Effects of single-use alfentanil versus propofol on cognitive functions after colonoscopy: A randomized controlled trial

Purpose: Colonoscopy is often accompanied by short-term postoperative cognitive decline. We aimed to explore whether single-use alfentanil for patients undergoing elective colonoscopy could reduce cognitive impairment at discharge compared with propofol.Patients and methods: 172 adult patients undergoing elective colonoscopy were randomized to receive intravenous propofol at 2 mg/kg (group P) or alfentanil at 10 & mu;g/kg (group A); 40 healthy volunteers were included in the blank group. Cognitive function was considered the primary outcome and was measured using five neuropsychological tests before sedation and discharge. The z-score method was used to determine cognitive dysfunction according to z-score >1.96 in two types of neuropsychological tests. Other outcomes included discharge time, vital signs, associated adverse events during colonoscopy, and the satisfaction level of patients and endoscopic physicians.Results: 164 patients (78 in group A and 86 in group P) completed the study protocol. At discharge, the incidence of cognitive dysfunction in group P was 23% and was significantly lower in the alfentanil group (2.5%), with a relative risk of 0.11 (95% confidence interval: 0.03-0.46, P < 0.001). The incidence of hypotension in group A was lower than that in group P (3.8% vs 22.1%, relative risk = 0.17 [95% confidence interval: 0.05-0.46, P = 0.001]), and the discharge time in group A was shorter than that in group P (5 [3-9] vs 13 [10-18] min, P < 0.001).Conclusion: For patients undergoing colonoscopy, single-use alfentanil causes less damage to postoperative cognitive function, less risk of hypotension, and shorter discharge time than propofol.

Automated summary

This study compared the use of single-use alfentanil and propofol in colonoscopy patients and found that single-use alfentanil can reduce the incidence of postoperative cognitive decline, as well as decrease the risk of hypotension and shorten discharge time.