Effect of ketamine and fentanyl in combination with midazolam and propofol during outpatient colonoscopy-a randomised controlled trial

Introduction: There are various methods for sedation in colonoscopy and ketamine has been found to be an effective alternative drug for sedation. Aim: To compare the efficacy and haemodynamic stability of lower dose of ketamine and fentanyl co-administered with midazolam and propofol for colonoscopy. Materials and Methods: Sixty American Society of Anaesthesiologists (ASA) I-II patients undergoing colonoscopy were randomised into two groups. Group I (n=30) (Fentanyl group) was assigned to receive midazolam 20µg/kg, propofol and fentanyl 2µg/kg. Group II (n=30) (Ketamine group) was assigned to receive midazolam 20µg/kg, propofol and ketamine 0.5mg/kg. The parameters measured include haemodynamic stability, recovery, pain scores and endoscopists' satisfaction. All statistical analysis was carried out using Medcalc Statistical Software version 11.0 (Medcalc Software bvba, Belgium). Results: The time to full sedation in the ketamine group was significantly less than that in the fentanyl group (18.3±2.7 seconds Vs 22.4±2.2 seconds). Patients belonging to the ketamine group had a significantly shorter recovery time compared to those in the fentanyl group (5.8±1.4 Vs 8.0±1.9 minutes). Overall patient satisfaction was significantly higher with the use of ketamine. Patients were haemodynamically more stable with a lower incidence of hypotension in ketamine group. Conclusion: The present study shows that midazolam/ketamine/propofol combination provides adequate levels of analgesia and sedation, quicker recovery and has “propofol sparing” effect.