Best Practice & Research Clinical Obstetrics and Gynaecology 25 (2011) 509–521

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Best Practice & Research ClinicalObstetrics and Gynaecology

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Benchmarking and patient safety in hypertensive disordersof pregnancy

Charlene Thornton, BN, RM, MSc Med (Res), MSc Med (Clin Epi), ClinicalEpidemiologist a,*, Annemarie Hennessy, MBBS, PhD, MBA, Foundation Chairof Medicine a,*, William A. Grobman, MD, MBA, Maternal-Fetal MedicalSpecialist b

aUniversity of Western Sydney, School of Medicine, Sydney, Australiab Institute of Healthcare Studies, Feinberg School of Medicine, Northwestern University, Chicago, USA

Keywords:benchmarkingpatient safetyquality of carepreventable adverse events

* Corresponding authors: Locked Bag 1797, PenrE-mail address: c.thornton@uws.edu.au (C. Tho

1521-6934/$ – see front matter � 2011 Publisheddoi:10.1016/j.bpobgyn.2011.03.002

Hypertensive disorders of pregnancy are a major cause ofmorbidity and mortality worldwide. Reliable, published individualpatient data from units and countries are lacking. Without thesedata, clinicians are unable to benchmark their incidence, treat-ments and outcomes, and patient safety is unable to be routinelyassessed. Available data suggest that a notable proportion of theadverse events that occur with hypertensive disease of pregnancymay be preventable. Theory and practice indicate several methodsthat can offer the possibility of averting these preventable adverseevents. These methods include benchmarking outcomes, stand-ardisation of care processes, simulation, and enhancement ofpatient knowledge. However, data on optimal methods to enhancepatient safety and quality of care of pregnant women withhypertensive disease remain limited, and further research isrequired.

� 2011 Published by Elsevier Ltd.

Benchmarking healthcare: the concept

The use of benchmarking techniques has increased in the healthcare sector since the 1990s. The useof these techniques in health care has largely been pioneered in the USA through the publication ofannual reports such as America’s Best Hospitals annual survey.1 Performancemeasurement systems that

ith South DC, NSW Australia 1797. Tel: þ61 46203682; Fax: þ61 46203681.rnton).

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measure financial performance in non-healthcare sectors have been modified to consider multiplefactors, not just financial benefit (i.e. consumer satisfaction, length of stay and morbidities). The theorybehind the transference of these techniques frommanufacturing to health care is that the latter is alsodriven by improved performance outcomes inwhichmonetary gain is replacedwith lessmorbidity andbetter consumer health.2 It would be naïve to assume that financial performancewas not also at play inthe healthcare sector, as better health care (lessmorbidity, shorter hospital stay) may also equate to lesscost for the healthcare provider. This is a consideration not to be dismissed considering that thehealthcare ‘industry’ comprises 14% of the gross domestic product of the USA2 and 8% in Australia.3

There are many examples of how benchmarking has been used in health care, which highlight thetechniques involved and their effect. On an international scale, the World Health Organization instituteda practical tool to monitor and improve the performance of hospitals.4 The Performance Assessment Toolfor Quality Improvements in Hospitals (PATH) was designed to measure clinical effectiveness, efficiency,staff orientation, responsive governance, safety and patient centredness. Fifty-one hospitals from sixregions completed the initial data collection. Data were compared between countries, but of greaterrelevance between regions of similar economic development. Other benchmarking initiatives, such asthe Acute Physiology and Chronic Health Evaluation (APACHE) model developed in 1993, have targetedspecific service providers, such as intensive care units.5 Now in version IV, APACHE as a statistical modelbenchmarks expected or predicted outcomes and compares them with actual outcomes. This type ofpredictive testing is what fuels the case-mix modelling, and has been incorporated into the AustralianDiagnostic Related Groups framework.6 This type of data collection allows national comparisons to bemade on predicted factors based on patient and hospital profiles.

Benchmarking is also used in disease-specific areas on a regular basis. These initiatives are aimed atmeasuring the performance of individuals,7 units, services, or both.8 Many programmes call them-selves benchmarking without a true understanding of the cyclical process involved. Data on strokerehabilitation,9 pain management10 and diabetes outcomes11 for example, can all be reliably collectedand comparisons made; however, the cyclical process of change implementation and re-evaluationneed to be undertaken to complete the process and allow the full benefit of its power to influencechange in clinical practice.

