Background: Co-administration of ketamine and remifentanil may offer preemptive analgesia and prevention of opioid-induced hyperalgesia, resulting in reduction of postoperative pain.
Methods: We retrospectively analyzed data concerning anesthetic management and postoperative pain management in 19 adult patients undergoing elective laparotomy with general anesthesia using ketamine and remifentanil.
Results: Ketamine and remifentanil were co-administered for both induction and maintenance of general anesthesia. Preoperative and total doses of ketamine were 1.4+/-0.5 and 1.9+/-0.4 mg x kg(-1). Infusion rate of remifentanil at the beginning of surgery was 0.24+/-0.02 microg x kg(-1) x min(-1), and minimal and maximal rate were 0.06+/-0.03 and 0.26+/-0.03 microg x kg(-1) min(-1). Pentazocine and nonsteroidal anti-inflammatory drugs (NSAIDs) were used for postoperative pain management. Consumption of pentazocine was 0.51+/-0.33 mg x kg(-1) on 1st postoperative day (1POD), and NSAIDs were co-administered on 1POD for 3 patients. Most patients could stand up and walk on 1POD.
Conclusions: Results in this study suggest that anesthetic management using ketamine and remifentanil may be useful for postoperative pain management, probably by preemptive analgesic effects of both agents and preventive effects of ketamine against opioid-induced hyperalgesia.