Patient-controlled sedation versus intravenous sedation for colonoscopy in elderly patients: a prospective randomized controlled trial.

Background: A prospective randomized trial was conducted to compare the safety, effectiveness, and patient acceptance of patient-controlled sedation and intravenous sedation for colonoscopy in a group of elderly patients undergoing outpatient colonoscopy.

Methods: One hundred patients over 65 years of age were recruited and randomized to patient-controlled sedation (n = 50) or intravenous sedation (n = 50) groups by means of computer-generated numbers. In the patient-controlled sedation group, a mixture of propofol and alfentanil was delivered by means of a patient-controlled 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. In the intravenous sedation group, fixed doses of diazemuls (0.1 mg/kg) and meperidine (0.5 mg/kg) were given with further increases in dosages administered at the discretion of the endoscopist. Outcome measures assessed included cardiopulmonary complications, recovery time, pain score, and satisfaction score.

Results: The mean (SD) age of patients in the patient-controlled sedation and intravenous sedation groups were, respectively, 72.4 years (5.3) and 73.5 years (6.1). The mean dose of propofol consumed in the patient-controlled sedation group was 0.79 (0.46) mg/kg. The mean doses of diazemuls and meperidine consumed in intravenous sedation group were, respectively, 5.8 (1.3) mg and 30.1 (6.8) mg. Hypotension occurred in 2 (4%) patients in the patient-controlled sedation group and 14 (28%) in the intravenous sedation group (p < 0.01). Oxygen desaturation was recorded for 4 patients (8%) in the intravenous sedation group. The median (interquartile range [IQR]) recovery time was significantly shorter in the patient-controlled sedation group compared with the intravenous sedation group (respectively, 0 minutes [IQR 0-5] vs. 5 minutes [IQR 5-10]; p < 0.01). There were no statistically significant differences between groups for pain and satisfaction scores.

Conclusions: Patient-controlled sedation appears to be safer than intravenous sedation, with comparable effectiveness and acceptance, in elderly patients undergoing elective outpatient colonoscopy.