Fentanyl or tramadol, with midazolam, for outpatient colonoscopy: analgesia, sedation, and safety.

The present study determined the acceptability of colonoscopy in outpatients treated with tramadol or fentanyl for analgesia and sedation. One hundred fifty patients were randomly assigned to receive midazolam, 0.05 mg/kg, and fentanyl, 2 microg/kg, intravenously (group 1), midazolam, 0.05 mg/kg, and tramadol, 1 mg/kg, per os (group 2), or midazolam, 0.05 mg/kg, and tramadol, 2 mg/kg, per os (group 3). Pain severity, level of sedation, cardiorespiratory parameters, and procedure-related side effects and complications were registered and analyzed. No significant cardiorespiratory disturbances were observed. Sedation level during the procedure was similar in all groups. Pain severity values measured during the procedure was significantly higher in groups 2 and 3 than in group 1 (P < 0.001). Both hospital and home adverse events occurred more frequently in groups 2 and 3 compared to group 1 (P < 0.03). The patients receiving fentanyl-based analgesia tolerated colonoscopy better than patients treated with tramadol.