Comparison of the Preemptive/Preventive Effect of Dexmedetomidine and Ketorolac on Post-operative Pain of Appendectomy Patients: A Randomized Clinical Trial.

Objectives: The primary objective was to test the hypothesis that the preemptive/preventive effect of Dexmedetomidine would attenuate the post-operative pain more effectively compared to ketorolac and control groups.

Methods: This study was conducted in Shahid Mohamadi Hospital. Sixty patients undergoing appendectomy operations were randomized in 3 groups. Group A received intravenous Dexmedetomidine bolus (1 μg/kg) and infusion (0.5 μg/kg/h). Group B received slow intravenous bolus ketorolac 30 mg. Group C was the control group. Post-operatively fentanyl (5µg/mL) as patient control analgesia (PCA) was provided only on demand. The primary outcome was the Visual Analogue Scale (VAS) pain scores recorded at 1, 3, 6, 12 and 24 hours postoperatively. The secondary outcome was the 24-hour cumulative fentanyl PCA dose. Tertiary outcomes; changes in blood pressure, heart rate, body temperature, SpO₂ perioperatively. Quaternary outcomes were PONV, shivering.

Results: In the Dexmedetomidine group the mean ± SD pain VAS scores 1.15 ± 1.98 and 0.95 ± 1.76 were significantly lower at 12 and 24 hours after operation (P = 0.004 and P = 0.003) compared to the other two (ketorolac and control) groups. The cumulative volume dose of fentanyl PCA 21.35 ± 11.77 mL was less in the Dexmedetomidine group compared to ketorolac (28.35 ± 9.82 mL, P = 0.629) and control (40.35 ± 12.90 mL, P = 0.003) groups.

Conclusions: Preemptive/preventive effects of Dexmedetomidine were greatest after operation compared to the ketorolac and control groups in the terms of pain scores and amount of analgesia needed postoperatively.