Clinical Gastroenterology and Hepatology 2014;12:785–792

Development of a Program to Train Physician Extenders to PerformTransnasal Esophagoscopy and Screen for Barrett’s Esophagus

Bronia Alashkar,* Ashley L. Faulx,*,‡ Ashley Hepner,‡ Richard Pulice,* Srikrishna Vemana,*Katarina B. Greer,*,‡ Gerard A. Isenberg,*,‡ Yngve Falck–Ytter,* and Amitabh Chak‡

*Section of Gastroenterology, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio; and ‡Division ofGastroenterology and Hepatology, University Hospitals Case Medical Center, Cleveland, Ohio

BACKGROUND & AIMS:

Screening for Barrett’s esophagus (BE) and esophageal adenocarcinoma is not recommendedbecause it was not found to be cost effective. However, physician extenders (PEs) are able toperform unsedated procedures; their involvement might reduce the costs of BE screening. Weexamined the feasibility of training PEs to independently perform transnasal esophagoscopy(TNE) and screen patients for BE and measured their learning curve.

METHODS:

Two PEs at a Veterans Affairs (VA) medical center underwent a structured didactic trainingprogram and observed nasopharyngoscopies before performing TNE under the supervision ofattending endoscopists. Individual technical and cognitive components of TNE were rated on a9-point structured scale. Learning curves were constructed using cumulative summation. Oncethe PEs were judged to be technically competent, each PE performed 10 independent video-taped TNEs, which were graded.

RESULTS:

Both PEs identified anatomic landmarks after 18 consecutive procedures. PE1 and PE2 per-formed satisfactory nasal intubations after 20 and 25 procedures and esophageal intubationsafter 29 and 35 procedures, respectively. They acquired overall competence after supervisedtraining on 43 and 47 procedures, respectively.

CONCLUSIONS:

We developed a program at a VA medical center to train PEs to perform TNE to screen for BE.The PEs were able to perform TNE and recognize esophageal landmarks independently after amodest number of supervised procedures.

Keywords: CUSUM; Esophageal Cancer Screening; Prevention; Cost Reduction.

Abbreviations used in this paper: BE, Barrett’s esophagus; EGD, esoph-agogastroduodenoscopy; GERD, gastroesophageal reflux disease; PE,physician extender; TNE, transnasal esophagoscopy; VA, Veterans Affairs.

© 2014 by the AGA Institute1542-3565/$36.00

http://dx.doi.org/10.1016/j.cgh.2013.10.014

The incidence of esophageal adenocarcinoma hasincreased dramatically in the past several de-

cades.1 Over 9000 cases are now diagnosed annually, andthe majority of these patients die within 5 years of diag-nosis.2 Barrett’s esophagus (BE), a premalignant meta-plastic conditionwith a 0.1% to 0.5%annual estimated riskof progression, is the only known precursor of esophagealadenocarcinoma.3–9 Esophagogastroduodenoscopy (EGD),when performed in a subset of patients with chronicgastroesophageal reflux disease (GERD), diagnoses BE inabout 10% of cases.3,10–12 Subsequent endoscopic sur-veillance of individuals diagnosed with BE is the currentstrategy for early detection of dysplasia/cancer, and non-randomized investigations indicate that surveillance likelyresults in improved survival.13–17 However, because thereis no randomized controlled trial to support its efficacyand EGD is expensive, endoscopic screening for BE is eithernot routinely recommended in all adult patients withchronic GERD or is weakly recommended but only inadult patients with multiple risk factors for esophageal

adenocarcinoma.18,19 Thus, less than 5% of esophagealadenocarcinomas are diagnosed in individuals with previ-ously detected BE.20 Even if endoscopy was recommendedin every adult with GERD symptoms, nearly 40% of ade-nocarcinomas occur in individuals without reflux symp-toms.21,22 Clearly, the challenge is to develop newapproaches for identifying BE that are less expensive thanEGD and can be widely adopted in the population at risk.

