A comparison of different proportions of a ketamine-propofol mixture administered in a single injection for patients undergoing colonoscopy.

Introduction: In this study, we aimed to determine the appropriate proportion of ketamine-propofol (ketofol), which was prepared in two different proportions for colonoscopy procedures.

Material And Methods: This is a prospective and randomized trial. Group 1 was administered a mixture of 100 mg ketamine and 200 mg propofol. Group 2 was administered 50 mg ketamine and 200 mg propofol. Additional doses of 0.5 mg/kg bolus propofol without ketamine were administered to both groups to stabilize the bispectral index at 70-80 and with a Ramsey sedation score of 3-4. The pulse rate, mean arterial pressure (MAP), peripheral oxygen saturation values, colonoscopy period, adverse events, recovery time, discharge time, additional propofol doses, total propofol doses, colonoscopist and patient satisfaction were recorded.

Results: In group 2, the 1 min MAP mean was significantly lower than the initial, 10, 15 and 20 min MAP means (p = 0.014, p = 0.002). The 20 min PR mean of group 2 was statistically significantly higher than group 1 (p = 0.045). The 15 min PR mean of group 2 was significantly lower than the initial and the 1 min PR means (p = 0.023, p = 0.006). The total propofol dose mean of group 2 was significantly higher than group 1 (p = 0.0001). The presence of adverse events in group 2 was significantly lower than that in group 1 (p = 0.0001). The mean colonoscopist satisfaction in group 2 was significantly lower than that in group 1 (p = 0.047).

Conclusions: In colonoscopy, a ketofol mixture prepared in the proportion 1 : 2 provides appropriate hemodynamic conditions and sufficient sedation.