various non-standard goal INR ranges and the
incomplete documentation surrounding indication for therapy and duration of therapy. “Also,
when we have someone on the template, we have no idea who put that target range in there,
when it was changed, or whose whim it was on” (B).
Documentation hindrances. The nurses identified numerous issues that hindered
their abilities to provide adequate documentation. They recognized the need for improved
documentation. “In Coumadin Clinic, that‟s our biggest issue” (A). “It‟s confusing to read
the note. I appreciate us coming in and seeing it” (C).
Part of the rationale for not including certain elements of the decision-making process
was reported to be due to a different concept of what needed to be documented in the note.
“But in all honesty, I don‟t often, and I can‟t even imagine writing that the dose was held last
visit when you‟ve got it right there on the flow sheet. I‟m kind of writing things that aren‟t
apparent from the flow sheet. I assume that you can see that, that it was held” (B). The
nurses also reported a lack of consistency in documentation due to provider preferences for
placement of information within the documentation. “And also have all of the providers on
the same page about where they want us to put the information” (D).
Once the nurses recognized the need for more clear documentation, they had concerns
about the impact of that on their workload. “That‟s gonna take a lot more concentration”
(B). “I‟m overwhelmed sitting here right now because you have no idea how many of those
make sure you click that button, make sure you report the INR, you know what I mean?” (B).
EVALUATION OF ANTICOAGULATION CLINIC 56
The available amount of time to see a patient and document the care was a significant
concern for the nurses. “Again we‟re down to a very very small fraction of the time being
seeing the patient” (A). Being busy with multiple patients was a reported reason for failing
to provide complete documentation. “It‟s like plenty of time when things are going well, and
when you‟ve got 5 people that come in that are way off track and everything‟s happening to
them, and that‟s how you don‟t chart sometimes” (A). One nurse made suggestions to
another on how to slow down the pace of clinic to make things more manageable.
One rationale for not documenting information in the patient charts was the format of
the EMR system. The computer system would print the information entered by the nurses
into the instructions the patient received at the end of the visit. “Unfortunately, if we write a
lot of that into the note now, the patient receives that also. It‟s part of his instructions” (A).
The absence of standardized documentation templates was another identified
hindrance to charting. The nurses felt that addition of a charting template would be a step
towards improved charting. “I‟ve seen examples of different documentation from different
clinics where there‟s areas, you know, different questions that you have to ask to make sure
that you kind of document, like makes you include it in the note” (D).
EMR deficiencies. There were numerous deficiencies within the EMR system that
were identified by the nurses. One particularly troubling issue for the nurses related to how
the system charted dosing instructions at the visit after a hold. Because the system would
compare the current week‟s dosing total to the prior week‟s dosing total, the system would
automatically record that there was a dose increase, even though the total weekly dosing was
lower than the week prior to the hold. The nurses identified that they would have to
manually delete out the text created by the system to clarify the overall dosing changes.
EVALUATION OF ANTICOAGULATION CLINIC 57
The weekly dosing calculator did not automatically update the total weekly dosing
without the nurses clicking a box to recalculate the dose. If the nurse forgot to update the
dosing total, the following visit would be confusing to the nurse reviewing the instructions.
“These are the things that drive us out of our minds. Because even just trying to figure things
out, that day I‟m trying to read it across and I would have been looking at total weekly doses,
and when you realize they don‟t match…” (B).
The nurses felt that the deficiencies of the EMR impaired their abilities to see patients
more efficiently. “[I] think a lot of the problem with me is computer program. Because we
are always having to fix something. Something doesn‟t come out in the flow sheet, something
doesn‟t come out show up. We spend more time babysitting the computer sometimes than we
do with the patient” (A).
Routinized patterns of behavior. There was recognition of engrained patterns of
behavior with patients, nurses, and prescribers relating to warfarin therapy that would require
additional attention. The nurses felt that these routines would be difficult to change.
In relation to the patients, the nurses reported a need to change their expectations
relating to dosing instructions. “I don‟t think patients who have been on it a long time are
going to come back sooner. I don‟t think the compliance will be there” (A). In considering
their own habits, the nurses reported that this would be a process of change, as well. “It‟s
tough to teach an old dog new tricks” (B).
Changing prescriber habits was another issue of concern for the nurses. They
identified variable understandings on the part of prescribers of the established clinic policies.
The nurses felt that prescribers needed additional training in the operations of the clinic and
EVALUATION OF ANTICOAGULATION CLINIC 58
the preferred dosing instructions. They felt that certain providers had expectations of the
clinic and the clinic nurses that were not consistent with the established policies.
Summary of second focus group findings. The second focus group confirmed
many of the findings and observations made during the clinic audit process. The nurses
agreed with the need for various changes to the clinic protocols and the patterns of behavior.
They recognized the need for additional education relating to certain areas of practice that
were found to be problematic in the audit. Factors that contributed to inadequate
documentation were identified, as were some strategies to reduce the impact of these factors.
Additionally, the nurses identified deficiencies within the system that negatively affected
their quality of care.
Discussion and Recommendations for Change
Assessment of the clinic outcomes data with comparison of the focus group items and
the observed patterns of behavior to the existing literature comprehensively addressed the
second program evaluation question: Where are the opportunities within the existing
anticoagulation protocol to improve safety, decrease nurse-workload, decrease the need for
physician-involvement, and decrease patient-visit-burden?
The process of analyzing the findings and looking to the evidence in the literature for
support of recommendations for change further supported the associated aims of the research.
Specific Aims of Q2:
1. To identify aspects of the existing anticoagulation protocol that need improvement or
revision.
2. To explore the decision-making process employed by nurses in the management of
anticoagulation.
3. To identify clinical situations that lead to conflicts between the nurses‟ judgment and
protocols.
4. To recommend interventions to improve the nurse-managed anticoagulation protocol.
EVALUATION OF ANTICOAGULATION CLINIC 59
The concept of nurse decision-making processes superseding a clinic protocol as
identified in the literature was supported in the findings of this program evaluation. The
nurses utilized a process of patient assessment that went beyond what was dictated by the
protocol. This process of assessment caused the nurses to use the protocol as a reference, but
not the deciding factor for patient care. As reported by O‟Cathain et al., “the nurse
interpreted the software recommendation in the light of information the software could not
process” (p. 283).
Overall, the baseline data from the clinic audit revealed that this anticoagulation
clinic had typical therapeutic success rates with a total of 63.4% of patients presenting with
an INR within therapeutic range during the audit when compared to findings of other clinics
in the literature maintaining patients in therapeutic range an average of 66% of the time (van
Walraven, Jennings, Oake, Fergusson, & Forrester, 2006). The adverse events data were in-
line with prior meta-analyses that demonstrate half of adverse events occur while the INR is
within therapeutic range (Oake, Fergusson, Forster, & van Walraven, 2007). In the literature,
frequency of major hemorrhage is approximately 7.7% per patient-year of therapy (Ansell et
al., 2001), which would translate to an expected 1.64 patient events per month in a
population of 264 individual patients, as was the size of this sample. The event rate was
higher (7 patients as compared to a predicted 1.64 patients) in the month studied as compared
to these statistics. Additional months of data collection would be necessary to assess if the
sampled month had typical rates of complications for this clinic. This is certainly an
outcome measure that must be monitored very closely.
The clinic nurses remained within protocol standards for dosing 91.2% of the time
when looking at weekly dosing totals, which is greater than the frequency reported by
EVALUATION OF ANTICOAGULATION CLINIC 60
Shimbukuro and Kramer (2004) of 86.4% of dose instructions being on-protocol. However,
when assessing adherence by measures of direction of change (i.e. absolute instruction of
dose increased, decreased, or maintained the same as determined by the nurse versus the
protocol), the rate of adherence to protocol recommendations was 78.7% (see Table 9). Even
more significantly, the recommended time to follow-up was only in agreement with the
protocol recommendations 43.5% of the time for cases where the prescribed target INR range
was one of the standard ranges accepted in the clinic. It was this significant difference
between protocol instructions and nursing recommendations that demonstrated the need for
systems improvements.
