Premedication with Gabapentin: The Effect on Tourniquet Pain and Quality of Intravenous Regional Anesthesia

Abstract

Gabapentin, an oral non-opioid analgesic, has been used to decrease pain after a variety of surgical procedures. We hypothesized that premedication with gabapentin would minimize tourniquet-related pain in patients receiving IV regional anesthesia (IVRA). Patients undergoing elective hand surgery with IVRA were randomly assigned to one of two study groups using a double-blind study design. The control group (n = 20) received placebo capsules 1 h before the surgery, and the gabapentin group (n = 20) received gabapentin 1.2 g p.o. before the operation. IVRA was achieved in all patients with lidocaine, 3 mg/kg, diluted with saline to a total volume of 40 mL. Fentanyl, 0.5 microg/kg IV, was administered as a rescue analgesic during surgery. Sensory and motor block onset and recovery times, tourniquet pain, and quality of anesthesia were assessed at specific time intervals during the perioperative period. Visual analog scale pain scores (0-10) were recorded during the 24 h follow-up period, and patients received diclofenac, 75 mg IM, if their pain score was >4. The onset of the sensory and motor block did not differ between the two study groups. However, tourniquet pain scores at 30, 40, 50, and 60 min after cuff inflation were lower in the gabapentin group (P < 0.05). The time to intraoperative analgesic rescue was prolonged in the gabapentin group (35 +/- 10 min vs 21 +/- 13 min, P < 0.05), and less supplemental fentanyl was required (35 +/- 47 microg vs 83 +/- 73 microg, P < 0.05). The quality of anesthesia, as independently assessed by the anesthesiologist and the surgeon, was significantly better in the gabapentin (versus control) group. In the gabapentin group, the time to requesting a rescue analgesic after surgery was prolonged (135 +/- 25 min vs 85 +/- 19 min, P < 0.05), and postoperative pain scores at 60 min (3.8 +/- 0.9 vs 2.2 +/- 0.5) and 120 min (3.2 +/- 1.4 vs 1.8 +/- 0.8), as well as diclofenac consumption (30 +/- 38 mg vs 60 +/- 63 mg), were reduced after surgery. Premedication with oral gabapentin (1.2 g) decreased tourniquet-related pain and improved the quality of anesthesia during hand surgery under IVRA. Gabapentin also reduced pain scores in the early postoperative period.