Benchmarking obstetric morbidity worldwide

United Kingdom

The UK Obstetric Surveillance System12 was established by the National Perinatal Epidemiology Unitand the Royal College of Obstetricians and Gynaecologists in 2005 to monitor rare obstetric conditions(one case per 2000 births). These include amniotic fluid embolism, extreme obesity, myocardialinfarction, pulmonary vascular disease, non-renal solid organ transplant, renal transplant, stroke inpregnancy, failed intubation, malaria, uterine rupture and treatments for postpartum haemorrhage.Reporting to this system is voluntary, and return rates are 87–97% per annum since initiation.

United States of America

The US Center for Disease Control and Prevention reports maternal mortality, rates of hypertension(pregnancy associated) and hypertension (chronic) via the National Vital Statistics Report.13 Thismandatory report on all births in the USA does not include other markers of maternal morbidity.

European Union

In the European Union, perinatal information is collected through a wide variety of methods. Datacollection is compulsory via a specialised birth registry in the following countries: Belgium, the CzechRepublic, Denmark, Estonia, Finland, Germany, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg,Malta, the Netherlands, Norway, the Slovak Republic, Slovenia and Sweden. In Austria, Cyprus, Finland,France, Hungary, Poland, and Spain, birth data are collected from hospital coding systems. France, Italyand Spain regularly conduct surveys to collect perinatal information from medical records and from

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interviews with mothers. The definitions of morbidity vary between each data collection system used,and these methods are best used to monitor mortality rather than morbidity.14

Australia

The National Perinatal Data Collection15 are constructed from data collected under the MidwivesData Collection (MDC). In New South Wales, Australia, data are compiled into the NSW Mothers andBabies Report.16 This mandatorily records every birth 20 weeks’ gestation or over or greater than400 g.17 A limited dataset of events occur during the initial birth hospitalisation. Morbidity data arenon-specific in that severity of complications arising from diagnoses are not recorded. Two validationstudies have been undertaken of the MDC: the first in 199018 and the second in 1998.19 Both studiesconcluded that, although the MDC was accurate in most data fields (i.e. birth date, birth weight andgender), reporting of maternal medical conditions during and before pregnancy needed to improve. Anindependent validation study comparing maternal diagnoses as hand collected and those reported inthe MDC conducted in 2003,20 concluded that the MDC miscoded the type of hypertension womenexperienced in 56% of cases reviewed and under-reported cases of hypertension by 12%.

These type of data include, for example, statistics of the number of women experiencinga complication such as the hypertensive disorders of pregnancy (HDP). The current version of the MDChas the potential to capture the hypertensive diagnoses of chronic hypertension and pregnancy-induced hypertension (proteinuric or non-proteinuric) terminology, which is not in line with thecurrent consensus or previous consensus statements.21 Information is not available on hypertensivemedication prescription, rates of intra-uterine growth-restricted neonates born to hypertensivemothers, maternal complications (i.e. acute renal failure, acute pulmonary oedema), intra-cerebralevents (i.e. stroke), eclampsia, and length of stay variations.

The common theme throughout all of these databases is the recording of the incidence of an event.Databases such as these, for example, can provide information on the number of cases of amnioticembolism but are not necessarily designed for the purpose of benchmarking per se. Some collections,such as the New SouthWalesMothers and Babies Report do compare outcomes between health sectorsor health services within a geographically defined area, but most report on the state or area in whichthey were recorded. The voluntary reporting nature of many of these datasets also limits the validity ofthe data captured. The reliance upon clinicians to report events to mandatory bodies is a furtherlimiting factor in the reliance upon existing datasets to establish standards of clinical care that reflectoptimal outcomes. With a paucity of reliable international or nation-wide information collected onpregnancy outcomes, how are we to assess the efficacy of the service we provide for the most commoncomplication of modern pregnancy.

