Objective: Prevention and treatment of postoperative pain and operation complications such as nausea and vomiting are most important concerns in postoperative care. There are several mechanisms involved in postoperative pain. Gabapentin is a gamma aminobutyric acid analogue that is known as an anticonvulsant drug. This drug is tolerated well and has known effects on pain and anxiety. This study has compared the effect of gabapentin on postoperative pain, operation complications and haemodynamics.
Subjects and Methods: This randomized double blinded placebo controlled clinical trial was conducted on 61 patients divided randomly into two groups (30 as cases and 31 as controls). All patients had total abdominal hysterectomy. In the first group, the patients got 100 mg gabapentin in the night and 300 mg gabapentin orally (one capsule) two hours before surgery. The second group got one capsule of multivitamin orally. Then all patients were subjected to the same anaesthesia protocol and total abdominal hysterectomy. During the 24 hours after operation, the patients were assessed according to pain, nausea, vomiting, dizziness, systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse rate (PR) and morphine use at 1, 6, 12 and 24 hours.
Results: Mean age and weight of patients were 45.86 ± 4.06, 48.16 ± 4.48, 64.56 ± 13.29 and 68.8 ±12.88 in the study population and control groups, respectively. Except in the first hour after operation (p = 0.02), there was no significant differences between the two groups in morphine use. There was no significant correlation between the groups according to postoperative complications and the haemodynamic parameters (PR, SBP and DBP).
Conclusion: Results show that gabapentin can decrease the need for morphine use in the first hour after operation only and has no significant effect on operation complications. Thus, we suggest gabapentin for pain management, and not to decrease opium use.