Objective:Patients with opioid use disorder (OUD) present significant challenges in perioperative pain management due to opioid tolerance, opioid-induced hyperalgesia, withdrawal risk, and interactions with medications for OUD such as methadone and buprenorphine. Ketamine, an N-methyl-D-aspartate receptor antagonist with analgesic and antihyperalgesic properties, has been investigated as an adjunct to improve perioperative analgesia and reduce opioid exposure in this population, but existing evidence is fragmented across surgical contexts, dosing strategies, and outcome measures.
Method:Following PRISMA-ScR guidelines, electronic searches of PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov identified randomized or pilot randomized clinical trials published between January 2010 and January 2025. Studies involving pediatric populations, non-perioperative ketamine use, or lacking postoperative pain or opioid outcomes were excluded.
Results:Six trials involving 860 patients met inclusion criteria. Surgical contexts included orthopedic procedures, lumbar spine surgery, and other operations involving chronic opioid dependence. Ketamine was administered as intravenous bolus dosing, continuous infusion, or combined bolus–infusion regimens. Across studies, ketamine reduced early postoperative opioid requirements, with absolute reductions of approximately 10–35 morphine milligram equivalents within 24–48 hours, and several trials reported 1–2-point decreases in early postoperative pain scores. Safety profiles were acceptable, with mild psychoperceptual effects in fewer than 5% of patients and no increases in serious adverse events.
Method:Following PRISMA-ScR guidelines, electronic searches of PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov identified randomized or pilot randomized clinical trials published between January 2010 and January 2025. Studies involving pediatric populations, non-perioperative ketamine use, or lacking postoperative pain or opioid outcomes were excluded.
Results:Six trials involving 860 patients met inclusion criteria. Surgical contexts included orthopedic procedures, lumbar spine surgery, and other operations involving chronic opioid dependence. Ketamine was administered as intravenous bolus dosing, continuous infusion, or combined bolus–infusion regimens. Across studies, ketamine reduced early postoperative opioid requirements, with absolute reductions of approximately 10–35 morphine milligram equivalents within 24–48 hours, and several trials reported 1–2-point decreases in early postoperative pain scores. Safety profiles were acceptable, with mild psychoperceptual effects in fewer than 5% of patients and no increases in serious adverse events.