Medication interactions. It has long been recognized that the anticoagulant response
of warfarin is influenced by pharmacokinetic factors of drug interactions that alter absorption
and metabolic clearance of the drug (Hirsh et al., 2003). Although the protocol did recognize
the possible effects of various medications on warfarin dosing, it did not provide the nurses
with the authority to adjust warfarin dosing recommendations based on those potential
interactions. In the initial focus group session, the nurses appropriately identified a need for
preemptive dose adjustments for certain medications as well as a need to follow patients
more closely when there was a concern for medication interactions. As discussed previously,
the nurses followed patients with medication concerns more frequently than recommended
by protocol standards.
Prednisone was identified as a medication of particular concern. Case reports in the
literature have found prednisone to increase INR to varying degrees (Stading, 2006). The
nurses were using sound clinical judgment in monitoring these patients more closely.
EVALUATION OF ANTICOAGULATION CLINIC 61
Although amiodarone was only an issue in a single case during the audit, this is
certainly an example of a medication that requires special attention in a modified
anticoagulation protocol. Amiodarone inhibits the metabolic clearance of both S- and R-
isomers of warfarin and potentiates wafarin anticoagulation, but other medications, such as
omeprazole, only inhibit clearance of R-isomers and potentiate the anticoagulation only
modestly (Hirsh et al., 2003). This distinction in the pharmacologic pathways of various
medication interactions with warfarin is helpful in determining the anticipated strength of
effect of an interaction, and can guide a provider in decisions regarding preemptive dose
changes versus more frequent follow-up.
The benefits of preemptive dose adjustments when initiating medications with a
known effect on warfarin have been demonstrated in numerous studies. As the nurses
reported a practice of not preemptively adjusting warfarin for antibiotics and demonstrated
more frequent follow-up, this area deserved particular attention. Ahmed, Stephens, Kaus,
and Fay (2008) demonstrated that with trimethoprim-sulfamethoxazole and levofloxacin, a
strategy of preemptive dose reduction for the former and no change with short-term follow
up for the latter is an effective strategy for maintaining therapeutic range. Treating
“antibiotics” as a class of medications in relation to warfarin management is not sufficient.
An additional understanding of pharmacologic principles must be applied to improve
outcomes.
The nurses confirmed the need for additional education surrounding medication
interaction at the second focus group. They also identified a need for additional decision
support tools to assist them in making dose determinations and follow-up instructions when
there are potential medication interactions.
EVALUATION OF ANTICOAGULATION CLINIC 62
As it is impractical to create a protocol for every potential medication interaction with
warfarin therapy, it is necessary to design a more targeted approach to dealing with this issue.
The anticoagulation protocol advised consulting a drug reference to determine the potential
interaction of other drugs. A fairly comprehensive list of common medications along with
their strength and direction of interaction could be developed. It would then be necessary to
give the nurses the authority to make appropriate preemptive dose adjustments in response to
potential significant drug interactions, and to alter the time-to-follow-up plan as necessary.
This will require additional nurse education in the area of pharmacologic principles, and
educational planning strategies are needed. Use of summarized tools that include the
strength and direction of an interaction, such as the tables presented in Holbrook et al.
(2005), may prove useful to the nurses in understanding potential medication interaction
issues. These tables could supplement a nurses understanding of potential interactions and
help guide their course of action.
New to warfarin/suspension of therapy. According to Hirsh et al. (2003),
“Warfarin dosing may be separated into initial and maintenance phases. After treatment is
started, the INR response is monitored frequently until a stable dose-response relationship is
obtained; thereafter, the frequency of INR testing is reduced” (p. 1637). Upon investigation
of the clinic protocol, it is strikingly evident that there are no separate instructions for the
initiation of warfarin from the chronic management instructions. The current protocol has a
chronic maintenance algorithm, but does not provide dosing guidelines for the patient naïve
to warfarin. In the clinical audit, the nurses had various recommendations for patients in this
phase of therapy with no standardized approach.
EVALUATION OF ANTICOAGULATION CLINIC 63
Numerous start-up protocols are in existence (e.g. Anderson et al., 2002, Kovacs et
al., 2003, and Dalere, Coleman, & Lum, 1999). Many of the existing acute start-up protocols
have been designed for in-hospital use when the INR can easily be monitored daily, such as
the protocol employed at the clinic‟s affiliated hospital. This in-hospital warfarin protocol
(Northeast Hospital Corporation Pharmacy & Therapeutics Committee, 2010) employs a
basic dosing nomogram with dosing recommendations based on daily INR changes.
Strategies for outpatient initiation of warfarin are numerous and less well defined in the
literature. Trial of a tested and validated start-up protocol would address the current protocol
deficiency in this area; however, no such outpatient tool has been identified in the literature.
The existing protocol does not address management of patients in the perioperative
period. Certainly, the perioperative patient will require assessment by a prescribing provider
for determination of risk and appropriate perioperative anticoagulation management.
Nevertheless, the anticoagulation clinic is lacking a standard of care for these situations that
can guide both the prescribers and the nurses. Development of a standard of care statement
with guidelines for prescribers and clinic nurses will help assure consistency and safety in the
delivery of care to patients in the perioperative period. These standards should be consistent
with the recommendations published jointly by the American Heart Association and the
American College of Cardiology (Hirsh et al., 2003). Although these recommendations do
not provide specific dosing recommendations, they do provide general statements of dosing
principles that the prescriber should consider when determining a dose.
Trending/history. The concept of trending patterns is not well described in the
literature. Numerous anticoagulation protocols utilize dose-response trends in the acute
phase of anticoagulation initiation. Warfarin initiation protocols will often provide a
EVALUATION OF ANTICOAGULATION CLINIC 64
recommendation to increase the dose for a small INR response early on in therapy, or to
decrease the dose if a rapid response to anticoagulation therapy is observed even if the INR
remains subtherapeutic (e.g. Kayser, 2005). These protocols recognize a trending pattern in
relation to initial doses of warfarin therapy. The practice of monitoring for trending once
chronic therapy has been established is not well studied. Certainly there is a general
recognition of the lag time of INR response in relation to a change in therapy, diet, or other
influencing factors. This understanding notwithstanding, there is no recommendation
provided in the literature for tracking of INR trends when the INR is within therapeutic range
and there is no identified alteration in factors affecting warfarin.
Although no statistically significant difference could be determined when trending
was observed and this factor impacted dosing recommendations, these data need to be
interpreted carefully. The patient data to which the indentified trending cases were compared
are not paired data sets. The cases of identified trending were selected by the nurses as being
at risk for returning out of range, thus the dosing instructions were modified preemptively.
The failure to see a difference in outcomes for the identified trending patients as compared to
other patients may actually be a positive finding in support of this method of decision-
making. The practice of monitoring for and tailoring to patterns of trending may be an
effective strategy in warfarin regulation, and is a topic that requires further research.
Within the second focus group, the nurses identified various applications of the
concept of trending, and recognized the distinction between acute trending and chronic
trending. This area will require further nurse education relating the appropriateness of the
use of trending as a decision-making tool.
EVALUATION OF ANTICOAGULATION CLINIC 65
Dosing calculator ineffective. The dosing calculator does not have the capability of
assessing situations where a weekly dose total does not represent a complete week of
warfarin dosing. Creation of a start-up protocol and a perioperative management strategy are
steps that would be expected to decrease the frequency of this issue.
Holds and missed doses will continue to present particular challenges. The time to
follow-up after a hold is typically shorter due to concerns related to the very high INR that
prompted the hold. At the rapid follow-up visit after hold, the INR will not have reached a
steady state. The INR dosing calculator is only appropriate for use in steady state situations
due to the known acute trending issue with dosing adjustments. As such, a clinical
determination will need to be made as to the appropriate dosing instructions which takes into
account the highest INR value; prior dosing schedule that resulted in the supratherapeutic
state; other influencing factors that lead to the INR elevation, including current and
anticipated future status of these issues; number of days held; number of days since last INR
value; risks for both bleeding and thromboembolic events; and the current INR.
During the second focus group, the nurses reported uncertainty in how to address a
hold and calculate new dosing instructions. They identified that they were confused by the
dosing calculator‟s advice for total weekly dosing when there had been a recent hold. They
also found that documentation of dosing instructions relating to recent holds was a
problematic area for them, and could lead to confusion at subsequent visits. Additional
standards of care need to be developed, and the nurses require further education relating to
this subject. Furthermore, prescriber consultation would be appropriate in these instances.
As stated previously, there were a total of 16 (3.6%) clinic visits in which there was a hold
within the previous week. Although this would have an impact on time resources and
EVALUATION OF ANTICOAGULATION CLINIC 66
provider burden, this was the area that was identified as having the smallest proportion of in-
range INRs, and deserves additional dedication of these resources.