The need to use sedation prohibits the performanceof EGD in the primary care setting, adds direct costs(medication administration, monitoring, personnel, andrecovery time), adds indirect costs (day off work forpatients as well as companions to drive patients home),

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and increases adverse events. Transnasal esophagoscopy(TNE) is as sensitive as EGD for identifying BE; is welltolerated; and, when performed, it avoids the costsassociated with sedation.23–25 However, our survey ofgastrointestinal endoscopists found that for a variety ofreasons, including physician reluctance, unsedated TNEhas not been widely accepted in the United States.26

Endoscopic procedures such as TNE offer the prospectof changing our current paradigm of BE screening. In asurvey of primary care physicians, we found that,although the majority replied that they did not recom-mend sedated EGD for chronic GERD symptoms, theavailability of unsedated endoscopy within the primarycare setting would lead to increased screening.27

Up to 25% of asymptomatic male patients older than50 years at Veterans Affairs (VA) medical centers arereported to have BE.28 Thus, the performance of sedatedEGD for BE screening, even if EGD is performed only inpatients with chronic GERD symptoms, at VA medicalcenters with large demand for endoscopic services ischallenging. The aim of this study was to determinewhether it is feasible to train physician extenders (PEs)(ie, nurse practitioners and/or physician assistants) toperform TNE in a VA. Training of PEs could then enable anew model for BE screening in outpatient primary careclinics in VA medical centers.

Patients/Materials and Methods

Setting

This study was performed in the Louis Stokes WadePark VA Medical Center in Cleveland, Ohio within theendoscopy unit and primary outpatient clinics. The studywas approved by the Louis Stokes Wade Park VA MedicalCenter Institutional Review Board.

Training Program

Didactic training: Two PEs (1 physician assistant and1 nurse practitioner) volunteered to learn TNE. Theyunderwent 1 week of didactic structured training,which included four 1-hour lectures on the techniquesof TNE, normal anatomy, and diagnosis of BE and otheresophageal pathology. PEs also read textbook chaptersand reviewed videos on the basic anatomy and pathol-ogy of the oral and nasal cavity, hypopharynx, and theesophagus. This was followed by a 2-week periodobserving nasopharyngoscopy in the ear, nose, andthroat clinic to familiarize trainees with nasopharyngealanatomy.

Procedural training: Hands-on TNE training wasconducted under the supervision of any of 4 attendinggastrointestinal endoscopists in 2 stages. In the initialstage, patients scheduled for standard sedated EGD wereasked permission to perform a TNE while they weresedated. Trainees were instructed on nasal anatomy,

pharyngoesophageal intubation, traversing the esoph-agus, and recognition of the gastroesophageal junctionalanatomy. They were also taught to recognize nasal pas-sages too tight for TNE and when to switch from atransnasal to a peroral approach. After the traineereached a level of competence of performing TNE andidentifying endoscopic landmarks without supervisedinstruction in at least 4 of 5 consecutive cases, they werethen moved to the second stage in which they performedsupervised unsedated TNE on consented volunteersprior to sedation for the standard EGD.

Independent phase: In the final independent phase,once the PEs were considered to have achieved com-petency (score >7 for technical and cognitive compo-nents, see the “Competency Assessment” section below),the trainees performed unsedated TNE in the clinicsetting without supervision, and the entire examinationwas videotaped. TNE examinations in this independentunsupervised phase were performed for screening;unlike the training phase, these screened subjects didnot have follow-up EGD unless suspected BE wasidentified during TNE. These procedures were notscored for the components of competency. The first 10consecutive cases that the PEs performed without su-pervision were reviewed by an independent supervisingphysician (AC) who was blinded to the findings for ac-curacy of interpretation and completeness of theexamination.

Transnasal Esophagoscopy Protocol

Patients with a history of recurrent epistaxis, alterednasopharyngeal anatomy, allergy to lidocaine derivatives,bleeding diathesis, or prolonged prothrombin timewere excluded. TNE was performed with the TNE-5000esophagoscope available from Vision Sciences, Inc(Orangeburg, NY). This system has a disposable outersheath that completely covers the endoscope. It also hasa disposable channel for biopsies. The sheath allowssterile office-based endoscopy without the need todisinfect the inner endoscope; therefore, screening canbe performed within the primary care clinic. UnsedatedTNE was performed in the sitting position. The nasalpassage with the wider patency was selected and anes-thetized with an atomizer using a 1:1 mixture of 2.0%lidocaine and 1.0% neosynephrine instilled deep into theselected nares over a 2-minute period. A 3-secondinstillation of aerosolized 14% benzocaine into theoropharynx just prior to intubation was also used insome patients. Again, trainees were instructed to switchfrom a transnasal to peroral approach when the naso-pharynx was too tight. Subjects who underwent TNEduring the independent phase and were found to havesuspected BE did not have a biopsy attempted and werereferred for standard sedated EGD. Biopsies were notperformed because PEs often do not have privileges toperform biopsies.

