Comparison between the Combination of Gabapentin, Ketamine, Lornoxicam, and Local Ropivacaine and Each of these Drugs Alone for Pain after Laparoscopic Cholecystectomy: A Randomized Trial

BackgroundThe main purpose of the study was to test whether the combination of gabapentin (600mg 4hours before surgery, 600mg after 24hours), ketamine (0.3mg/kg before anesthesia), lornoxicam (8mg before anesthesia and 8mg/12hours), and local ropivacaine (5mL 7.5% at insertion sites) provides superior analgesia to each of these drugs alone in the first 24hours after laparoscopic cholecystectomy. The secondary purpose was to examine whether this combination has less opioid-related side effects. MethodsThis was a 2-center randomized placebo-controlled trial. One hundred forty-eight patients, between 18 and 70years of age, were randomly assigned to 6 groups (28 in each group) with the use of computer software: A(gabapentin/ketamine/lornoxicam/ropivacaine); B(gabapentin/placebo/placebo/placebo); C (placebo/ketamine/placebo/placebo); D (placebo/placebo/lornoxicam/placebo); E (placebo/placebo/placebo/ropivacaine); and F (placebo/placebo/placebo/placebo). Only the principal investigator was aware of patients' allocation and provided drugs and placebo in covered prefilled syringes. The primary outcome of the study was the 24-hour morphine consumption. Secondary outcomes were frequency of opioid-related side effects (nausea, vomiting, sedation, pruritus, and dysuria). ResultsOnly groups A (6.4mg), B (9.46mg), and D (9.36mg) had lower morphine consumption than control group (20.29mg) (P<0.001, P=0.01, and P=0.008, respectively). Group A was not different from B and D (P=0.92, P=0.93). The only difference was in episodes of nausea between groups A (n=5) and the control group (n=12) (P=0.018). ConclusionThe combination of gabapentin, ketamine, lornoxicam, and local ropivacaine does not provide superior analgesia than gabapentin alone or lornoxicam alone after laparoscopic cholecystectomy. The combination reduces only the frequency of postoperative nausea, but larger studies are needed for safer results.