Worldwide epidemiology of the hypertensive disorders of pregnancy

For such a commonly occurring pregnancy complication, clinical outcomes and incidence of HDPhave not been studied extensively. The oldest printed reference (1935) to an outcome evaluation ofwomen following a hypertensive disorder of pregnancy was by Herrick and Tillman22 of 930 womenover a 15-year period. This study concluded that toxaemia affected women’s long-term vascular healthand shortened their life expectancy. An epidemiological study of pre-eclampsia conducted in 197023

concluded that this disease affected women in all nations, although maternal mortality differedgreatly. A study conducted in the USA over a 12-year period examining 0.7% of births24 concluded thatwomen with pre-eclampsia had a 3–35 fold increased risk of severe complications such as placentalabruption, thrombocytopaenia, disseminated intravascular coagulation, pulmonary oedema andaspiration pneumonia. Outcomes for women with proteinuric compared with non-proteinuric diseasepresentations have also been undertaken25,26 without inclusion of other variations in diseasepresentation and with varying results. A study conducted in 199727 using hand-recorded prospectivepregnancy details for 1183 women diagnosed with the Australasian Society for the Study of Hyper-tension in Pregnancy21 criteria, reported that women with superimposed pre-eclampsia had moresigns and symptoms thanwomenwith other forms of hypertensive diseases of pregnancy and a greaternumber of fetal complications. This finding has been replicated in other studies.28,29

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The outcomes for 4589 women and their babies enrolled in the Calcium for Pre-eclampsiaPrevention Study30 showed that women with hypertension had increased maternal morbidity (i.e.operative delivery, placental abruption and renal dysfunction) and increased neonatal morbidity.

A database study of all womenwho delivered their babies in New SouthWales over a 2-year periodwas undertaken.31 Relying upon the MDC, this study concluded that 9.8% of pregnant women wereaffected by a hypertensive disorder, and that these women suffered greater morbidity and mortalitythan the normotensive cohort. A South Australian study was conducted between 1998 and 2001, whichexamined the outcomes for 5356 hypertensive women over a 4- year period relying upon datacollected via the South Australian perinatal data collection form.32,33 This study compared birth type,delivery gestation and neonatal characteristics such as birthweight, Apgar scores and special carenursery admissions betweenwomenwith pregnancy-related hypertension and thosewith pre-existinghypertension. Women with pregnancy-related hypertension suffered more operative delivery andworse perinatal outcomes. Studies such as these, however do not tell us is that variation in clinicalpractices may have resulted in outcome variation.

The common theme among all of these studies is that inter-unit, inter-state or internationalcomparisons were not undertaken, and although each study adds significantly to our knowledge ofhypertensive diseases of pregnancy at a given time point, none address the issue of outcomeimprovement across time or units.

Can we benchmark outcomes between units and countries in a cohesive meaningful manner?

In an attempt to address these deficits, a statewide and international benchmarking comparisonwas undertaken over a 3-year period between five tertiary referral obstetric units in New SouthWales,Australia, and one unit in Vancouver, Canada.34

Individual patient datawere collected by hand review of medical records of womenwho experienceda viable pregnancy andwhowere recorded as being hypertensive during that pregnancy by standardisedcoding systems (International Classification of Disease 10th edition).35 A series of clinical indicators uponwhich to base comparison were agreed upon for the exercise and applied to this dataset. These includethe following: maternal mortality, acute pulmonary oedema, acute renal failure, eclampsia, perinatalmortality, admission of termneonates to neonatal intensive care units, birthweights (adjusted for genderand gestation) below the 10th and 3rd centile and breast feeding at discharge.

The aim of these indicators was to include a cross-section of maternal, fetal and neonatal measures.The process for indicator establishment was based upon the SMARTmnemonic, originally attributed tothe management consultant Drucker.36

Data were collected in a disorder-specific database, and were validated for inter-rater reliability(K¼ 0.95).

Disorder incidence

The incidence and type of hypertension in the units studied are presented in Table 1. The publishedrate of pre-eclampsia is frequently quoted as affecting 5% of all pregnancies37; however, at the 2010International Society for the Study of Hypertension in Pregnancy, data presented indicated that theincidence of pre-eclampsia is now lower than reported in all developed countries, other than the USA,where the rate is actually increasing. An incidence of 3% of all pregnancies is a more accurate figure inmost nations rather than the 5% previously calculated.38

Diagnostic features

With a plethora of consensus statements available to classify these disorders, the statement of theSociety of Obstetric Medicine of Australia and New Zealand (SOMANZ)21 was applied to the dataset.The SOMANZ consensus statement is more inclusive in parameters and reflects the multi-systemnature of these disorders. The diagnostic features collated using this classification system are pre-sented in Table 2.

