Gabapentin for Perioperative Pain Management for Uterine Aspiration: A Randomized Controlled Trial

Abstract

Objective: To evaluate the effect of oral gabapentin in conjunction with usual oral pain management regimens of lorazepam, ibuprofen, oxycodone, and acetaminophen for surgical abortion on pain 5 minutes postprocedure.

Methods: This was a randomized, double-blind, placebo-controlled trial of patients from 6 0/7-14 6/7 weeks of gestation scheduled to undergo surgical abortion at the Duke Family Planning Clinic. Participants were administered 600 mg of oral gabapentin compared with placebo with usual oral pain management. Pain score was assessed using a 100-mm visual analog scale, with the primary outcome being pain score 5 minutes after the procedure. The effect of gabapentin was assessed using a linear regression model controlling for baseline pain. We also measured pain perception 24 hours after the procedure. Secondary outcome measures included anxiety, side effects, and usage of opiate pain medication in the 24-hour postoperative period.

Results: Out of 113 women screened for this study; 96 women were recruited, enrolled, and randomized to study treatment arm from August 2016 to June 2018. Pain at 5 minutes after the procedure was similar between the gabapentin and placebo groups ((Equation is included in full-text article.)=3.40; 95% CI -8.20 to 15.0; P=.56). Gabapentin and placebo were well tolerated, with no statistically significant difference in side effects or anxiety levels. Although prescription of opioids after the procedure was not standardized among patients, 73% of women received a short-term prescription for oxycodone. A lower percentage of women in the gabapentin group self-reported taking opioids in the 24 hours postprocedure (18% vs 47%; odds ratio 0.26; 95% CI 0.09-0.75).

Conclusion: The addition of gabapentin to usual oral pain management regimens with paracervical block did not reduce postoperative pain for patients undergoing outpatient surgical abortion. Although the addition of gabapentin was well tolerated and reduced oral opiate use 24 hours postprocedure, it did not affect the experience of pain during and immediately after the procedure.

Clinical trial registration: ClinicalTrials.gov, NCT02725710.

Conflict of interest statement

Financial Disclosure: Dr. Gray is an investigator for a phase 3 trial supported by Sebela for the Veracept IUD. This support is not related to the current study and did not overlap with the current study. She also reports money was paid to her institution for Duke AHEAD – a faculty development grant to support REDcap database and technical writing. The other authors did not report any potential conflicts of interest.

Figures

Figure 1.

CONSORT Flow Diagram of Participant Recruitment, Enrollment, Randomization, Follow-Up and Analysis.

Figure 2.

Mean Reported Pain Scores Throughout the Study, by Treatment Group.