Feasibility of Supervised Trainee Involvement in Colonoscopy without Sedation (CWOS) – Experience at a Single U.S. Training Center

Abstract

Purpose: In the U.S. sedation for colonoscopy is standard practice. Nursing support required for monitoring and recovery; and fixed resources at public institutions such as VA Hospitals appear to have contributed to prolonged wait time. While depicting feasibility in expert hands, recent U.S. publications do not favor trainee involvement in CWOS. Aim: In preparation for a performance improvement program to reduce wait time without incurring additional nursing support, a retrospective feasibility assessment is performed to review cases of CWOS. Methods: We conduct open access education classes for patients referred for outpatient colonoscopy. Patients are given standard instructions including bowel preparation and escort requirement. Inpatients are evaluated by formal consultations. We perform CWOS at patients' request (no escort, concern about side-effects of sedation, wish to see procedure); and at discretion of colonoscopists (sedation risk, e.g. severe COPD). The procedure is performed using standard colonoscope with minimal air insufflation on scope insertion. Abdominal compression and positioning of patient are necessary to facilitate passage of the scope. Polyps are removed on withdrawal of colonoscope. Results: From 2000 to 2006, 8608 colonoscopies were performed. 142 (1.7%) were CWOS. Majority of patients requested CWOS because they did not have escort. After excluding patients with poor bowel preparation (n = 19), the overall cecal intubation rate was (105/123) 85% for CWOS (61 screening and 44 diagnostic), and 44 patients had polypectomy. In addition, CWOS failed in 5 (3.5%) patients because of pain, in 1 with an abdominal hernia and 1 with redundant colon, respectively; and in 11 patients (7.7%) cause of failure was not recorded. There were no immediate CWOS-related cardiorespiratory complications. After excluding patients with poor preparation, success among GI fellows was 17/21 (81%) versus attendings 88/102 (86.3%). On average, fellows took 26 min (14–52) while attendings took 19 min (4–66) to complete the procedure. Conclusions: The current success rate for CWOS is comparable to data in the literature. Poor bowel preparation accounts for substantial (15%) failures. Involvement of supervised trainees in CWOS appears to be feasible with success rates comparable to attending staff. The implication of inclusion of CWOS in the training curriculum and its impact on wait time for colonoscopy in public institutions deserves further prospective studies.