(164) Low dose Ketamine for Opioid Tolerance and Pain

Abstract: Title: Ketamine for pain & Opioid Tolerance



Authors: Name, Name, Name



Background/Significance:

Ketamine is commonly used for anesthesia, analgesia, and agitation. A non-competitive antagonist of the N-methyl-d-aspartate (NMDA) receptor, Ketamine can be administered via intravenous, intramuscular, subcutaneous, oral, rectal, topical, intranasal, sublingual, epidural, and caudal routes. The wide variety of option for delivery facilitates multiple clinical and non-clinical environments. In light of this flexibility, our review addresses the more recent investigations into the unique ability ketamine to improve opioid tolerance.



Methods: For purposes of studies, reviews and programmatic innovations, describe what you did clearly and concisely.

While there are extensive reviews on the role of ketamine in anesthesia and analgesia, the publications of ketamine’s roles with opioids are limited. This review is based on a comprehensive literature search and summarizes findings in recent publications related to the mechanism of ketamine and its role in improving opioid tolerance.



Results:

Moderate evidence supports use of subanesthetic IV ketamine bolus doses (up to 0.35 mg/kg) and infusions (up to 1 mg/kg/h) as adjuncts to opioids for perioperative analgesia.



Discussion: Discuss your findings in a brief narrative.

Our review incorporated randomized-trials, case studies, and retrospective studies primarily from the last 10 years. Patients with acute pain who were receiving opioids were randomized to doses of ketamine (0.1 to 4 mg/kg/hr) or placebo. Endpoints evaluated include pain level, pain control satisfaction, side effects, sedation level, and pain medication levels. In randomized trails, there was lower total opioid dose in ketamine group (9.95 mg vs 12.81 mg; P=0.02), greater pain relief for ketamine groups vs control (SPID: 4 vs 7 vs 7.8; P< 0.02), and pain scores were lower in ketamine treatment groups (3.5 vs 6; P=0.018). Case studies also revealed that initiation of ketamine can reduce opioid requirements after tolerance had developed. Overall, the studies reviewed showed that minimal and low-dose ketamine are safe and effective at reducing post-operative opioid consumption and hyperalgesia.



Conclusion:

Low-dose ketamine is a prospective safe and effective option to help reduce opioid requirements and resolve opioid tolerance.