Ketamine as a component of multimodal analgesia for pain management in bariatric surgery: A systematic review and meta-analysis of randomized controlled trials.

Introduction: Anaesthesia in morbidly obese people is challenging with a high dose of opioid consumption. This systematic review and meta-analysis of randomised controlled trials (RCTs) summaries evidence comparing ketamine to placebo for pain management after bariatric surgery.
Methods: We used PRISMA 2020 and AMSTAR 2 guidelines to conduct this study. The random-effects model was adopted using Review Manager Version 5.3 for pooled estimates.
Results: Seven RCTs published between 2009 and 2021 were eligible, including a total of 412 patients (202 patients in the ketamine group and 210 patients in the control group). In the ketamine group total opioid consumption during the first 24 h postoperatively was reduced (mean difference, MD = -5.89; 95% CI [-10.39, -1.38], p = 0.01), lower pain score at 4 h (MD = -0.81; 95% CI [-1.52, -0.10], p = 0.03), pain score at 8 h (MD = -1.00; 95% CI [-1.21, -0.79], p < 0.01), and shorter hospital stay (MD = -0.10; 95% CI [-0.20, -0.01], p = 0.03). There was no significant difference between the two groups regarding duration of anaesthesia (MD = -3.42; 95% CI [-8.62, 1.82], p = 0.20), or sedation score (MD = -0.02; 95% CI [-0.21, 0.17], p = 0.84). As concern the postoperative complications, risks of postoperative nausea and vomiting(OR = 0.75; 95% CI [0.27, 2.04], p = 0.56), hallucinations (OR = 5.47; 95% CI [0.26, 117.23], p = 0.28), dizziness (OR = 1.05; 95% CI [0.14, 7.78], p = 0.96), and euphoria (OR = 5.77; 95% CI [0.65, 51.52], p = 0.12) were not different between the two groups either.
Conclusion: Ketamine could be an effective and safe technique for pain management following bariatric surgery. It reduces opioid consumption, postoperative pain, and hospital stay.RegistrationThis review was registered in PROSPERO (CRD42022296484).
Competing Interests: The authors declare that they have no conflict of interest.
(© 2022 The Authors.)