The Efficacy of Preoperative Gabapentin in Spinal Surgery: A Meta-Analysis of Randomized Controlled Trials

Background: Pain management after spinal surgery has been studied for years. Gabapentin is a third-generation antiepileptic drug that selectively affects the nociceptive process and has been used for pain relief after surgery. However, the relationship between gabapentin and postoperative pain in spinal surgery is still controversial. Objective: To assess the efficacy of the pre-emptive use of gabapentin in spinal surgery. Study Design: A meta-analysis of randomized controlled studies. Setting: The MEDLINE, EMBASE, ClinicalTrials.gov, and Web of Science databases were systematically searched. Methods: This meta-analysis of randomized controlled trials (RCTs) was performed to compare the use of gabapentin with placebo in spinal surgery regarding to the following: the mean difference (MD) of postoperative opioid requirements, the changes of visual analog scale (VAS) scores in 2 groups, and the incidence rate of adverse effects. An electronic-based search of all related literatures was conducted, and only RCTs for spinal surgery were included. The MD of postoperative opioid requirements and VAS scores and the relative risk (RR) of the incidence rate of adverse effects in the gabapentin group versus the placebo group were extracted throughout the study. Results: Ten trials, involving 827 patients, met the inclusion criteria and were included in this meta-analysis. The total morphine consumption was significantly lower over the first 24 hours postoperatively in the gabapentin group (P < 0.05). The VAS scores at 2, 4, 6, 12, and 24 hours were less in the gabapentin group (P < 0.05). The incidence rate of vomiting, pruritus, and urinary retention was significantly less in the gabapentin groups (RR = 0.53, 95% CI 0.32-0.86, P < 0.05; RR = 0.38, 95% CI 0.22-0.66, P < 0.05; RR = 0.57, 95% CI 0.34-0.98, P < 0.05, respectively). Limitations: All of the studies we screened were published online except for unpublished articles. Only 10 RCTs met our inclusion criteria, so the sample size was still relatively small. Conclusion: This meta-analysis suggests that the administration of gabapentin is effective in reducing postoperative opioid consumption, VAS scores, and some side effects after spinal surgery.