Adherence to therapy and missed doses must be addressed on an individualized basis.
As discussed by Jaffer and Bragg (2003), the missed dose of warfarin is usually reflected in
the INR within 2 to 5 days after the missed dose. Subtherapeutic INRs after missed doses
may be appropriately low, and increasing the weekly dosing schedule would be
inappropriate. INRs within therapeutic range may represent a previously supratherapeutic
INRs, and dose reduction may be an appropriate intervention. As is the case with doses that
were held intentionally, the INR value must be assessed within the clinical context in which
it occurred. More frequent follow-up of these cases is appropriate to determine ongoing
patient adherence to therapy and reassess stability of INR values.
High-risk/concerning factors. Ongoing assessment of patients‟ individual risks
associated with anticoagulation therapy is of critical importance in steps to assure patient
safety on therapy. Lip (2007) highlights that although many diseases associated with stroke
and thromboembolism are more common with increasing age, many conditions associated
with higher risk of bleeding are also more common with increasing age. The nurses were
correct to have additional concerns for patients at higher risk of falling, patients with higher
risk of bleeding, and patient at higher risk for thromboembolic events, and Lip (2007)
recommends “meticulous attention to the degree of anticoagulation” as a strategy to
minimize the risk of complications of therapy. Control of hypertension is highly relevant as
improved blood pressure control reduces the risk of stroke and systemic embolism in patients
on warfarin (Lip, 2007). Incorporating parameters for these high-risk factors into the clinic
may help to improve patient safety and increase the consistency of nurse recommendations.
EVALUATION OF ANTICOAGULATION CLINIC 67
Patient factors and extraneous factors. The nurses managed specific patient-
related factors and extraneous factors on an individualized basis. The literature describes
best practice guidelines for managing dietary factors surrounding vitamin K intake. Patients
with relative low intake of vitamin K tend to have unstable warfarin control, and there is the
suggestion that supplementation of low-dose oral vitamin K may improve control (Valentine
& Hull, 2008). Patient education on the importance of consistent dietary intake of vitamin K
is a key initial step in dealing with these concerns. Clinicians should provide education to
patients regarding therapy through face-to-face interactions, written materials, and other
audio-visual resources that are at an appropriate level for the patients‟ learning needs (Garcia
et al., 2008). Instructions to temporarily increase or decrease vitamin K intake are not
consistent with best practices, and warfarin dosing should be tailored to match the patients‟
intake of vitamin K (Valentine & Hull, 2008). Use of supplemental vitamin K for correction
of critically high INRs is a separate topic of discussion.
In the clinic audit, various patient instructions were detected in relation to vitamin K
intake. Some of the nurses reported that the patients were instructed to increase their intake
of vitamin K. At the second focus group, the nurses reported various patterns of behavior
relating to their instructions on this issue. These reports verified the need for additional
nursing education on appropriate dietary vitamin K instructions.
Group standard. The practice of more frequent follow-up is not entirely
unsubstantiated in the evidence. Although there is a desire to decrease the patient visit
burden and cost of care, this must be balanced with safety. Conversely, very frequent INR
testing can lead to confusing situations with warfarin dosing as the time to achieve a steady
state can be more than several days, and also results in inefficient use of office resources and
EVALUATION OF ANTICOAGULATION CLINIC 68
increases patient visit burden. The optimal frequency of monitoring is dependent on many
factors which include patient compliance, fluctuations in comorbid conditions, alteration of
other medication therapies, changes in diet, and established stability on therapy.
More frequent follow-up visits are often employed to assess patient factors beyond
just INR values, including the development of complications and the appropriate trending of
INR values in extreme out-of-range INR situations. As such the time to follow-up is not
always determined based on when the expected dose changes will reach intended INR
targets. A nurse may request a short time-to-follow-up recognizing that the INR is not likely
to have reached target yet with the intention of physically assessing the patient or assuring
that the INR is trending appropriately. This practice behavior of following-up more
frequently to assure patient safety may have caused certain clinical decision-making factors
to appear less useful in the clinic audit. The audit tool was designed to assess if the
subsequent INR after a dosing recommendation was in-range, and did not account for
situations where the subsequent INR was not expected to be in-range.
As reported in a consensus statement by Ansell et al. (2001), several clinical trials
have suggested that fewer adverse events and increased time in therapeutic range can be
achieved with more frequent monitoring. The nurses‟ shorter time to follow-up as compared
to the protocol recommendations may be appropriate and beneficial to patient outcomes. A
revised protocol should recommend more frequent follow-up appointments when there are
additional factors present that may cause INR values to be unsteady.
The results from the clinic audit did demonstrate that the nurses will accept INRs
within 0.2 outside of range, even without supporting rationales. This finding supports the
nurses‟ report in the focus group of having more lenient ranges. Through the observations
EVALUATION OF ANTICOAGULATION CLINIC 69
made by the PI during the audit process and the reports by the nurses at the second focus
group, a specific thought process relating to goal ranges was identified as a possible
contributor to this issue. The nurses had been targeting the upper and lower limits of the INR
goal range when making dosing decisions rather than the actual target INR which falls in the
middle of those limits. For this reason, the nurses were more likely to accept an INR that
was considered to be just slightly out of range.
The results of the clinic audit demonstrated less favorable control with the longer
return to clinic times for patients with INRs within 0.2 out of range. This demonstrates the
need for more intensive management of patients with INRs out of goal range. The practice
of accepting INRs that are considered to be slightly out of range without an identifiable cause
should not continue.
The finding of less favorable outcomes in patients with shorter than recommended
return-to-clinic times must be interpreted with caution. The first caution is the limited
sample size, and the statistical limitations that relate to this. The second caution is that the
sample has an inherent bias towards instability. The nurses determined that the patients
required more frequent monitoring out of suspicion that the patient has the increased
potential to be out of range. Although the subsequent INR was out of range in 37.9% of the
cases where the follow-up time was sooner than advised by the protocol, by following up
more frequently, the nurses have the potential to correct the INR and increase the time spent
in therapeutic range. Had the nurses followed the recommended return-to-clinic guidelines,
these patients would ostensibly have remained outside of therapeutic range for longer periods
of time, an average of 15 additional days for these specific cases.
EVALUATION OF ANTICOAGULATION CLINIC 70
Previously unidentified issues. The concept of patient illnesses raising cause for
concern in relation to warfarin therapy is supported by evidence in the literature. Not only do
the medications associated with illness often interact with warfarin, the fluctuations of
Vitamin K intake and hypermetabolic effects related to illness can have variable impacts on
anticoagulation stability (Hirsh et al., 2003). Jaffer and Bragg (2003) recommend more
frequent follow-up when there are concerns of illness.
The protocol states that the medical assistants are involved in the assessment and
formulation of a plan of care. These actions fall outside the scope of practice of a medical
assistant, and these instructions do not represent the current operations of the clinic. This
wording must be removed from the protocol.
The 3 mg leeway for adjusting based on available pill strengths is a feature that
allows for off-protocol dosing without detection of the issue. As it is difficult to track when
the pill strength issue is causing a dose change versus the nurse deliberately changing the
dose when it falls within this 3 mg parameter, monitoring adherence to protocol dosing is
made more complicated. A 3 mg variance in dosing is very significant for some patients, and
modification of the protocol to for a smaller total allowable percentage variance from
recommended weekly dose to accommodate pill strength concerns would decrease the
potential impact of this protocol allowance.
The need for a computerized, automated tracking system is evident, as there were
identified cases of patients being lost to follow-up through the audit process. A
recommendation of the consensus statement from the Anticoagulation Forum is that an
efficient system for scheduling and tracking patients should be utilized (Garcia et al., 2008).
During this audit process, the nurses described the significant amount of time that is spent
EVALUATION OF ANTICOAGULATION CLINIC 71
manually tracking patients, and they expressed concerns over possible oversights that can
occur in their tracking procedures.
