Nurse-administered propofol-alfentanil sedation using a patient-controlled analgesia pump compared with opioid-benzodiazepine sedation for outpatient colonoscopy

Background and study aim: Nurse-administered propofol sedation (NAPS) and patient-controlled sedation using patient-controlled analgesia (PCA) pumps are gaining increasing popularity for gastrointestinal endoscopy. We compared the safety and efficacy of NAPS using PCA pumps with diazemuls-pethidine sedation (DIPS) for outpatient colonoscopy. Patients and methods: In a prospective randomized controlled trial patients underwent outpatient colonoscopy with sedation by either NAPS or DPS. For NAPS, following intravenous loading of 0.8 mg/kg propofol, mixtures of 14.3 mg propofol and 35 microgram alfentanil were titrated by nurses using a PCA pump. For DPS, 0.1 mg/kg diazemuls and 0.5 mg/kg pethidine were given as intravenous bolus; further titration was administered as half doses at the endoscopist's discretion. Adequacy of sedation was measured by the Observer's Scale for Sedation and Alertness (OSSA) score (range 1-5). Results: Between July 2005 and June 2006, 88 patients were randomly allocated to NAPS and 90 to DPS. The groups were comparable for baseline characteristics and procedure time. With NAPS, levels of sedation both during colonoscopic intubation and at reaching the cecum were significantly deeper than with DPS (OSSA 3 vs. 5, P < 0.0001). There were no significant differences in cardiopulmonary complication rates, pain scores, satisfaction scores, and patients' willingness to repeat colonoscopy with the same sedation. Drugs cost for NAPS was higher than for DPS (Hong Kong dollars [HKD] 98.34 vs. 5.01). Conclusion: Despite higher costs, nurse-administered propofol-alfentanil sedation using a PCA pump can provide deeper conscious sedation, comparable satisfaction, and similar complication risks compared with conventional opioid-benzodiazepine sedation.