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Competency Assessment

Learning curves are based on defining objectivethresholds of competency. Endoscopic learning can bebroken into 2 components: technical competence andcognitive competence. The technical performance of TNErequires the passage of the scope through the naso-pharynx and intubation of the esophagus. For TNE pro-cedures, the supervising physician scored the trainees’technical proficiency (Figure 1) in passing the endoscopethrough the nasopharynx and intubating the esophagususing a defined Likert scale of 1 to 9 (1 ¼ novice and9 ¼ expert skill) after each procedure that the PE per-formed in the supervised training phase. We also moni-tored the frequency with which TNE was converted fromthe transnasal to peroral route. A rate less than 10%was considered acceptable. Technical competence wasdefined as a score of �7 for intubating the nasopharynxand intubating the esophagus in 90% of procedures. Acompetency threshold of 90% was selected based onstudies of endoscopic learning, including a study weperformed in colonoscopy learning and the AmericanSociety of Gastrointestinal Endoscopy’s definitions ofcompetence for basic endoscopic procedures.29–32 Thecognitive learning process for TNE consists of identifyingspecific landmarks that define the endoscopic presenceof BE. These landmarks include the squamocolumnarjunction, the top of the gastric folds, and the diaphrag-matic pinch. The supervising physician noted whetherthe PE trainee was able to accurately identify eachlandmark with or without supervision (Figure 1). Cog-nitive competency was defined as the ability to identifyeach landmark without supervision (score of �7). Thesupervising physician evaluator also rated the overallperformance of TNE by the trainee, with a score of �7considered to be the threshold of competency.

Analysis

The trainees’ technical learning curves for TNE werecalculated in consecutive blocks of 5 procedures usingthe cumulative sum (CUSUM) method. One-way varianceanalysis was used to compare success rates for suc-cessful intubation between consecutive blocks of 5 pro-cedures. The trainees’ cognitive learning curves werecalculated using the same scoring system. Again, cogni-tive learning was calculated in blocks of 5 procedures,and 1-way variance was used to compare successfulidentification of all landmarks between consecutiveblocks of 10 procedures.

Results

Overall Competence

Trainers judged that PE1 and PE2 were able toperform independent TNE procedures and had achieved

overall cognitive and technical competence after 44and 47 supervised procedures, respectively (Figure 2).PE1 could not complete 1 procedure and PE2 couldnot complete 6 procedures during their supervisedtraining. All PE1 procedures were performed trans-nasally, whereas 3 PE2 procedures were changed from atransnasal to peroral route. Following the supervisedtraining procedures, both PEs performed 10 independentunsupervised procedures. All procedures were video-taped and reviewed by an attending gastroenterologistwho confirmed the findings documented by the PEs.

Cognitive Competence

Both PEs were able to satisfactorily identify anatomiclandmarks including the gastroesophageal junction, thediaphragm, and the top of the gastric folds after 18consecutive procedures performed on sedated patients(Table 1). Each trainee completed 10 TNE procedures inthe unsupervised independent phase of the study. Theseprocedures were videotaped and reviewed subsequentlyby an attending physician (AC). Both PE trainees wereaccurately able to identify anatomic landmarks inde-pendently. In addition, the trainees made a diagnosis ofsuspected BE in 1, hiatal hernia in 3, and esophagitis in 6of these cases. These diagnoses were confirmed uponreview of the videotaped examinations. The Z line wascompletely visualized in 18 cases and partially visualizedin 2 cases. Two individuals, 1 with severe esophagitisand 1 with suspected BE, were referred for subsequentEGD.

Technical Competence

Nasal intubation and esophageal intubation were the2 maneuvers that were technically most challengingwhen performing TNE. Intubation of the nasal cavity waslearned more easily than intubation of the esophagus.PE1 performed nasal intubation satisfactorily after 20supervised TNE procedures, and PE2 performed nasalintubation satisfactorily after 25 supervised TNE pro-cedures (Figure 3). PE1 had to perform 29 supervisedTNE procedures before satisfactory performance ofesophageal intubation, and PE2 had to perform 35 su-pervised TNE procedures before satisfactory perfor-mance of esophageal intubation (Figure 4). The PEtrainees each performed and completed 10 independentunsupervised procedures on unsedated study subjects.Aside from one episode of minor epistaxis, which ceasedspontaneously, there were no adverse events. The studysubjects rated pain, gagging, and choking on a 9-pointLikert scale (1 ¼ minimal and 9 ¼ severe). The medianscores reported by patients after undergoing these pro-cedures were 1 for each symptom. Sixteen, 17, and 17subjects rated pain, gagging, and choking at a score of 3or less, respectively.