Summary and recommendations. All of the findings of this evaluation process
have confirmed the assumption that clinician assessment and judgment are vital to assuring
the quality and safety of an anticoagulation program. Wittkowsky, Spinler, Dager, Gulseth
and Netescu (2010) explained that, “it is simply impossible to construct a mathematically
based warfarin dosing protocol that calculates a dose for every clinical scenario.” The
authors advocate for implementation of dosing guidelines rather than protocols that adhere to
strict nomograms for dosing decisions. Anticoagulation guidelines may suggest doses that
may be appropriate, but Wittowsky et al. stress that “the responsible clinician needs to ensure
that any guideline-suggested dosage is appropriate for the specific situation before any
dosage is prescribed” (p. 1555). Rich (2010) reported, “A good protocol is created from
evidence-based medical practices agreed on by medical staff involved in anticoagulation
therapy (i.e., all stakeholders) and addresses key decision points and respective courses of
action integrated with the clinical judgment and experience of the practitioner” (p. 1557).
From the findings of the various stages of this program evaluation, numerous action
items have been developed (see table below). These items have been categorized according
to the following headings: Tracking and quality assurance; Documentation of care; Protocol
revisions; and Areas for nursing staff and clinic development. Tracking and quality
assurance items relate to the development of systems that will maintain a process patient
tracking and quality monitoring that was previously lacking in the clinic. Documentation of
care items relate to improved communication of nurses‟ rationales as well as other critical
patient care information. Protocol revisions items relate to identified deficiencies in the
EVALUATION OF ANTICOAGULATION CLINIC 72
existing protocol that require the development of new or improved algorithms for dosing.
Areas for nursing staff and clinic development items are issues that were identified as being
problematic that require additional staff education and enforcement of existing standards of
clinic operations. Key participants have been identified for each of these action items, and a
timeline for phases of implementation has been developed (see Proposed Phases of
Implementation table below). Through critically assessing the anticoagulation clinic policies
and procedures, applying additional evidence-based changes to the protocols, and involving
all stakeholders in the process, consistency of care and quality of care provided may improve.
EVALUATION OF ANTICOAGULATION CLINIC 73
Process Improvement Recommendations
Tracking and quality assurance.
Address goals of improving safety and decreasing nurse workload
1. Develop tracking system for quality assurance measures of time in
therapeutic range and complications of therapy
2. Develop patient tracking system in EMR for adherence to follow-up
Documentation of care.
Address goals of improving safety and decreasing physician workload
1. Improved documentation of indication for therapy
2. Improved documentation of expected duration of therapy (with date of
initiation of therapy)
3. Improved documentation of patient factors affecting current INR
4. Improved documentation of rationales for varied dosing instructions
Protocol revisions.
Address goals of improving safety, and decreasing need for physician involvement
and nurse workload
1. Address issue of dosing calculator 3.0 target goal of 2.4-3.6
2. Incorporate start-up protocol for warfarin-naïve patients
3. Incorportate standards for peri-operative management
4. Develop parameters for abnormal vital signs and laboratory data with
guidelines for course of action
5. Incorporate RN authority to adjust recommendations in response to
medication interactions and other influencing factors
6. Incorporate advise for dosing after hold within previous week
Areas for nursing staff and clinic development.
Address goals of improving safety and decreasing visit burden
1. Address issue of numerous (non-standard) INR goal ranges
2. Enforce requirement for specialist evaluation upon enrollment to clinic
3. Address issues of preemptive dose adjustment and frequency of
follow-up for various medication interactions
4. Advise for increased frequency of follow-up for patients with
increased potential for INR fluctuations
5. Further education regarding concept of trending and when it may be
appropriate to apply
6. Education on need to stop practice of accepting INRs out of range as
normal without documentation of appropriate rationale. Also,
education on need for closer monitoring of these patients.
7. Standardize dietary vitamin K recommendations provided to patients
8. Additional nursing education regarding pharmacologic principles of
medication interactions
EVALUATION OF ANTICOAGULATION CLINIC 74
Proposed Phases of Implementation
Phase Milestone Participants Target date of
completion
1 1. Incorporate start-up protocol
for warfarin-naïve patients
2. Incorportate standards for peri-
operative management
3. Develop tracking system for
quality assurance measures of
time in therapeutic range and
complications of therapy
4. Develop patient tracking
system in EMR for adherence
to follow-up
5. Nurse education plan for
development items
2,3,4,5,6,7,8
6. Revisions to protocol for items
1,4,5,6
7. Create plan for revision of
non-standard INR ranges
1. NWS, DES
2. NWS, DES
3. NWS, DES,
LG, IT
Consultants
4. NWS, DES,
LG, IT
Consultants
5. NWS, RNs
6. NWS, DES
7. NWS, DES
4/1/2011
2 1. Nurse education on protocol
revisions and implementation
of revisions into clinic practice
2. Non-standard INR ranges
corrected
1. NWS, RNs
2. NWS, RNs
4/15/2011
3 1. EMR tracking system
implemented and employed by
nurses
1. NWS, DES,
LG, IT
Consultants,
RNs
5/1/2011
4 1. Formal review of all phases of
process improvement and
evaluation of clinic
performance – first of new
practice of quarterly reviews
1. NWS, DES,
RNs
6/1/2011
EVALUATION OF ANTICOAGULATION CLINIC 75
Tables and Graphics
Table 1
Demographics of Clinic Nurses
Participant Education # of years
as nurse
# of years
working at The
Medical Group
# of years
regulating
warfarin
1 RN 3 Year Diploma-1965 45 years 31 years 20+
2 Associate Degree - 1992 18 8 years 8
3 Associate Degree-1991 19 years 9 years 9
4 Bachelors of art-2005
Accelerated Nursing program-
2009
< 1 year < 1 year < 1
EVALUATION OF ANTICOAGULATION CLINIC 76
Table 2
Participant Quotes from Focus Group 1
Factors affecting nurse decision-
making
Participants Comments
Medication Interactions
Antibiotics
Amiodarone
Prednisone
Chemotherapuetics
Blood products
“You‟re stopping somebody‟s Amiodarone.
What‟s the protocol? Do you wait til it turns
downward or do you cut „em then? …. same
with antibiotics – you do not always know how
they are going to affect individual people so is
it better to anticipate the change or to wait for
the change?” (C).
“If someone is started on a new med or a med‟s
changed, knowing what day, how long after
they have started that drug we need to see him
in the clinic to make an adjustment?”
“Do you make any dose adjustments based on
the fact that they are starting antibiotics? (PI)*
“No” (B).
New to warfarin/suspension of
therapy
Patients new to warfarin
Perioperative period
Suspension of therapy
“New patients on Coumadin just can‟t fall into
the protocol. They just can‟t.” (A).
“If they‟ve restarted after a procedure, we‟ll
check them sooner” (D).
“They were started on it 3 days ago and they
went from a 1.1 to a 2.8. You‟re definitely
going to dose down that one” (C).
We want at least 1 or 2 weeks of a steady
leveling before we‟ll let them go 4” (A).
EVALUATION OF ANTICOAGULATION CLINIC 77
Trending/patient history
Assessment of previous INR
values
Trending
Labile responses to dose
adjustment
History of variances
Previous INR response to
medication
“Sometime we look at a history on their
flowsheet to see what goes on when this
happens before. And it takes a while you look
back and say, well the last time they were off
their Coumadin for a surgical procedure, thus
and so happened and it‟s happening again. You
might bet that‟s gonna happen again with this
person. And again, part of it unfortunately is an
educated guess at that point (A).
“What prompts you to question return to
clinic?” (PI) “trending up or down” (C).
“Where one patient you would change it 1% ,
and she goes through the roof or drops so you
have to look at the flowsheet and see how she
responded” (D).
“Sensitivity of knowing that even though they
are outside of range, dropping „em 1-mg a week
might make him sub-therapeutic “ (C).
Dosing calculator ineffective
Previous hold
INR check less than one week
apart
So if you had a hold in the previous week, the
calculator you have to put in the dose for the
previous week and if it includes a hold (B:
Mmmmm), then it (C: right) really messes up..”
(D). “Well it is a true previous week total, but
it doesn‟t account for that one day that you have
them skip it” (C) “Exactly” (B).
“I‟m just thinking you really can‟t use that
calculator if do have someone come in on a
Monday and then you see them again on
Thursday, you‟re not gonna get an accurate
reading, you just can‟t” (A).
“This patient was 4.22 for no reason so we did a
hold and in one week later he had dropped to
2.86 which was within range and the protocol
EVALUATION OF ANTICOAGULATION CLINIC 78
say stay the same for four weeks. However
there was a hold in the previous dosing so then
we had to adjust her week dose not to include a
hold, but we didn‟t want it to be as high as it
was before because she had jumped so much.