Table 1Total number of women with hypertensive and type of hypertension at each unit.

Unit number Total births, 2005 Total hypertensivedisorders of pregnancya

Pre-eclampsiaa Gestationalhypertensiona

Chronic hypertensiona Pre-eclampsiasuperimposed onchronic hypertensiona

N % N % N % N % N %

1 4725 472 10 190 4.0 208 4.5 45 1.0 29 0.52 2902 174 6 60 2.0 77 2.5 26 1.0 11 0.53 3409 374 11 134 4.0 188 5.5 32 1.0 20 0.54 2498 169 7 69 2.5 71 3.0 23 1.0 6 0.55 1969 128 7 50 3.0 57 2.5 12 1.0 9 0.56 7355 409 6 179 2.5 153 2.0 49 1.0 28 0.5All units 22,858 1726 7.5 682 3.0 754 3.0 187 1.0 103 0.5

a Expressed as a percentage of all deliveries.

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Table 2Diagnostic features of women diagnosed with either pre-eclampsia or pre-eclampsia superimposed on chronic hypertension atall units.

Diagnostic feature Pre-eclampsia(% of women)

Pre-eclampsiasuperimposed onchronic hypertension(% of women)

P valuea

Hypertension: systolic blood pressure � 140 mmHg,diastolic blood pressure � 90 mmHg, or both,on two separate occasions 4 h apart, after 20 weeks’ gestation

100 100 NS

Proteinuria: � 300 mg/24 h 77 82 NSRenal insufficiency: serum/plasma creatinine 0.09 mmol/) 10 19 NSLiver disease: abnormal liver function tests or pain 39 18 < 0.001Neurological problems: eclampsia, hyperreflexia with clonus,

severe headache with hyperreflexia, persistent visual disturbance33 25 NS

Haematological disturbance: thrombocytopaenia,disseminated intravascular coagulation, haemolysis

28 10 0.002

Fetal growth restriction 10 8 NS

a Chi-squared comparison; NS, not significant.

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Clinical indicators as instruments of measurement

One clinical indictor was chosen as the focus for further investigation to determine if benchmarkingtechniques can effect practice change. Acute pulmonary oedema rates were targeted for this purpose(Table 3).

Acute pulmonary oedema analysis

An assessment of intravenous fluids given to women in the two settings with the greatest variationbetween rates of acute pulmonary oedema are presented in Table 4.

Logistic regression analytical techniques were applied to evaluate the potential associations. Noother statistically significant factors were found other than the amount of intravenous fluids admin-istered associated with the development of acute pulmonary oedema in this dataset.

This issue was flagged for further intervention. Tighter fluid policies were instituted at unit F, andthe incidence of acute pulmonary oedema was re-assessed in the year after this introduction. Theintravenous fluid volume dropped after the introduction of the new guideline, and the incidence ofacute pulmonary oedema fell from 46 per 1000 to two per 1000 cases.

Quality of care and patient safety

Quality of care can be defined as ‘the degree to which health services for individuals and pop-ulations increase the likelihood of desired health outcomes’.39 Multiple factors contribute to the qualityof patient care, one of which is patient safety. Patient safety can be defined as the absence of thepotential for, or occurrence of, healthcare-associated injury to a patient.39 Patients and their healthcare

Table 3Rates of acute pulmonary oedema.

Unit Number Acute pulmonary oedema per 1000 pregnanciesaffected by hypertensive disorders o pregnancy

A 0/1000B 6/1000C 5/1000D 0/1000E 0/1000F 46/1000

Table 4Comparison of fluid administration for women at each unit.

Unit A(ml)

Unit F: women withacute pulmonary oedema(ml)a

Unit F: women withoutacute pulmonary oedema(ml)a

P valueb

Antenatal fluids administeredc 1000 (1000) 6204a 2400 (2653) c

Intrapartum fluids administeredc 1000 (2875) 4276 (3000) 2775 (2290) < 0.001Postpartum fluids administeredc 1000 (2000) 4625 (4000) 2400 (2803) 0.003Total fluids administeredc 2100 (3000) 910 (6720) 5200 (5688) < 0.001

a Median and interquartile range expressed.b non-parametric testing applied.cfluid volume expressed ml, �, two cases only.

