Is "really conscious" sedation with solely an opioid an alternative to every day used sedation regimes for colonoscopies in a teaching hospital? Midazolam/fentanyl, propofol/alfentanil, or alfentanil only for colonoscopy: a randomized trial

We investigated the satisfaction of patients and endoscopists and concurrently safety aspects of an "alfentanil only" and two clinically routinely used sedation regimes in patients undergoing colonoscopy in a teaching hospital. One hundred and eighty patients were prospectively randomized in three groups: M (midazolam/fentanyl), A (alfentanil), and P (propofol/alfentanil); M and A were administered by an endoscopy nurse, P by an anesthesia nurse. Interventions, heart rate, saturation, electrocardiogram, noninvasive blood pressure, and expiratory CO₂ were monitored using video assistance. After endoscopy, patients and gastroenterologists completed questionnaires about satisfaction. A high level of satisfaction was found in all groups, with patients in group P being more satisfied with their sedation experience (median 1.75, p < 0.001). Gastroenterologist satisfaction varied not significantly between the three alternatives. Patients in group A felt less drowsy, could communicate more rapidly than patients in both other groups, and met discharge criteria immediately after the end of the procedure. Respiratory events associated with sedation were observed in 43% patients in group M, 47% in group P, but only 13% in group A (p < 0.001). These results suggest that alfentanil could be an alternative for sedation in colonoscopy even in the setting of a teaching hospital. It results in satisfied patients easily taking up information, and recovering rapidly. Although one might expect to observe more respiratory depression with an "opioid only" sedation technique without involvement of anesthesia partners, respiratory events were less frequent than when other methods were used