Ketamine as an analgesic in the pre-hospital setting: a systematic review

Background: Pain is a common presenting complaint and there is considerable debate regarding the best practice for analgesia in the pre-hospital environment for trauma patients with severe pain. Methods: A review of the literature was conducted using a number of electronic medical literature databases from their earliest record to the latest available at the time the search was conducted (May 2010). Medical Subject Headings, keywords and a pre-hospital search filter were used to yield relevant literature. Results: The search strategy yielded a total of 837 references. Seven hundred and fifty of these references were excluded as they did not meet the inclusion criteria. Of the 87 articles short listed for abstract or full-text review, six reported on ketamine use as an analgesic agent in the pre-hospital setting. Two papers were prospective randomized-controlled trials, and the number of patients included in the studies ranged from 4 to 164. Three studies aimed to report on the effectiveness of ketamine for pain intensity reduction; two concluded that ketamine provided safe and effective pain relief and one reported that ketamine reduced the amount of morphine required but was not associated with a reduction in pain intensity. One study identified a significantly higher prevalence of adverse effects following ketamine administration. The other studies reported no significant side effects and concluded that ketamine was safe. Conclusion: Ketamine is a safe and effective analgesic agent. The addition of ketamine as an analgesic agent may improve the management of patients presenting with acute traumatic pain in the pre-hospital setting.