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providers have become increasingly cognisant of both of these concepts (i.e. patient safety as well asthe broader concept of quality care). Although there aremany reasons for this increased awareness, onefactor is likely the information that has been disseminated by the Institute of Medicine in its reportsCrossing the quality chasm and to err is human.40,41 For example, in the latter between 44,000 and98,000 people were reported die in hospitals each year as the result of medical errors.

With obstetric care specifically, evidence shows that at least some of the adverse events that occurare preventable. For example, Berg et al.42 analysed maternal deaths in North Carolina over a 4-yearperiod, and determined that 40% were preventable. White et al.43 analysed closed professionalliability claims relating to obstetric and gynaecological care and found that over 70% were prevent-able. A similar frequency of preventable adverse perinatal events associated with professional liabilityclaims was reported by Clark et al.44 Forster et al.45 used a prospective study design to assess thefrequency of quality problems, defined as either an adverse event or an action with the potential ofcausing an adverse event, on an obstetric unit. In their study, 87% of quality problems were judged tobe preventable.

In addition to assessing whether the adverse events may have been preventable, several of theseinvestigators have also attempted to determine which factors within the health care of the individualcontributed to the adverse events. It is fair to say that these studies have implicated multiple differentcontributing factors at multiple different levels (i.e. the individual level, the group level, the systemslevel). Nevertheless, one factor that has been cited to be frequently, if not most frequently present, isa problem with communication. For example, some type of communication breakdown was noted bythe Joint Commission to be the contributing factor most frequently present in maternal and perinatalsentinel events.46

There is reason to believe that the occurrence of preventable adverse events, and the importance ofcommunication as an aetiological factor for these events, has particular relevance for HDP. This ispartly because these disorders are relatively common (i.e. occurring in about 5% of the population)and accounts for a significant portion of obstetric morbidity and mortality. As reported by Khanet al.,47 HDP are within the top four causes of maternal mortality in developed and underdevelopedregions of the world. Clark et al.48 and Berg et al.,42 examining populations within the USA, found thatHDP were, respectively, the first and the third most common cause of maternal death among theirpopulations. Geller et al.49 examined mortality and morbidity, and showed the significant contribu-tion of pre-eclampsia and other HDP. These investigators found that HDP was the predominant factorin over 10% of maternal deaths, and in 18% of ‘near miss’morbidity cases and 48% of severe morbiditycases. However, ‘near-miss’morbidity, in their analysis, does not connote that a woman nearly misseshaving morbidity, but that she nearly misses having a mortal event. Additionally, evidence shows thatadverse events associated with HDP are not infrequently preventable. Among maternal deaths inNorth Carolina, 60% of those related to HDP were categorised as potentially preventable.42 Gelleret al.49 reported that 45% of cases with ‘near-miss’ morbidity related to HDP were potentiallypreventable. Evidence of preventability can also be gleaned from the racial disparity that exists inrelation to outcomes in HDP. Tucker et al.50 analysed case-fatality rates of different pregnancycomplications, and reported that black womenwere two- to three-foldmore likely to die in the settingof pre-eclampsia or eclampsia than white women. In an effort to demonstrate that this difference was

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not due to differences in the severity of the disease process itself, Rosenberg et al.51 examined onlyhigh-risk women in Illinois and adjusted for patient characteristics, and still found a markedlyincreased probability of death among black or Latina women, compared with white women. In theirstudy of maternal mortality, Berg et al.42 observed the frequency that deaths were potentiallypreventable for different obstetric complications, and also that African–American women weresignificantly more likely to have a preventable cause.

The evidence presented thus far should support the following notions: (1) HDP are responsible fora significant portion of obstetric morbidity and mortality; (2) a notable portion of the obstetricmorbidity and mortality that occurs, in general and specifically with regard to hypertension in preg-nancy, is potentially preventable; and (3) communication and systems-level factors are predominantcauses in preventable adverse events.

Accordingly, attempts to enhance the quality of care, including patient safety, among women withHDP, have often been based upon enhancing communication, both at the provider–provider andprovider–patient levels. Few studies have been published on quality improvement efforts specificallytargeting pre-eclampsia and other HDP, but several studies suggest methods by which quality care andpatient safety can be improved.

