ABSTRACT
OBJECTIVE: To assess the safety, feasibility, and acceptability of patient-controlled sedation for elective day-case colonoscopy, and the factors predicting patients' unwillingness to use patient-controlled sedation for colonoscopy. DESIGN: Prospective, non-randomised study. SETTING: University-affiliated endoscopy centre, Hong Kong. PARTICIPANTS: Five hundred patients who underwent elective day-case colonoscopy were prospectively recruited from January 2001 to June 2002. INTERVENTION: Sedation for colonoscopy was a mixture of propofol and alfentanil, which was delivered by means of a patient-controlled syringe pump. Each bolus delivered 4.8 mg propofol and 12 microg alfentanil. No loading dose was used and the lockout time was set at zero. MAIN OUTCOME MEASURES: Cardiopulmonary complications, dose of patient-controlled sedation used, recovery time, satisfaction score, delayed side-effects, and the willingness to use the same sedation protocol for future colonoscopy. A multiple stepwise logistic regression model was used to assess which factors might predict unwillingness to use patient-controlled sedation for colonoscopy. RESULTS: The mean (standard deviation) age of patients was 53.0 (13.9) years. The mean dose of propofol consumed was 0.93 (0.69) mg/kg. Forty-three (8.6%) patients developed hypotension during the procedure. The mean satisfaction score was 7.2 (2.6). Sixteen (3.2%) patients developed delayed side-effects. The median (interquartile range) recovery time was 0 (0-5) minutes. Approximately 78% of patients were willing to use patient-controlled sedation for future colonoscopy if needed. Younger age (<50 years), female sex, a higher mean dose of sedatives used, a lower satisfaction score, and the presence of delayed side-effects were independent factors that were associated with patients' unwillingness to use patient-controlled sedation for colonoscopy. CONCLUSION: . The use of patient-controlled sedation for elective colonoscopy is safe, feasible, and acceptable to most patients.
