Gabapentin as an adjunct for pain management during dilation and evacuation: A double-blind randomized controlled trial

Abstract

ObjectivesTo assess the analgesic efficacy of preoperative gabapentin among patients undergoing dilation and evacuation (D&E) with moderate sedation. Study designWe conducted a randomized, controlled, double-blind trial among patients undergoing same-day D&E at 14 to 19 weeks gestation under moderate sedation. We randomized participants 1:1 to gabapentin 600 mg or placebo after cervical preparation at least 1 hour prior to D&E. We assessed pain using a 100-mm visual analog scale before, during, and after the procedure. The primary outcome was postoperative recall of maximum procedural pain with a 13-mm a priori threshold for clinical significance. We standardized initial fentanyl and midazolam dosing. We assessed satisfaction with pain control, nausea, and vomiting via Likert scales and anxiety using a validated instrument. ResultsWe enrolled 126 participants and randomized 61 to gabapentin and 65 to placebo, with study medication administered a mean of 211 (SD 64) minutes preoperatively. Recall of maximum pain was 41 mm for gabapentin and 49 mm for placebo (p = 0.24). Gabapentin resulted in reduced pain during uterine aspiration (56 vs 71 mm, p= 0.003) compared to placebo, but not for any other time points. The gabapentin group had higher satisfaction (78% vs 65% very or somewhat satisfied, p= 0.01). Median fentanyl dose was lower in the gabapentin group (75 vs 100 mcg, p = 0.005). Midazolam dose, nausea, vomiting, and anxiety did not differ between groups. No serious adverse events occurred in the gabapentin group. Sedation reversal was not required. ConclusionsThe addition of gabapentin to moderate sedation during D&E did not result in lower maximum recalled procedural pain. Gabapentin resulted in reduced intra-operative pain during uterine aspiration and increased satisfaction with pain control. ImplicationsGabapentin reduces intraoperative pain and improves satisfaction with pain management when administered prior to second-trimester surgical abortion and may be considered as an adjunct to intravenous sedation. Moderate sedation may impair assessment and recall of pain. Additional research is needed to identify the most effective pain management regimens for D&E.