Dexmedetomidine versus fentanyl as adjuvant to propofol: comparative study in children undergoing extracorporeal shock wave lithotripsy.

BACKGROUND the present study was designed to compare the efficacy, tolerability and safety of dexmedetomidine and fentanyl when combined with propofol during extracorporeal shock wave lithotripsy in children. METHODS fifty children aged 3-8 years, the American Society of Anesthesiologists status I and II, scheduled for elective extracorporeal shock wave lithotripsy were randomly allocated to receive a loading dose 0.7 μg kg over 10 min followed by maintenance infusion 0.3 μg kg h of either dexmedetomidine in propofol/dexmedetomidine group or fentanyl in propofol/fentanyl group (n = 25 each). The target drug infusion rates were adjusted to keep the haemodynamics within ± 20% from the baseline values. All patients received propofol infusion to maintain bispectral index values (40-60) throughout the procedure. Induction and maintenance doses of propofol were recorded. Total doses of both studied drugs were calculated. Perioperative haemodynamics, incidence of intraprocedural and postprocedural complications and time to first analgesic requirement were recorded. RESULTS the propofol requirement was significantly lower in the propofol/dexmedetomidine group than that in propofol/fentanyl group during induction and maintenance of anaesthesia (P < 0.0001). Total doses of fentanyl and dexmedetomidine were 0.961 (0.1) μg kg and 0.925 (0.07) μg kg, respectively. Mean arterial pressure and heart rate were significantly decreased compared to the baseline throughout the procedure in both groups and increased significantly relative to both baseline and the other group at 30 min in the propofol/fentanyl group and 60 min in the propofol/dexmedetomidine group in the recovery area (P < 0.05). In propofol/dexmedetomidine group, the incidence of intraprocedural hypoventilation was significantly lower (P = 0.016) and time to first analgesic requirement was significantly longer (P < 0.0001) than that in propofol/fentanyl group. CONCLUSION both propofol/fentanyl and propofol/dexmedetomidine combinations at mentioned dose regimen were effective and well tolerated for children undergoing extracorporeal shock wave lithotripsy. However, propofol/dexmedetomidine combination was accompanied with less propofol consumption, prolonged analgesia and lower incidence of intraprocedural and postprocedural complications.