The Efficacy of Ketamine Administration in Prehospital Pain Management of Trauma Patients; a Systematic Review and Meta-Analysis

INTRODUCTION: Although previous articles and reviews suggest that ketamine might effectively manage pain in trauma patients, these articles have serious limitations. Accordingly, the current meta-analysis aims to investigate the efficacy of ketamine administration in prehospital pain management of trauma patients. METHOD: In the present meta-analysis, controlled human studies were included. An extensive search was conducted in electronic databases including Medline (via PubMed), Embase, Central, Scopus, Web of Science, and ProQuest, gathering data to the end of 2018. The efficacy and side effects of ketamine administration in pre-hospital pain management were compared with those of opioid analgesics based on standard mean difference (SMD) and odds ratio (OR) calculations with 95% confidence interval (95% CI). RESULTS: Data from seven articles were included in the present meta-analysis. Ketamine administration was not more effective than administrating morphine or fentanyl in prehospital pain management of trauma patients (SMD = -0.56, 95% CI: -1.38 to 0.26, p = 0.117). However, co-administration of ketamine+morphine was considerably more effective than ketamine alone, in alleviating pain in prehospital settings (SMD = -0.62, 95% CI: -1.12 to -0.12, p = 0.010). Finally, it was concluded that ketamine alone had less side effects than morphine alone (OR = 0.25, 95% CI: 0.11 to 0.56, p = 0.001). However, co-administration of ketamine+morphine increases the risk of side effects to 3.68 times compared to when morphine is prescribed solely (OR=3.68, 95% CI: 1.99 to 6.82, p<0.001). CONCLUSION: For the first time, findings of the current meta-analysis demonstrated that ketamine, being administered alone, is an effective and safe medication in prehospital pain management in trauma patients, and can be considered as an acceptable alternative to opioid analgesics.