So we did (make an adjustment), instead of
bringing her back in four weeks with no
change, because she was in range, we changed
it and we brought her back in one week“ (D).
High risk/concerning factors
Symptomatic patients
History of bleeding
Risk for fall
Risk for stroke
Upcoming cardioversion
Abnormal vital signs or Labs
“Be a little more aggressive with a valve” or “a
stroke” (A).
“If they have a history of a bleed, also we‟ll
check it sooner (A).
“You‟re trying to keep somebody therapeutic
for cardioversion, you‟re gonna check them
weekly” (C).
Patient factors and extraneous
factors
Compliance
Missed doses
Weekends/Holidays
Dietary changes
Self adjustment
Pill strength/prefilled blister packs
“Weekends are a challenge on antibiotics” (C).
“They don‟t want it – they won‟t take 4 weeks.
I guess you have to consider their comfort level
with this too”
“So when the summer especially if patient start
eating a lot of greens, um if people drink a lot
of alcohol and now they are trying to cut down
on their alcohol use…” (D). And how would
that cause you to question the protocol? (PI). “
Because if you know that the cause is going
away, they have a lot of greens last week but
now they‟re going to go back to their normal
diet” (C).
“You‟re also making a change based on what
EVALUATION OF ANTICOAGULATION CLINIC 79
strength pills they have and what increments
you can work with. So if working in 2.5 mg
increments, that‟s what the patient has to work
with without trying to be too confusing to them.
And give them 10 strength pills” (C).
“And if you are worried about compliance?”
(PI). “We check sooner” (D) “Yes” (B).
Group standard
Unfamiliar with protocol
Own parameters
“If somebody came into clinic and they have
only been back on the Coumadin one day,
umm, and they‟re pretty low I might let them go
a week – Actually, I don‟t even know what it
says on that” (C) “no it says two weeks” (A).
“If person has been stable for you know months
and they have an INR at 3.2 the protocol would
tell you to make a dose adjustment but
oftentimes we won‟t make, won‟t want to do
the adjustment and (instead) check them soon.”
(D) “Mmm hm” (C).
“It‟s kinda like if your‟re seeing it‟s 3.1 and you
drop it, you‟re gonna drop them too low.
Especially if someone tends to be 3.1, 3, 3.1”
(A).
“ If somebody stays on the higher side and
they‟re normal and no major changes, then I‟d
leave them up to a 3.3” (C)
EVALUATION OF ANTICOAGULATION CLINIC 80
Table 3
Description of Patient Visit Presentations
Total Visits 421
Individual patients 256
Presenting INR in-range 267 visits (63.4%)
Presenting INR within 0.2 of range 58 visits (13.8%)
Presenting INR above range 53 visits (12.6%)
Presenting INR below range 101 visits (24%)
EVALUATION OF ANTICOAGULATION CLINIC 81
Table 4
Comparison of Patient Presentations across Months
November December
# Patient visits 411 421
INR in-range 265 (64.5%) 267 (63.4%)
INR within 0.2 of range 99 (22.4%) 58 visits (13.8%)
EVALUATION OF ANTICOAGULATION CLINIC 82
Table 5
Listed Indications for Therapy
Indication Total Visits
Atrial Fibrillation (AF) 297 (70.5%)
Mechanical Valve Replacement (MVR) 23 (5.5%)
Pulmonary Embolism (PE) 29 (6.9%)
Deep Vein Thrombosis (DVT) 22 (5.2%)
Cerebrovascular Accident (CVA) 34 (8.1%)
Hypercoaguability 3 (0.7%)
Coronary Artery Disease (CAD) 10 (2.4%)
Peripheral Vascular Disease (PVD) 3 (0.7%)
EVALUATION OF ANTICOAGULATION CLINIC 83
Table 6
Listed Goal Ranges
Goal Range Total Visits
2.0 – 3.0 376 (89.3%)
2.5 – 3.5 24 (5.7%)
3.0 – 3.5 4 (1%)
3.0 – 4.0 4 (1%)
2.0 – 2.5 11 (2.6%)
1.5 – 2.5 1 (0.2%)
1.8 – 2.2 1 (0.2%)
EVALUATION OF ANTICOAGULATION CLINIC 84
Table 7
Number of Decision-Making Factors Present per Patient Visit
# Considerations* Frequency (# cases) Percent (%)
0 199 47.3
1 111 26.4
2 60 14.3
3 32 7.6
4 13 3.1
5 2 0.5
6 3 0.7
7 1 0.2
*Considerations refer to the individual decision-making factors identified by the nurses by
category on the audit form
EVALUATION OF ANTICOAGULATION CLINIC 85
Table 8
Participant Quotes from Focus Group 2.
Category Participants Comments
Agreement with findings “The problem is that it doesn‟t tell you how
badly the interaction is and how many days, and
it doesn‟t give you any guidance” (D).
“She went 3.4, 3.2, 2.9, 2.3. So that‟s what I was
looking at. But that‟s over a 2 month time
period” (B).
“If you look at the flow sheet, this is where he
was 3.8 and then, yup. Well it‟s deceiving
because it looks like the dose was increased, but
it really was just plugging in that hold” (B).
“Sometimes it depends on the chat that you‟re
having with the patient” (A).
“Absolutely. But I even notice myself, I‟ll look
back and I‟ll go, “Who the hell did that?!” And
I‟ll go, oh, I did it! You know, and I would
never have done that today, but geez, but they
made me do it then” (B).
“But I think what we are looking at is the 2.5 to
3.5, and saying, “3.5 is fine,” So what is 3.8?
That‟s fine. And that‟s where we‟re seeing it,
and that‟s how we have been doing it all along”
(A).
“And 1.9 doesn‟t get me too excited because
they‟re still pretty close” (A).
“I have not looked at it as 2-3 seeing 2.5. I have
not” (A).
“And that‟s why I can understand accepting
ranges, but it‟s almost like we should just be
saying TARGET 3.0. Okay if you are 2.5 to 3.5,
but TARGET is …” (B).
“They‟ll say oh geez, I want to increase my
greens when can I do it? And then, okay you‟re
2.8 today, now‟s a good time. Or you‟re 3.3,
today‟s your day” (B).
“I will write preference versus instructed in my
notes, or I try to…” (B).
“Yeah, and looking at this today, this is the other
thing is, even myself, I can look at the same case
two different days and do two different things
EVALUATION OF ANTICOAGULATION CLINIC 86
with it Umm, and yeah, today I would say no, I
probably would have just left it alone and
checked it again in 3 weeks. So it depends on
which way the wind‟s blowing that day on how I
do things sometimes” (B).
Documentation hindrances “And there‟s also the flow of clinic. Already this
patient is up and walking away, I start to
document, and this one is already talking to me
about, you know, what they did last week. So
it‟s, you don‟t have that down time in the
middle” (B).
“In Coumadin Clinic, that‟s our biggest issue”
(A).
“It‟s confusing to read the note. I appreciate us
coming in and seeing it” (C).
“But in all honesty, I don‟t often, and I can‟t
even imagine writing that the dose was held last
visit when you‟ve got it right there on the flow
sheet. I‟m kind of writing things that aren‟t
apparent from the flow sheet. I assume that you
can see that, that it was held” (B).
“And also have all of the providers on the same
page about where they want us to put the
information” (D).
“That‟s gonna take a lot more concentration”
(B).
“I‟m overwhelmed sitting here right now
because you have no idea how many of those
make sure you click that button, make sure you
report the INR, you know what I mean?” (B).
“Again we‟re down to a very very small fraction
of the time being seeing the patient” (A).
“It‟s like plenty of time when things are going
well, and when you‟ve got 5 people that come in
that are way off track and everything‟s
happening to them, and that‟s how you don‟t
chart sometimes” (A).
“Unfortunately, if we write a lot of that into the
note now, the patient receives that also. It‟s part
of his instructions” (A).
“I‟ve seen examples of different documentation
from different clinics where there‟s areas, you
know, different questions that you have to ask to
make sure that you kind of document, like makes
you include it in the note” (D).
EVALUATION OF ANTICOAGULATION CLINIC 87
EMR deficiencies “These are the things that drive us out of our
minds. Because even just trying to figure things
out, that day I‟m trying to read it across and I
would have been looking at total weekly doses,
and when you realize they don‟t match…” (B).
