Remifentanil-induced Postoperative Hyperalgesia and Its Prevention with Small-dose Ketamine
Anesthesiology June 27, 2005 Vincent Joly, Philippe Richebé, B. Guignard et al. 624 citations
A relatively large dose of the opioid remifentanil given during surgery triggers increased pain sensitivity after the operation, a phenomenon called secondary hyperalgesia. In a trial of 75 patients undergoing major abdominal surgery, those who received a high intraoperative dose of remifentanil (0.40 µg/kg/min) had greater pain sensitivity around the surgical wound and required more morphine for pain relief than patients who received a low dose (0.05 µg/kg/min). Adding a small dose of the drug ketamine during surgery prevented this heightened pain sensitivity, suggesting that remifentanil-induced hyperalgesia involves an N-methyl-d-aspartate pain-facilitator process. No significant differences were seen in overall pain scores, pressure pain thresholds, breathing tests, cognitive function, or side effects among the groups.