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

ObjectivesThe aim of this study was to describe the use and effect of low-dose ketamine (LDK) for analgesia in the emergency department (ED).MethodsA 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.ResultsThirty-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.ConclusionsThe 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.