Tolerance and safety to colonoscopy with conscious sedation in Malaysian adults

Tolerance to colonoscopy varies between populations and data from the South East Asian region is lacking. We aimed to determine tolerance and safety with to colonoscopy; conscious sedation and identify risk factors for complications in Malaysian adults. Consecutive outpatients undergoing colonoscopy were enrolled prospectively. A combination of pethidine and midazolam were used and tolerance to colonoscopy assessed three hours post-procedure using a validated scale. All patients were monitored for cardiorespiratory depression and risk factors for complications were identified. Two hundred and eight patients (mean age 57.2 +/- 14.8 years, 48% female) were enrolled. The population ethnicity consisted of 45 (21.63%) Malays, 101 (48.56%) Chinese and 56 (26.92%) Indians. Conscious sedation was achieved with 5.0 +/- 1.1 mg of midazolam and 43.3 +/- 14.0 mg of pethidine. Thirty (14.4%) patients tolerated the procedure poorly and independent predictors included female gender (OR 2.93, 95% CI = 1.22 to 7.01) and a prolonged duration of procedure (OR 2.85, 95% CI = 1.08 to 7.48). Hypotension occurred in 13 (6.25%) patients, with age > 65 years as the only risk factor (OR 13.17, 95% CI = 1.28 to 137.92). A prolonged duration was the main cause of hypoxia (OR 5.49, 95% CI = 1.54 to 19.49), which occurred in 6 (2.88%) patients. No major complications occurred during the study period. The current practice of conscious sedation is safe and tolerated well by most adults in our population. However, poor tolerance in a notable minority may have significant clinical implications.