“[I] think a lot of the problem with me is
computer program. Because we are always
having to fix something. Something doesn‟t
come out in the flow sheet, something doesn‟t
come out show up. We spend more time
babysitting the computer sometimes than we do
with the patient” (A).
Engrained patterns of behavior “I don‟t think patients who have been on it a
long time are going to come back sooner. I don‟t
think the compliance will be there” (A).
“It‟s tough to teach an old dog new tricks” (B).
EVALUATION OF ANTICOAGULATION CLINIC 88
Table 9
Direction of dose change
Total
Number of
Patients
Dose
Maintained
Dose Increased Dose
Decreased
Presenting INR In-
Range
267 229 (85.8%) 24 (9%) 14 (5.2%)
Presenting INR
within 0.2 Above
Range
23 11 (47.8%) 0 (0%) 12 (52.2%)
Presenting INR
within 0.2 Below
Range
35 14 (40.0%) 18 (51.4%) 3 (8.6%)
Presenting INR
Above Range
52
29* 14 (26.9%)
3 (10.3%)*
0 (0%)
0 (0%)*
38 (73.1%)
26 (89.7%)*
Presenting INR
Below Range
102
67*
33 (32.4%)
19 (28.3%)*
64 (62.7%)
46 (68.7%)* 5 (4.9%)
2 (3.0%)*
*excluding values within 0.2 out-of-range
Bold value indicates off-protocol dosing
EVALUATION OF ANTICOAGULATION CLINIC 89
Figure 1
Model of Factors in Nurse Decision-making
EVALUATION OF ANTICOAGULATION CLINIC 90
Figure 2
Conceptual Design of Project
EVALUATION OF ANTICOAGULATION CLINIC 91
Appendices
Appendix A: Timeline of Events
August 31st Milestone: Proposal Accepted and IRB Release Obtained
September 27th
Milestone: 1st round of focus groups complete
Participants: Clinic Staff including: RNs, MAs, MD
Organizer: PI
Method: Audio recording of focus group w/ objective of identifying
concepts of quality of care that are important to the anticoagulation
clinic and problematic clinical situations that will help in the
development of a comprehensive audit tool.
November 17th
Milestone: Results of focus group compiled and verified by
participants
Participants/Method: Compilation of data from focus group by me.
Key markers of factors derived from this process will be included in
comprehensive audit tool.
Audit tool will be reviewed by the focus group for content validity
marking
December 1st Milestone: Data collection begins
Participants: Clinic RNs will complete audit tool with each patient
visit.
January 1st Milestone: RN Data collection complete. Follow-up audit begins
Participants: PI and MSN student
February 10th
Milestone: Data collection complete
February 23rd
Milestone: Compiled data reviewed by focus group
Method: Data analysis of audit performed by PI. Results compiled
and necessary charts pulled for focus group review.
Discussion/analysis of data w/ focus group to determine cause of
variation from protocols without clear reason documented. Analysis
of all cases with variation from protocols for validity as compared to
evidence in literature, and assessment of outcomes.
March 1st Milestone: Final Assessment and Recommendations reviewed by
participants. Evaluation presented to Medical Director.
Method: Assessment of data from audit and second focus group.
Review of literature for supporting evidence.
April 1st Milestone: Revised anticoagulation protocol implemented
May 1st Milestone: Data tracking system in place
Method: Modifications to EMR system with IT support
EVALUATION OF ANTICOAGULATION CLINIC 92
Appendix B: Informed Consent
PURPOSE OF PROJECT
I have been informed that this process improvement project will investigate the benefits and limitations of the
existing Anticoagulation Protocol utilized the nurses at The Medical Group, Inc. This project will help direct
efforts for improvements in the protocol.
PROCEDURE
I understand that I will be participating in a series of focus group sessions. During these sessions, I will be
asked to provide feedback on various aspects of the Anticoagulation Clinic. These sessions will be audio taped
and transcribed. During this process, information about my clinical experience, as well as certain demographic
data about me will be obtained. I will be reviewing the summaries of the transcribed data before they are
published to assure accuracy of the findings.
RISKS AND DISCOMFORTS
I understand that discussion of clinical situations in the group settings is not anonymous. Anything said during
these sessions is being shared with all of those present, including supervisors or administrators. No names will
be published or made available to those not actively participating in the project; however, complete anonymity
in compiled data may not be possible due to the limited number of participants, and the open-identities of
providers in the clinic.
BENEFITS
I understand that participation in this project will have no direct benefit to me other than the potential for having
my concerns heard in the improvement process, and my ideas incorporated into revised clinic protocols.
CONFIDENTIALITY
I understand that sensitive, personal information will not be included in any publication.
REQUEST FOR MORE INFORMATION
I understand that I may ask more questions about this project at any time. Nathan Samuels at x7192 is available
to answer my questions or concerns. If during the project, or later, I wish to discuss my participation in or
concerns regarding this project with a person not directly involved, I am aware that Dr. Susan Neary, Director
of the Doctor of Nursing Practice program at Simmons College (617-521-2140) is available to talk with me. A
copy of this consent form will be given to me to keep for my own records.
REFUSAL OR WITHDRAWAL OF PARTICIPATION
I understand that my participation is voluntary and that I may refuse to participate or may withdraw consent and
discontinue participation in the project at any time without jeopardy to my employment status at The Medical
Group. I also understand that Nathan Samuels may terminate my participation in this project at any time after
he has explained the reasons for so doing.
ATTESTATIONS
I have explained to __________________________ the purpose of the project, the procedures required, and the
possible risks and benefits to the best of my ability.
__________________________________ ___________
Investigator Date
I confirm that Nathan Samuels has explained to me the purpose of the project, the investigation procedures that
I will undergo, and the possible risks as well as benefits that I may experience. I have read and I understand this
consent form. Therefore, I agree to give my consent to participate in this research project.
__________________________________ ____________
Participant Signature Date
EVALUATION OF ANTICOAGULATION CLINIC 93
Appendix C: Confidentiality Agreement
Transcription Services
I, ________________________, transcriptionist, agree to maintain full confidentiality in regards to any and all audiotapes and documentation received from Nathan Samuels related to his doctoral study on Evaluation of a Nurse-Managed Anticoagulation Clinic. Furthermore, I agree:
1. To hold in strictest confidence the identification of any individual that may be inadvertently revealed during the transcription of audio-taped interviews, or in any associated documents;
2. To not make copies of any audiotapes or computerized files of the transcribed
interview texts, unless specifically requested to do so by Nathan Samuels;
3. To store all study-related audiotapes and materials in a safe, secure location as long as they are in my possession;
4. To return all audiotapes and study-related documents to Nathan Samuels in a
complete and timely manner.
5. To delete all electronic files containing study-related documents from my computer hard drive and any backup devices.
I am aware that I can be held legally liable for any breach of this confidentiality agreement, and for any harm incurred by individuals if I disclose identifiable information contained in the audiotapes and/or files to which I will have access. Transcriber’s name (printed) ___________________________________________________ Transcriber’s signature ________________________________________________________ Date ______________________________________________________________________
EVALUATION OF ANTICOAGULATION CLINIC 94
Appendix D: Focus Group Guide (Session 1)
1) What are some common reasons you might find it necessary to challenge the clinic
protocol?
2) What parts of the clinic protocols do you find to be most problematic when regulating
warfarin dosing?
3) What types of clinic situations that are not already included in the clinic protocol
would cause you to seek assistance or question the dosing recommendations as
provided in the protocol?
4) What clinical situations would cause you to question the dosing recommendations as
provided in the protocol when a patient‟s INR is subtherapeutic?
5) What clinical situations would cause you to question the dosing recommendations as
provided in the protocol when a patient‟s INR is supratherapeutic?
6) What clinical situations would cause you to question the dosing recommendations as
provided in the protocol when a patient‟s INR is in therapeutic range?
7) What elements do you believe could be incorporated into the clinic protocol that
would enhance patient safety?
8) What elements do you believe could be incorporated into the clinic protocol that
would enhance nurse autonomy?
9) What clinical situations would cause you to have a patient return to clinic sooner than
recommended by the protocol?
10) What clinical situations would cause you to have a patient return to clinic later than
recommended by the protocol?