Avoidance of medication errors

Medication errors have been described in a variety of medical situations. Kfuri et al.52 detailed thescope of the problem in obstetrics. Simpson and Knox53 presented details about magnesium sulphatethat has particular relevance for HDP. They reported 52 instances in which an accidental magnesiumsulphate overdose occurred. These overdoses were not merely unconnected events related to randomhuman error, but seemed ‘to involve similar themes and causative factors.’ For example, womenreceived the incorrect dose of magnesium because non-standard concentrations and dosing regimenswere used on a single obstetric unit. On the basis of these cases, as well as recommendations from theInstitute of Medicine for best practices for high-risk medications, these investigators proposed severalsystems-level changes that should be adopted to reduce the chance of accidental magnesium sulphateoverdose. Some of their key recommendations included: (1) the implementation of a unit protocol withstandardised, standing orders should be developed for magnesium sulphate administration, includingthe amount of the initial bolus and the maintenance dose to be administered; (2) the avoidance ofindividual and variable orders from each physician for magnesium sulphate administration; (3) theadministration of intravenous magnesium sulphate (including the initial loading dose) only througha controlled infusion device with free-flow protection; (4) the use of universal standardised-dose pre-packaged magnesium sulphate for both the loading dose and maintenance; (5) the avoidance of‘double and triple concentrations’ for fluid restriction; (6) clearly label intravenous bags with easy-to-read large print and colour-coded labels.

Checklists and protocols

One of the themes that run through the recommendations of Simpson and Knox53 for enhancingthe safety of magnesium sulphate administration is the importance of standardisation. The benefitsof standardisation have been theorised for medication administration and a variety of processesrelated to healthcare delivery. Such approaches include protocols and checklists. As explained byHales and Pronovost,54 protocols and checklists differ slightly. Although both are concerned withstandardisation, checklists provide explicit lists of items, an action which is thought to act asa cognitive aid.

One of the most compelling demonstrations of the usefulness of checklists comes from critical carestudies. In their study, Pronovost et al.55 showed that the introduction of a five-item checklist wasassociated with a 66% reduction in the incidence of catheter-related blood stream infections amongpatients in the intensive care unit. The generalisability of this approach was supported by the fact thatthis checklist was introduced across 108 intensive care units throughout Michigan, USA.

The potential benefits of a standardised approach to care processes other than either medicationor central-line administration have been shown as well. One suggestion for the benefits of

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standardisation of HDP management comes from the PIERS study,56 an international collaborativerisk-modelling and management tool. After establishing a set of best practices that were concernedwith the evaluation and surveillance of pregnant women presenting with hypertension, Menzieset al.56 introduced these practices at British Columbia Women’s Hospital. Before the standardisedapproach, 5.1% of women with HDP had experienced the composite end point of adverse maternaloutcomes (maternal death or one or more of hepatic failure, haematoma, or rupture; Glasgow comascore less than 13; stroke; at least two seizures; cortical blindness; need for positive inotrope support;myocardial infarction; infusion of any third antihypertensive drug; renal dialysis or transplantation; atleast 50% FiO2 for greater than 1 h; intubation; or transfusion of at least 10 units of blood products).After the standardised approach was disseminated, the frequency of the composite adverse outcomewas observed to be 0.7%, an 86% reduction (P< 0.001). An adverse perinatal composite outcome(bronchopulmonary dysplasia, necrotising enterocolitis, grade III or IV intraventricular haemorrhage,cystic periventricular leukomalacia, or stage 3–5 retinopathy of prematurity) was also studied, andfound to decrease from 8.8% to 5.9%, although this decrease did not reach statistical significance (OR0.65, 95% CI 0.37 to 1.16).

von Dadelszen et al.57 followed up on this single-centre study with a study evaluating outcomesafter the introduction and active implementation of hypertension in pregnancy guidelines throughoutall of British Columbia, Canada. As in the single-centre study, they found that, after dissemination ofguidelines, the frequency of adverse maternal outcomes among women with HDP decreased (RR 0.60,95% CI 0.48 to 0.75). Combined adverse perinatal outcomes also declined significantly (RR 0.69, 95% CI0.53 to 0.90), although this decreasewas not statistically different than a similar decrease that was seenamong women without HDP of pregnancy over the same time period.

