Low-dose ketamine for analgesia in the ED: A retrospective case series

Objectives: The aim of this study was to describe the use and effect of low-dose ketamine (LDK) for analgesia in the emergency department (ED). Methods: A chart review was performed to identify all adult patients who received LDK for analgesia in our ED. Cases were identified by pharmacy record of ketamine administration. Low-dose ketamine was defined as the administration of 0.1 to 0.6 mg/kg of ketamine for pain control. Use of ketamine during procedural sedation was excluded. Data were analyzed descriptively. Results: Thirty-five cases in which patients received LDK in the ED for a 2-year period were identified. Doses ranged from 5 to 35 mg. Administration was intravenous in 30 (86%) of 35 cases and intramuscular in 5 (14%) of 35 cases. Opioids were administered before or coadministered with LDK in 32 (91%) of 35 cases, and in the remaining 3 cases, opioids were used before the patient came to the ED. Improvement in pain was observed in 19 (54%) of 35 cases in which patients received LDK. Pain scores did not improve in 8 (23%) of 35 cases. Insufficient data were available to determine LDK effect for 8 (23%) of 35 cases. No significant adverse events were identified in any of the 35 cases. Conclusions: The administration of LDK in the ED may be a safe and effective adjunct for analgesia in some patients. However, prospective randomized controlled trials are needed before widespread use of LDK for analgesia in the ED can be recommended.