EVALUATION OF ANTICOAGULATION CLINIC 95
Appendix E: Existing Protocol
EVALUATION OF ANTICOAGULATION CLINIC 96
EVALUATION OF ANTICOAGULATION CLINIC 97
EVALUATION OF ANTICOAGULATION CLINIC 98
EVALUATION OF ANTICOAGULATION CLINIC 99
EVALUATION OF ANTICOAGULATION CLINIC 100
EVALUATION OF ANTICOAGULATION CLINIC 101
EVALUATION OF ANTICOAGULATION CLINIC 102
EVALUATION OF ANTICOAGULATION CLINIC 103
Appendix F: Definition of Terms
Definition of Terms – RN Audit Tool Patient ID
Patient‟s TMG medical record number
The following terms relate to factors that influence the nurse’s warfarin dosing decision.
The nurse should only document factors that affected her decision-making at the
time of the visit. A checkmark on the audit tool indicates that the issue was a factor in decision-making.
A blank on the audit tool indicates that the issue was not a factor in decision-making.
New
Patient is new to warfarin. Patient‟s who have not received warfarin therapy before, and who are
newly enrolled in the anticoagulation clinic.
Peri-op
Patients who are in the peri-operative period.
Bridge
Patients who are being treated with bridge therapy (Lovenox or other injectable) while warfarin
therapy is suspended or while INR is below therapeutic range.
Trending
The recognition of a pattern of INR values increasing (trending-up) or decreasing (trending-down)
Med
Alteration in patient‟s medication plan (other than warfarin).
□ Amiod = Amiodarone □ Antibx = Antibiotic therapy
□ Chemo = Chemotherapy □ Pred = Prednisone
Labile
Patient has a history of variable INR values without clear cause.
Sensitive
Small dose adjustments in the past have caused more severe responses in INR than typically expected
in the average patient.
Prior Tx
The patient has an established pattern of response to a specific dosing schedule that is being used to
guide adjustment
Hold
The patient had been instructed to hold a dose of warfarin in the preceding visit
<1 week
Today‟s follow-up is occurring less than 1 week from the last visit.
Stroke
The patient has a prior history of a stroke, or the nurse considers the patient to be at increased risk for
a stroke. (Specify concern under comments).
EVALUATION OF ANTICOAGULATION CLINIC 104
Bleed The patient has a prior history of a bleed, or the nurse considers the patient to be at increased risk for
a bleed. (Specify concern under comments).
Valve
The patient has a mechanical heart valve.
CVN
The patient is anticipating a cardioversion procedure in the near future.
Vitals/Labs
The patient presents with abnormal lab values or vital signs at the time of the visit. (Specify concern
under comments).
High INR
The INR is alarmingly high to the nurse, and is beyond her comfort level for management without
consultation.
Pt Pref
The patient prefers a different dose or time-to-follow-up than ideally recommended by the nurse.
Diet
The patient has modified dietary habits in a way that is affecting therapy.
Alcohol
The patient‟s consumption of alcohol is thought to be altering therapy.
Missed dose
The patient inadvertently missed a dose of warfarin.
Fixed pills
The patient has limited pill strengths on hand that alter the ideal weekly dosing total.
Weekend/Holiday
Upcoming weekend or holiday interferes with ideal return-to-clinic recommendation.
Pt travel
The patient has upcoming travel plans that may interfere with return-to-clinic recommendation.
Assist. Sought
The nurse seeks guidance on dosing instructions prior to advising patient.
Adverse Event
The patient has experienced a new adverse event since the last clinic evaluation. Adverse events
include major bleeding and thromboembolic events. Major bleeding includes: intracerebral bleed,
bleeding that necessitates suspension or reversal of therapy, bleeding necessitates administration of
blood products, bleeding that leads to death. Thromboembolic events include: thrombotic strokes,
pulmonary embolism (PE), systemic embolism, deep vein thrombosis (DVT)
EVALUATION OF ANTICOAGULATION CLINIC 105
Definition of Terms – Auditor’s Audit Tool
Date/Patient ID
Date of patient visit and patient‟s TMG medical record number
Current INR
INR obtained at point-of-care testing (numerical value)
Goal Range
Target INR range in patient‟s record (numerical value)
In range
Current INR falls within target INR range on record (checkmark indicates „yes‟ – blank indicates
„no‟)
≤0.2out
The current INR falls within 0.2 INR units above or below the target INR range on record
(checkmark indicates „yes‟ – blank indicates „no‟)
Indication
Listed indication for therapy (nominal response)
Protocol Dose
Weekly dose of warfarin recommended by following exisiting protocol (numerical value or nominal
if „hold‟)
Protocol Follow-up
Return-to-clinic time as recommended by following protocol. (numerical value w/ specified
weeks/days)
RN Dose
Weekly dose as recommended by RN (numerical value or nominal if „hold‟)
RN Follow-up
Return-to-clinic time as recommended by RN. (numerical value w/ specified weeks/days)
Protocol Followed
□ Dose – Dosing instructions of RN in agreement with protocol recommendation within 3 mg
□ Follow-up – Follow-up instructions of RN in agreement with protocol recommendation
Follow-up in-range
Subsequent INR at next clinic visit within target INR range (checkmark indicates „yes‟ – blank
indicates „no‟)
Subsequent Adverse The patient experienced an adverse event in the period after the visit up to the next clinic visit.
Adverse events include major bleeding and thromboembolic events. Major bleeding includes:
intracerebral bleed, bleeding that necessitates suspension or reversal of therapy, bleeding necessitates
administration of blood products, bleeding that leads to death. Thromboembolic events include:
thrombotic strokes, pulmonary embolism (PE), systemic embolism, deep vein thrombosis (DVT)
(nominal response).
EVALUATION OF ANTICOAGULATION CLINIC 106
Appendix G: Audit Tools
DATE: ________________ AUDITOR: ________________________
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
Patient ID Current
INR
Goal Range In range ≤0.2out Indication Protocol
Dose
Protocol
Follow-up
RN
Dose
RN
Follow-up
Protocol
Followed
Follow-up
in-range
Subsequent
Adverse
□ Dose
□ Follow-up
DATE: __________________ RN: _____________________
Patient ID
New Peri-op Bridge Trending Med Labile Sensitive Prior Tx Hold <1 week Stroke Bleed Valve CVN
□ Up
□Down
□ Amiod
□ Antibx
□ Chemo
□ Pred
Vitals/ Labs
High INR Pt Pref Diet Alcohol Missed dose
Fixed pills
Weekend/Holiday
Pt travel Assist. Sought
Adverse Event
Other Comments
Patient ID
New Peri-op Bridge Trending up/down
Med Labile Sensitive Prior Tx Hold <1 week Stroke Bleed Valve CVN
□ Up
□Down
□ Amiod
□ Antibx
□ Chemo
□ Pred
Vitals/ Labs
High INR Pt Pref Diet Alcohol Missed dose
Fixed pills
Weekend/Holiday
Pt travel Assist. Sought
Adverse Event
Other Comments
Patient ID
New Peri-op Bridge Trending up/down
Med Labile Sensitive Prior Tx Hold <1 week Stroke Bleed Valve CVN
□ Up
□Down
□ Amiod
□ Antibx
□ Chemo
□ Pred
Vitals/ Labs
High INR Pt Pref Diet Alcohol Missed dose
Fixed pills
Weekend/Holiday
Pt travel Assist. Sought
Adverse Event
Other Comments
EVALUATION OF ANTICOAGULATION CLINIC 107
References
Ahmed, Stephens, Kaus, & Fay. (2008). Impact of preemptive warfarin dose reduction on
anticoagulation after initiation of trimethoprim-sulfamethoxazole or levofloxacin.
Journal of Thrombosis and Thrombolysis, 26(1), 44-48.
Anderson, R. J. (2004). Cost analysis of a managed care decentralized outpatient pharmacy
anticoagulation service. Journal of Managed Care Pharmacy: JMCP, 10(2), 159-165.
Anderson, D. R., Wilson, S. J., Blundell, J., Petrie, D., Leighton, R., Stanish, W., et al.
(2002). Comparison of a nomogram and physician-adjusted dosage of warfarin for
prophylaxis against deep-vein thrombosis after arthroplasty. The Journal of Bone and
Joint Surgery.American Volume, 84-A(11), 1992-1997.
Ansell, J., Hirsh, J., Dalen, J., Bussey, H., Anderson, D., Poller, L., et al. (2001). Managing
oral anticoagulant therapy. Chest, 119(1), 22S-38s.
