Montazeri K, Kashefi P, Honarmand A
Correspondence: Dr Azim Honarmand, honarmand@med.mui.ac.ir
ABSTRACT
Introduction Gabapentin has demonstrated analgesic effects in clinical trials as a preemptive analgesic and in acute postoperative pain management. This study was conducted to evaluate whether the pre-emptive use of gabapentin could reduce postoperative pain and morphine consumption in patients after lower extremity orthopaedic surgery.
Methods 70 ASA I and II patients were randomly assigned to receive 300 mg gabapentin or placebo in a double-blind manner two hours before surgery under general anaesthesia. Postoperatively, the pain was assessed on a visual analogue scale (VAS) at 2, 4, 12, and 24 hours at rest. Morphine 0.05 mg/kg intravenously was used to treat postoperative pain on patients' demand. Total morphine consumption in the first 24 hours after surgery was also recorded.
Results Patients in the gabapentin group had significantly lower VAS scores at all time intervals of 2, 4, 12, and 24 hours, than those in the placebo group (respectively, 55.50 [mean] +/- 15.80 [standard deviation], 57.30 +/- 19.30, 45.74 +/- 16.00, 44.60 +/- 17.64, versus 72.30 +/- 14.00, 70.50 +/- 18.13, 62.00 +/- 23.32, 66.50 +/- 25.70; p-value is less than 0.05). The total morphine consumed after surgery in the first 24 hours in the gabapentin group (15.43 +/- 2.54) was significantly less than in the placebo group (17.94 +/- 3.00; p-value is less than 0.05).
Conclusion Pre-emptive use of gabapentin 300 mg orally significantly decreases postoperative pain and rescue analgesic requirements in patients who undergo lower extremity orthopaedic surgery.
Keywords: analgesic requirement, gabapentin, morphine demand, orthopaedic procedures, pain management, postoperative pain
Singapore Med J 2007; 48(8): 748–751