Gabapentin as an Adjunct for Pain Management During Dilation and Evacuation: A Double-blind Randomized Controlled Trial

Over 900,000 abortion procedures are performed annually in the United States [1]. For many women, pain relief during abortion is inadequate despite the use of non-steroidal anti-inflammatory drugs, local anesthetics, opioids, and/or moderate sedation. Research on pain control during abortion has focused on methods for relief during first-trimester suction curettage with little research dedicated to pain during dilation and evacuation (D&E). Gabapentin (Neurontin) has emerged as an effective adjunct to pain management for a variety of surgical procedures. Gabapentin is inexpensive and is also effective in reducing anxiety, nausea, and vomiting. The addition of pre-operative gabapentin to moderate sedation during D&E may lead to increased patient satisfaction and pain relief without significantly increasing risk or cost.

Proposed Research. The investigators propose a randomized controlled double-blinded trial evaluating the use of adjunct gabapentin versus placebo in addition to moderate sedation during D&E. The investigators hypothesize that 600 mg oral gabapentin administered pre-operatively at the time of cervical preparation initiation will improve intra-operative pain control. The investigators also hypothesize that it will improve pre- and post-operative pain, anxiety, nausea, vomiting, and overall satisfaction with pain management during D&E. The investigators hypothesize that the doses of moderate sedation agents required to obtain adequate sedation will be decreased if participants receive gabapentin, versus placebo. The investigators also plan to compare the risk of adverse events with adjunct gabapentin versus placebo with moderate sedation.

To test the hypotheses the investigators plan to enroll 130 participants who will be randomized 1 to 1 to receive either 600 mg gabapentin or placebo at the initiation of cervical preparation. Baseline characteristics will be recorded. Pain will be assessed pre-operatively, at 3 intraoperative time points, and postoperatively by 100 mm visual analog scale (VAS). The investigators plan to assess satisfaction with pain control, nausea, vomiting, and anxiety preoperatively and post-operatively, using 5-point Likert scales and the State Trait Anxiety Inventory, respectively. A final assessment will be made by phone on post-operative day one to evaluate overall satisfaction and perform a final screen for adverse events.

New features. No publications have evaluated the use of gabapentin during abortion care, although multiple studies are currently underway investigating gabapentin's effects during first trimester abortion and during overnight cervical osmotic dilators. To the investigators knowledge, this will be the first evaluation of gabapentin in conjunction with moderate sedation for pain relief during same-day second trimester abortion.