Gabapentin for Peri-Operative Pain Relief in Office Gynecological Surgery: A Double-Blind Randomized Controlled Trial

Abstract

Background: This study aims to validate the use of gabapentin in peri-operative pain management for outpatient gynecological (GYN) office procedures using surgical abortion at gestational ages less than 24 weeks.

Methods: We conducted a double-blind, randomized, placebo-controlled trial of gabapentin in an ambulatory surgical abortion center. Eligible participants were patients 18 years of age and older, English or Spanish speaking, seeking a surgical elective abortion with pain management consisting of local anesthesia and intravenous sedation at gestational ages from 5 to 23 6/7 weeks. The study site was Birth Control Care Center, an affiliated clinic with the University of Nevada Las Vegas School of Medicine. Patients received routine pain control plus either placebo or gabapentin 600 mg 1 - 2 h prior to surgery. The primary outcome measured was post-operative pain scores using a 100-point (100 mm) visual analog scale at 5 min after the procedure. Additionally, pain scores were obtained at 30 min and 24 h post-procedure. Other secondary outcomes measured were nausea and vomiting at 5 min and 24 h post-procedure.

Results: From May 2017 to March 2018, 219 patients were recruited to this study from 400 patients who were offered participation. A total of 109 were randomized to gabapentin and 110 were randomized to placebo. Demographic characteristics, pregnancy history and general health conditions were similar. Pain scores at 5 min, 30 min and 24 h after the procedure were not significantly different between arms (P = 0.28), though pain was reported to decrease between 30 min and 24 h post-procedure (P < 0.001) for both groups. Nausea and vomiting were also not significantly reduced in the gabapentin group (P = 0.32 and 0.47), respectively.

Conclusions: Patients who received gabapentin, in combination with the routine intravenous pain control and local anesthesia for office-based surgical abortion did not experience less pain at 5 min, 30 min, nor at 24 h after the procedure, compared to the placebo group. Gabapentin did not appear to reduce pain at 24 h after the procedure and is therefore unlikely to reduce narcotic use in this clinic sample treated with intravenous (IV) sedation. Further, gabapentin was not useful to reduce nausea and vomiting post-operatively in this clinic sample.

J Clin Gynecol Obstet. 2020;9(4):96-101
doi: https://doi.org/10.14740/jcgo689