Background: Inadequate analgesia is common after shoulder arthroscopy. Both interscalene blocks and gabapentin are effective methods of pain management under various circumstances. We tested the hypothesis that gabapentin augments postoperative analgesia provided by interscalene brachial plexus block in patients having ambulatory arthroscopic shoulder surgery.
Methods: Sixty patients were randomly assigned to receive oral gabapentin, 800 mg, or placebo 2 h before surgery. An interscalene brachial plexus block with 0.3 mL/kg of 0.5% ropivacaine was performed. General anesthesia was maintained with sevoflurane and included a single 1-microg/kg dose of remifentanil. Postoperative analgesia was initially provided with morphine and subsequently with ketoprofene (150 mg orally twice daily) and a combination of 400 mg acetaminophen and 30 mg dextropropoxyphene as needed. Pain scores, analgesic requirements, and side effects were assessed in the ambulatory unit and at home for 48 h.
Results: Emergence from general anesthesia was similar in both groups. There were no significant differences in pain scores, first postoperative request for analgesia, or oral analgesic consumption. The incidence of side effects was comparable in both groups, except that headaches were less frequent in the gabapentin group.
Conclusion: A single preoperative dose of gabapentin (800 mg) does not augment postoperative analgesia in patients given interscalene brachial plexus blocks for arthroscopic shoulder surgery.