Figure 1. TNE procedure evalua-tion form.

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Figure 3. Learning curve assessing competence in nasalintubation.

Figure 2. Learning curves assessing overall competence inperforming TNE.

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Discussion

In order to propose screening for BE, the challenge isclearly to develop an approach that is less costly andsafer than EGD. We chose to perform this study in theWade Park VA Medical Center endoscopy suite and pri-mary care clinic because this predominantly adult malepopulation is at an increased risk for BE. The training ofnonphysicians to perform TNE would also address thephysician shortage within the VA medical system. Wechose to train PEs (ie, nurse practitioners and/orphysician assistants) in the performance of TNE, a novelmodality that is less expensive and invasive than stan-dard EGD. The goal of this study was simply to determinewhether PEs could be trained to perform TNE and definethe training process required to achieve technical com-petency as well as cognitive competency in recognizingesophageal landmarks and BE.

The primary objective of our study was to determinethe feasibility of training PEs to perform screening TNEexaminations in a VA. We considered training primarycare physicians but felt it would be more cost effective totrain PEs. Given the time line and number of upperendoscopies performed in our VA and the ability to getconsent from subjects undergoing EGD, we found wewere easily able to train 2 PEs who had other clinicalresponsibilities over the course of 6 to 9 months,supervising each PE for 1 to 2 half days during a week.Our study demonstrates it may be feasible to consider anew model of screening for BE in VA hospitals. The use of

Table 1. Number of Successive Procedures Completed perPE to Demonstrate Competency in Specific Skills

Skill acquired PE1 PE2

Identify landmarksa 18 18Nasal and oral cavity intubation 20 25Esophageal intubation 29 35Perform TNE independently 43 47

aLandmarks relevant to a procedural skill include identification of gastro-esophageal junction, hiatal hernia, and gastric folds.

unsedated TNE performed by PEs could not only reducesome of the demand for sedated EGD plus the cost ofendoscopy, it would enable BE screening in a primarycare setting, thus reaching a greater population of vet-erans who are at risk. The subjects identified with sus-pected BE could then be referred to gastrointestinalendoscopists for confirmation of BE by standard EGD,and those with BE could be enrolled in surveillanceprograms.

There is a clear precedent for nurses performingscreening and surveillance endoscopy procedures.Although nurses in the United States do not perform colo-noscopies, other countries, such as the United Kingdom,have implemented nurse colonoscopy to decrease the costof screening programs.33–35 Nurses have also been trainedto perform unsedated screening procedures, such as flex-ible sigmoidoscopy.36 Therefore, it is natural to extend theconcept of nurse performance of screening endoscopy to anew unsedated procedure such as TNE. This study dem-onstrates that the training of nonphysicians in TNE can beperformed within a structured training program.

Measurement of learning is a subjective process.Using an objectively defined scale of competency, wemade the assessment as quantitative as possible. Thethreshold of 90% accuracy compared with supervisorinterpretation was based on our own study on acquiringendoscopic skills as well as in other studies of

Figure 4. Learning curves assessing competence in esoph-ageal intubation.

790 Alashkar et al Clinical Gastroenterology and Hepatology Vol. 12, No. 5

endoscopic learning. Cognitive skills for recognizingesophageal landmarks were attained fairly readily. Thistraining was sufficient to recognize esophagitis, hiatalhernias, and BE and to perform a screening examina-tion. However, this training was not sufficient torecognize or manage more complex esophageal disor-ders. Thus, we would not expect the PEs to be compe-tent, and we would not recommend PE-performed TNEin patients suspected to have a subtle condition such aseosinophilic esophagitis. Both PEs who volunteered fortraining had gastroenterology experience, so they werefamiliar with esophageal diseases and BE. The presentresearch was not able to determine whether there isany difference in learning between PEs who work ininternal medicine compared with those who work ingastroenterology or even to determine the variation inlearning among PEs. One would have to train a farlarger sample size to determine what factors areimportant for learning. The aim of this study was simplyto demonstrate the feasibility of training PEs for BEscreening.