Baglin, T. P., Keeling, D. M., & Watson, H. G. (2005). Guidelines on oral anticoagulation
(warfarin): third edition 2005 update. British Society for Haematology, 132, 277-285.
Benner, P. (1982). From novice to expert. The American Journal of Nursing, 82(3), 402-407.
Benner, P., & Tanner, C. (1987). Clinical judgment: How expert nurses use intuition. The
American Journal of Nursing, 87(1), 23-31.
Centers for Disease Control and Prevention. (2005). CDC Evaluation Working Group
[Graphic model]. Retrieved from http://www.cdc.gov/eval/framework.htm.
EVALUATION OF ANTICOAGULATION CLINIC 108
Chiquette, E., Amato, M. G., & Bussey, H. I. (1998). Comparison of an anticoagulation
clinic with usual medical care: Anticoagulation control, patient outcomes, and health
care costs. Archives of Internal Medicine, 158(15), 1641-1647.
Cohen, D.J., & Crabtree, B.F. (2008). Evaluative criteria for Qualitative research in health
care: Controversies and recommendations. Annals of Family Medicine, 6(4), 331-339.
Conly, J. M., & Stein, K. (1992). The production of menaquinones (vitamin K2) by intestinal
bacteria and their role in maintaining coagulation homeostasis. Progress in Food &
Nutrition Science, 16(4), 307-343.
Connor, C. A., Wright, C. C., & Fegan, C. D. (2002). The safety and effectiveness of a nurse-
led anticoagulant service. Journal of Advanced Nursing, 38(4), 407-415.
Dalere, G. M., Coleman, R. W., & Lum, B. L. (1999). A graphic nomogram for warfarin
dosage adjustment. Pharmacotherapy, 19(4), 461-467.
Fitzmaurice, D. A., Kesteven, P., Gee, K. M., Murray, E. T., & McManus, R. (2003). A
systematic review of outcome measures reported for the therapeutic effectiveness of oral
anticoagulation. Journal of Clinical Pathology, 56(1), 48-51.
Garcia, D. A., Witt, D. M., Hylek, E., Wittkowsky, A. K., Nutescu, E. A., Jacobson, A., et al.
(2008). Delivery of optimized anticoagulant therapy: Consensus statement from the
anticoagulation forum. The Annals of Pharmacotherapy, 42(7), 979-988.
EVALUATION OF ANTICOAGULATION CLINIC 109
Hirsh, J., Fuster, V., Ansell, J., & Halperin, J. L. (2003). American heart
association/American college of cardiology foundation guide to warfarin therapy.
Circulation, 107(12), 1692-1711.
Holbrook, A. M., Pereira, J. A., Labiris, R., McDonald, H., Douketis, J. D., Crowther, M., et
al. (2005). Systematic overview of warfarin and its drug and food interactions. Archives
of Internal Medicine, 165(10), 1095-1106.
Jaffer, A. & Bragg, L. (2003) Practical tips for warfarin dosing and monitoring. Cleveland
Clinic Journal of Medicine, 70(4), 361-371
Kayser, S. R. (2005). Practical challenges in the management of oral anticoagulation.
Progress in Cardiovascular Nursing, 20(2), 80-85.
Kim, H. S. (1983). The nature of theoretical thinking in nursing. East Norwalk, Conn.:
Appleton-Century-Crofts.
Kim, Y., Niewlaat, R., Connolly, S. J., Schulman, S., Meijer, K., Raju, N., et al. (2010).
Effect of a simple two-step warfarin dosing algorithm on anticoagulant control as
measured by time in therapeutic range: A pilot study. Journal of Thrombosis &
Haemostasis, 8(1), 101-106.
Kovacs, M. J., Rodger, M., Anderson, D. R., Morrow, B., Kells, G., Kovacs, J., et al. (2003).
Comparison of 10-mg and 5-mg warfarin initiation nomograms together with low-
molecular-weight heparin for outpatient treatment of acute venous thromboembolism. A
EVALUATION OF ANTICOAGULATION CLINIC 110
randomized, double-blind, controlled trial. Annals of Internal Medicine, 138(9), 714-
719.
Kreuger, R.A. (1994). Focus groups: A practical guide for applied research (2nd
Ed).
Thousand Oaks, CA: SAGE Publications
Lip, G. Y. (2007). Anticoagulation in older adults. UpToDate Online. Last literature review
version 16.3
Niiranen, S. T., & Yli-Hietanen, J. M. (2008). Analysis of computer-supported oral
anticoagulant treatment follow-up workflow. Conference Proceedings: ...Annual
International Conference of the IEEE Engineering in Medicine and Biology
Society.IEEE Engineering in Medicine and Biology Society.Conference, 2008, 4330-
4332.
Northeast Hospital Corporation Pharmacy & Therapeutics Committee. (2010). Warfarin
sodium (Coumadin) guidelines for oral anticoagulation. October 2010 revision.
Oake, N., Fergusson, D. A., Forster, A. J., & van Walraven, C. (2007). Frequency of adverse
events in patients with poor anticoagulation: A meta-analysis. CMAJ: Canadian Medical
Association Journal = Journal De L'Association Medicale Canadienne, 176(11), 1589-
1594.
O'Cathain, A., Sampson, F. C., Munro, J. F., Thomas, K. J., & Nicholl, J. P. (2004). Nurses'
views of using computerized decision support software in NHS direct. Journal of
Advanced Nursing, 45(3), 280-286.
EVALUATION OF ANTICOAGULATION CLINIC 111
Portney, L. G., & Watkins, M. P. (2009). Foundations of clinical research: Applications to
Practice (3rd
ed.). Upper Saddle River, NJ: Pearson Education, Inc.
Rich, D. (2010). Joint commission‟s requirements for warfarin dosing guidelines. American
Journal of Health-System Pharmacy. 67, 1557.
Sandelowski, M. (2000). Whatever happened to qualitative description? Research in
Nursing and Health, 23, 334-340.
Sandelowski, M. (1986). The problem of rigor in qualitative research. Advances in Nursing
Science, 8(3), 27-37.
Shimabukuro, T. T., Kramer, J., & McGuire, M. (2004). Development and implementation of
a nurse-managed anticoagulation program. Journal for Healthcare Quality: Official
Publication of the National Association for Healthcare Quality, 26(1), 4.
Stading, J. A. (2006). Effects of prednisone on the international normalized ratio. American
Journal of Health-System Pharmacy, 63(23), 2354-2356.
Stewart, D.W., Shamdasani, P.N., & Rook, D.W. (2009). Group depth interviews: Focus
group research. In L. Bickman, & D.J. Rog (Eds.), Applied social research methods (2nd
Ed.) (pp. 589-616). Tousand Oaks, CA: SAGE Publications
The Joint Commission. (2007). 2008 National Patient Safety Goals Hospital Program.
Retrieved from:
http://www.jointcommission.org/PatientSafety/NationalPatientSafetyGoals/08_hap_nps
gs.htm
EVALUATION OF ANTICOAGULATION CLINIC 112
Thompson, C. (1999). A conceptual treadmill: The need for 'middle ground' in clinical
decision-making theory in nursing. Journal of Advanced Nursing, 30(5), 1222-1229.
Valentine, K. A. & Hull, R. D. (2009). Therapeutic use of warfarin. UpToDate Online. Last
literature review version 18.1
van Walraven, C., Jennings, A., Oake, N., Fergusson, D., & Forster, A. J. (2006). Effect of
study setting on anticoagulation control: A systematic review and metaregression. Chest,
129(5), 1155-1166.
White, P. & Ferszt, G. 2009. Exploration of nurse practitioner practice with clients who are
grieving. Journal of the American Academy of Nurse Practitioners, 21, 231-240.
Wilt, V. M., Gums, J. G., Ahmed, O. I., & Moore, L. M. (1995). Outcome analysis of a
pharmacist-managed anticoagulation service. Pharmacotherapy, 15(6), 732-739.
Wittkowsky, A. K., Spinler, S. A., Dager, W., Gulseth, M. P., & Nutescu, E. A. (2010).
Dosing guidelines, not protocols, for managing warfarin therapy. American Journal of
Health-System Pharmacy, 67(18), 1554-1557.
Wofford, J. L., Wells, M. D., & Singh, S. (2008). Best strategies for patient education about
anticoagulation with warfarin: A systematic review. BMC Health Services Research, 8,
40-40.