Simulation

Simulation of a given event is an opportunity for healthcare workers to prepare and train forinterventions without exposing themselves or patients to additional risk.58 The potential benefits ofsimulation training, as well as the educational debriefing that occurs once the simulation has beencompleted, have been studied widely in medicine for a multitude of different scenarios.59 This is alsotrue within obstetrics, where training of both routine (e.g. vaginal delivery) and acute (e.g. shoulderdystocia) type of events have been studied.

Eclampsia is an event that is particularly well suited to simulation training or drills. It is a relativelyrare event, but can also occur unpredictably. Consequently, it is unlikely that any provider, even onewho cares for many parturients, will have the opportunity to treat many women with eclampsia.Moreover, the response to an event of eclampsia typically involves an entire care team (e.g. obstetrics,midwifery, nursing, anaesthesia), which needs to work together to optimise outcomes in the setting ofthis uncommon event. Thus, simulation offers the opportunity to gain and maintain both individualand team skills.

Relatively few studies have evaluated whether simulation of eclampsia results in improvedoutcomes. Thompson et al.60 evaluated whether simulation of the response to a patient witheclampsia could improve resuscitations during subsequently simulated eclampsia. In their study,providers were notified that simulations would take place on their unit, but not told specificinformation about the time of occurrence. At a time of the study team’s choosing, providers would benotified that an eclamptic seizure was occurring in a given room on the delivery unit and wereexpected to proceed with the appropriate response. The team’s response was videotaped and theteam’s actions, including the appropriateness and speed of the resuscitations, were analysed. Thesesimulations provided the opportunity to discern, and subsequently rectify, knowledge deficitsamong providers. Furthermore, these simulations allowed the investigators to discover barriers tooptimal care that transcended individual provider skill or knowledge. Specifically, the investigatorsnoted (1) the inability to efficiently summon senior staff; (2) role confusion among team members;(3) the variability in presentation of critical medicines; and (4) the lack of accessibility of thesecritical medicines.

After a unit-wide initiative to resolve each issue (e.g. the rapid notification of senior staff througha single call to the switchboard), simulations were re-initiated. These simulations were notable for

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better patient assessment, more appropriate and timely administration of drugs, and improvedmonitoring of vitals. These improvements were seen even among staff who had not participated in theinitial simulations, thereby demonstrating the improvement was not related solely to practice. Thisexperience illustrates that, in addition to allowing repetition, simulations (particularly when under-taken on an actual care unit) may provide benefits through the elucidation of systems issues.

Ellis et al.61 also examined the effect that training has upon responses to simulated eclampsia,and specifically attempted to estimate the benefit that could be obtained through training on thehospital unit compared with a simulation centre. In their study, teams that responded to a simulatedevent of eclampsia occurred after training with a lecture and simulated eclampsia drill, demon-strated a more rapid (27 s v 55 s, P¼ 0.01) completion of basic tasks, a more frequent administrationof a proper magnesium sulphate loading dose (92% v 61%, P¼ 0.040), and an improvement inteamwork (median global score 4.0 v 2.5, P< 0.001). Participants randomised to training on thehospital unit did no better than those randomised to a simulation centre. However, in contrast to thestudy by Thompson et al.,60 it does not seem that substantive changes were made to the hospitalsystems as a result of the initially observed simulations, thus limiting the potential benefit of theon-unit simulation experience.

No published study has shown that simulation training for eclampsia improves actual patientoutcomes related to eclampsia.

Clinician–patient communication

The discussion thus far has concerned improvements in outcome that may be obtained oncea patient has entered the inpatient system. However, HDP may compromise a woman’s health beforeshe ever transitions to inpatient care. The association between severity of disease and outcome (i.e.women with severe disease have worse maternal and perinatal outcomes than women with milddisease) suggest that, if possible, it is better for women to engage with their care providers and thehealthcare system earlier in their disease process.