The technical skills required to perform TNE tooklonger to attain than the cognitive skills required forrecognizing esophageal landmarks. Esophageal intuba-tion was more difficult to master than nasal intubation.Both of these skills and other technical aspects of per-forming TNE were satisfactorily and safely learned byboth nonphysicians within 50 supervised procedures.Following technical learning, the PEs were safely able toperform unsedated TNE procedures for screening. Thesubjects who underwent the TNE procedures toleratedthese procedures and did not report much greaterdiscomfort than when TNE was performed by trainedgastroenterologists.

The study was performed at a VA medical center, andthe results may not be representative of a more generalpopulation. TNE might prove more challenging in ayounger population or a population with a greater pro-portion of women. However, the VA population doesrepresent a population at an increased risk for BE and isan appropriate population to develop a screening pro-gram.28 Certain VA medical centers, such as the one inwhich this study was performed, have had to outsourceendoscopic procedures because of a high demand forendoscopic services. The performance of TNE by non-physicians may help to meet some of this demand.

The objective of the study was to train PEs to examinethe distal esophagus specifically so they would be able torecognize BE. They were not trained in other aspects ofesophageal diseases. Independent TNE examinations thatthe PEs performed in this study and are currently per-forming are restricted to patients with GERD withoutalarm symptoms. In most states, PEs need to practiceunder the supervision of a physician. The ability to vid-eotape the TNE examinations for subsequent reviewallowed the attending physicians to ensure that the 20independent examinations performed by the PEs wereadequate and confirm the endoscopic diagnosis made by

the PEs. Conceivably, in clinical practice, all nonphysicianTNE examinations could be videotaped and the adequacyof the examination confirmed by the supervisingphysician.

The results of this study should be interpreted withinthe limitations of the study design and the aim of thestudy. Training was limited to one nurse practitionerand one physician assistant who volunteered to learnTNE at a VA. These trainees were clearly motivated tolearn TNE and had previous training in gastrointestinaldiseases. PEs without specific training may require a lotmore training, and it is possible that some will not beable to learn TNE. The small sample size limits general-izing these findings. The purpose of this study was sim-ply to determine whether PEs could be trained toperform screening TNE. Although the grading scale forassessing the supervised phase of training was quanti-tative, the interobserver agreement between the 4graders could not be assessed. This study only assessed10 independent TNE procedures for each PE, so it cannotdetermine whether these PEs will be able to detect BEwith the same sensitivity as gastroenterologists. Wemeasured cognitive competency in identifying anatomicesophageal landmarks. However, other studies that haveexamined nurse performance of endoscopic proceduresin clinical practice have found that nurses may actuallyperform a more careful inspection than physicians.37–39

Therefore, it is reasonable to assume that nurse practi-tioners or physician assistants who perform TNEscreening will perform a careful inspection of theesophagus for evidence of BE.

The cost of sedated EGD and accessibility have been 2barriers to recommending screening for BE. This studysuggests that it is feasible to propose a less expensivestrategy for BE screening—performance of unsedatedTNE by nonphysicians. Two trainees were able to masterthe skills of TNE and one is currently performing thisunsedated procedure on patients seen in primary careclinics at the Cleveland Wade Park VA as part of a new BEscreening program. Larger prospective studies will berequired to determine whether trained PEs can effectivelyidentify BE in such a screening program and whetherscreening will ultimately impact the early detection ofesophageal adenocarcinoma. Despite numerous studiesdemonstrating that unsedated TNE is quite well tolerated,there are clearly other obstacles to acceptance of unse-dated endoscopy, such as physician and patient atti-tudes.26 The performance of TNE procedures by nursepractitioners or physician assistants in an office settingcould also help change the perception of primary carephysicians and patients.

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Reprint requestsAddress requests for reprints to: Amitabh Chak, MD, Wearn 247, UniversityHospitals of Cleveland, 11100 Euclid Avenue, Cleveland, Ohio 44106. e-mail:axc22@cwru.edu; fax: (216) 983-0347.

Conflicts of interestThe authors disclose no conflicts.

FundingThis work was supported by the US Public Health Service research grants RC4DK090645 from the National Institute of Diabetes and Digestive and KidneyDiseases and U54 CA163060 and P50 CA150964 from the National CancerInstitute.