EFFICACY OF LOW-DOSE KETAMINE AS AN ADJUVANT ANALGESIC IN POSTOPERATIVE PAIN MANAGEMENT AFTER ABDOMINAL SURGERY: A SYSTEMATIC REVIEW

Introduction: Postoperative pain after abdominal surgery remains a major clinical challenge, frequently requiring multimodal analgesic strategies to optimize patient recovery and reduce opioid-related adverse effects. Objective: The primary objective of this systematic review was to evaluate the efficacy of low-dose ketamine as an adjuvant analgesic in postoperative pain management after abdominal surgery, with secondary objectives focusing on opioid-sparing effects, safety profile, impact on postoperative recovery, heterogeneity across surgical procedures, and implications for clinical practice. Methods: A systematic search was conducted in PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ClinicalTrials.gov, and the International Clinical Trials Registry Platform, including randomized and non-randomized studies evaluating low-dose ketamine administered perioperatively in adult patients undergoing abdominal surgery, with outcomes synthesized narratively and, when appropriate, quantitatively. Results and Discussion: A total of 20 studies met the inclusion criteria, demonstrating that low-dose ketamine, when used as an adjuvant to standard analgesic regimens, was associated with reduced postoperative pain scores and decreased opioid consumption in most surgical contexts, although variability in dosing strategies and outcome measures contributed to heterogeneity. Conclusion: Low-dose ketamine appears to be an effective and generally safe adjuvant analgesic for postoperative pain control after abdominal surgery, supporting its selective use within multimodal analgesia protocols tailored to individual patient and procedural characteristics.