Sedation, analgesia, and cardiorespiratory function in colonoscopy using midazolam combined with fentanyl or propofol

The use of sedatives during colonoscopy remains controversial because of its safety concerns. We compared cardiorespiratory function and sedative and analgesic effects in sedative colonoscopy, using combinations of midazolam with either fentanyl or propofol.

Eligible patients (n = 480) received 1.0-2.0 mg midazolam alone (n = 160), midazolam combined with either 50-100 mg fentanyl intramuscularly (n = 160), or 0.5-2.5 mg/kg propofol intravenously, as premedication for sedative colonoscopy. Pulse rate, blood pressure, and saturation of peripheral oxygen (SpO(2)) were monitored. Levels of sedation and analgesia were semi-quantitatively scored using visual analog scales, and amnesia profiles were qualitatively evaluated.

Combining midazolam with either fentanyl or propofol resulted in acceptable sedative and analgesic effects compared to treatment with midazolam alone (P < 0.001), with the combination with propofol giving more favorable results. More patients receiving the propofol combination became amnestic to the procedure than patients receiving the fentanyl combination. However, midazolam combined with propofol disturbed the pulse rate (P < 0.05) and blood pressure (P < 0.001) more significantly than a combination with fentanyl, or midazolam alone.

The combination of midazolam with either fentanyl or propofol allowed patients to undergo colonoscopy under comparable sedative and analgesic conditions. The combination with fentanyl had a significantly lower effect on pulse rate and blood pressure. The combination with propofol produced superior amnestic effects.