Ketamine Infusion for Management of Early Postoperative Pain Following Elective Laparoscopic Cholecystectomy: Assessment of Optimum Dose

Abstract

Background: This study is aimed to assess an optimal dose of ketamine infusion for management of early postoperative pain in elective laparoscopic cholecystectomy. Intensity of pain, requirement of rescue analgesics and tness to discharge were assessed during immediate postoperative period. Methodology: Randomised controlled prospective clinical trial was conducted in 140 patients of laparoscopic cholecystectomy and, allocated in four groups of 35 each. Standard anaesthetic regimen was used in all patients, using propofol for induction, atracurium for muscle relaxation and isourane for maintenance of anaesthesia. Continuous infusion of the test drug was administered by intravenous cannula placed in alternate hand -1 -1 from start of port placement till wound closure. Group K1, K2 and K3 received an infusion of ketamine hydrochloride at a rate of 20 µg kg min , 30 -1 -1 -1 -1 µg kg min and, 40 µg kg min respectively, while Group N received normal saline. Postoperative pain score, requirement of rescue analgesia, degrees of sedation and postoperative cognitive function were examined postoperatively. Results: -1 Visual analog scale score ≥ 4 was considered signicant pain and, rescue analgesic injection diclofenac sodium 75mg kg was administered. Duration of analgesia was 130.71 ± 82.41, 457.14 ± 150.373, 520.97 ± 189.338 and, 524.83 ± 141.436 minutes in group N, K1, K2 and K3 respectively. Out of 35 patients 28, 4, 0 and, 0 patients required three doses of diclofenac sodium in 24 hours in N, K1, K2 and K3 group respectively. Conclusions: -1 -1 Continuous infusion of ketamine hydrochloride at a rate of 30 µg kg min during intraoperative period provide effective pain relief during early postoperative period without inuencing cognitive function of the patients.