Comparative study between dexmedetomidine-ketamine and fentanyl-ketamine combinations for sedation in patients undergoing extracorporeal shock wave lithotripsy. A randomized double blinded study

Methods
Sixty patients aged between 20 and 50 years, ASA I or II physical status were randomly assigned into two groups. In Group Fentanyl-ketamine (FK) ( = 27): Patients received fentanyl at a 1 μg/kg over 10 min before the procedure and 0.5 mg/kg bolus of ketamine. In Group Dexmedetomidine-ketamine DK ( = 30): patients received dexmedetomidine 1 μg/kg over 10 min before the procedure and a 0.5 mg/kg bolus of ketamine. A blinded researcher assessed the patient’s pain level (primary outcome), sedation level, and awareness via visual analogue scale (VAS), modified Observer’s Assessment Alertness/sedation, and bispectral index respectively.
Results
There was a significant increase in VAS in the recovery period in FK group. There was a significant decrease in hemodynamics (HR, MAP) in the recovery period in DK group. There was a significant increase in bispectral index values in FK group during the postoperative period. The first analgesia required was significantly longer in DK. There was a significant increase in sedation score in the recovery period in FK group. There was no significant difference between the two groups as regards the adverse effects except nausea and vomiting (significant in FK group).
Conclusion
Dexmedetomidine/ketamine combination was accompanied by more prolonged analgesia in the recovery period, prolonged sedation, and delayed request of first dose analgesia with less nausea and vomiting than fentanyl/ketamine combination.