Correspondingly, it would be expected that womenwho are cognisant of signs and symptoms thatmay be seen in association with HDP may be able to augment their routine care and enhance theiroutcomes through early presentation. Although not extensive, there is some evidence to suggest thatthis is the case. In a Belgian study,62 investigators examined factors that were associated with womendeveloping severe pre-eclampsia, eclampsia, or haemolysis, elevated liver enzymes and low plateletcount. In addition to well-established factors such as nulliparity and obesity, markers of socialdeprivation, such as ‘no access to national health insurance’ and ‘history of residency in anothercountry’were associated with disease severity. This finding suggested that ‘poor information’, relatedto poor access, could account for the observed association. Ogunyeme et al.,63 examined the medicalrecords of a population of women in Los Angeles, USA, and focused on the preventability of eclampsia.They found that 56% of eclampsia was potentially preventable through improved ‘patient educationand compliance’, as women who experienced the seizures had symptoms and signs of severe pre-eclampsia (i.e. headaches, visual disturbances and epigastric pain) but did not seek immediatemedical attention.

You et al.64 directly showed, through prospective data collection, that many women, even thoughwell into their pregnancy, had little understanding of the HDP-associated signs and symptoms (e.g.scotoma, abdominal pain) that should cause them to seek care. Similarly, many women did not knowmany of the adverse outcomes with which HDP was associated. These findings, moreover, were seenamong women of both high and low health literacy.

These data would seem to indicate that improvements in access and education would improveoutcomes associated with HDP. One study65 that attempted to assess this possibility occurred inJamaica, where investigators created and distributed a pictorial card illustrating the signs and symp-toms of severe pre-eclampsia that should result in the seeking of care. Women exposed to the card hadsignificant improvements on measures of comprehension concerning appropriate responses to thesigns and symptoms. The frequency of eclampsia within the parish was more than halved comparedwith the 3 years immediately preceding the study, although the numbers were too small to achievestatistical significance.

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Conclusion

The use of benchmarking techniques are invaluable in ascertaining accurate and current disorderincidence data, assessing current practice and affecting positive practice change. In the void of strong,clinical trial data upon which to base treatment strategies in this area, benchmarking techniques areable to provide clinicians, researchers and policy makers with strong data upon which to formulatepractice. Benchmarking also enables us to improve patient safety and lower rates of morbidity, as itprovides the foundation upon which the continuous quality cycle rests. Benchmarking compelsclinicians to strive for better health for patients, by increasing their awareness of the concepts ofcomparison, standard setting and accountability. Benchmarking should be integrated as an extensionof care delivery in all healthcare settings, as it is the only method by which patient safety can beimproved and maintained.

Evidence also suggests that a proportion of HDP-related adverse outcomes are preventable. Thereasons underlying these preventable events suggest several different methods, such as increasedstandardisation of care, simulation, and tools to improve patients’ knowledge, that may help toreduce adverse outcomes. There is some, albeit limited, evidence to support the benefits of thesemethods for HDP, and more study is needed to determine to what extent these methods improvepatient outcomes.

Practice points

� HDP account for significant mortality and morbidity worldwide.� Maternal mortality data is more readily available than morbidity data and ‘near miss’ inci-dents are rarely reported.

� Benchmarking of these disorders is urgently required if we are to decrease mortality andmorbidity for mother and baby.

� Benchmarking techniques can improve outcomes, but reliable and routinely collected dataare required to enable this to occur.

� Patient safety can be improved by methods such as checklists, protocols, simulation,increased patient–carer communication, as well as monitoring and surveillance.

Research agenda

� Strive for an alignment of diagnostic criteria so that clinicians and researchers are all‘speaking the same language’.

� Implement basic reporting of maternal morbidity on an international basis.� Changes in outcomes related to widely disseminated standards for surveillance andmanagement of HDP.

� Determination of the reasons for the racial and ethnic disparity in outcomes that occurs in thesetting of HDP.

� Thorough delineation of the causes for preventable adverse events specifically related to HDP.� Effect on patient outcomes related to simulations specifically focused on HDP.� Differential effect of different types (e.g. high compared with low fidelity simulation) andsettings (e.g. in situ compared with laboratory) for simulation on provider learning andpatient outcomes.

� Assessing whether limited health literacy affects patient understanding of outcomes relatingto HDP.

� Assessment of tools designed to enhance patient knowledge about pre-eclampsia, includingtools relevant for low-health literacy populations.

C. Thornton et al. / Best Practice & Research Clinical Obstetrics and Gynaecology 25 (2011) 509–521520

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