Gabapentin Effective for Pain Following Bariatric Surgery

The authors of a systematic review and meta-analysis published in the Journal of PeriAnesthesia Nursing found that gabapentin was effective at managing pain experienced by patients following bariatric surgery.

Investigators from Texas Wesleyan University and O’Connor Hospital in the United States searched publication databases through July 2021 for randomized controlled trials of presurgical gabapentin administration for the control of postoperative pain following bariatric surgery. A total of 4 studies were included in the analysis.

The studies were published between 2015 and 2019 and conducted in Saudi Arabia (n=2), Iran (n=1), and Poland (n=1). Patients (N=283) with a body mass index (BMI) greater than 35 kg/m² underwent either sleeve gastrectomy or gastric bypass. Three studies evaluated the efficacy of gabapentin 1200 mg, and the fourth study evaluated gabapentin 100 mg.

Compared with placebo, presurgical administration of gabapentin was associated with significantly lower pain at arrival to the postanesthesia care unit (mean difference [MD], -1.98; 95% CI, -3.66 to -0.29; I², 93%; P =.02), 2 hours after surgery (MD, -0.74; 95% CI, -1.04 to -0.43; I², 0%; P <.00001), 4 hours after surgery (MD, -1.23; 95% CI, -2.23 to -0.07; I², 95%; P =.04), 12 hours after surgery (MD, -0.88; 95% CI, -1.71 to -0.04; I², 87%; P =.04), and overall (MD, -1.04; 95% CI, -1.45 to -0.63; I², 90%; P <.00001).

In a test for subgroup differences, a significant effect was observed (c², 10.06; P =.04), indicating effects of gabapentin dose, timing of gabapentin administration, and surgical approach.

Gabapentin was also associated with reduced opioid consumption compared with placebo (MD, -7.89; 95% CI, -13.56 to -2.2 mg; I², 97%; P =.006).

Fewer recipients of gabapentin were completely awake at arrival to the postanesthesia care unit (risk ratio [RR], 0.15; 95% CI, 0.04-0.62; P =.009), 1 hour after surgery (RR, 0.33; 95% CI, 0.12-0.92; P =.03), 2 hours after surgery (RR, 0.38; 95% CI, 0.17-0.83; P =.01), and 6 hours after surgery (RR, 0.23; 95% CI, 0.07-0.73; P =.01) compared with recipients of placebo.

The incidence of respiratory depression, pruritus, nausea, and vomiting tended to not differ between recipients of gabapentin and those receiving placebo (RR, 0.61; 95% CI, 0.38-1.00; I², 3%; P =.05). Gabapentin was not associated with increased risk for dizziness (odds ratio [OR], 1.01; 95% CI, 0.40-2.54; I², 0%; P =.99) or headache (RR, 0.76; 95% CI, 0.25-2.30; I², 0%; P =.62) compared with placebo.

This analysis may have been limited, as the data were insufficient to evaluate rates of rescue pain medication use.

Study authors conclude that presurgical administration of gabapentin was associated with reduced pain and opioid consumption compared with placebo among patients undergoing bariatric surgery. However, the study authors caution that “there is very limited data on the opioid-sparing effects of gabapentin in bariatric surgery.” Additional studies are needed to confirm these findings as significant study heterogeneity was observed.