Table 1.

Summary of included studies

Reference Study design Country	Ketamine	Comparison	Outcomes
Ketamine intravenous vs opioids intravenous
Bronsky et al 25 2019 Retrospective cohort USA	n=79, ketamine 0.3 mg/kg intravenous every 20 min as needed, maximum three doses	n=79, fentanyl 2 µg/kg bolus intravenous over 1 to 2 min with additional dose every 10 min as needed	Change in pain scores, serious adverse events, GCS
Losvik et al 19 2015 Retrospective cohort Iraq	n=713, ketamine 0.2 mg/kg intravenous, in case of unrest, 5 mg diazepam intravenous. During protracted evacuations with repeated ketamine doses, 1 mg atropine was administered. Repeat doses of ketamine allowed.	n=888, pentazocine 0.4 mg/kg intravenous for adults, repeat doses allowed	Change in physiological severity score
Tran et al26 2014 Cluster—RCT Vietnam	n=169, ketamine 0.2 to 0.3 mg/kg was administered as slow intermittent intravenous injections	n=139, morphine administered in one single i.m. dose; 10 mg for adult patients, 5 mg for paediatric patients	Change in pain score, serious adverse events, adverse events, satisfaction, mean treatment time (head trauma)
Ketamine and morphine intravenous vs morphine intravenous alone
Galinski et al 23 2007 RCT France	n=33, ketamine 0.2 mg/kg intravenous in 3 mg morphine every 5 min if necessary	n=32, morphine 3 mg intravenous every 5 min if necessary	Change in pain score, adverse events
Jennings et al20 2012 RCT Australia	n=70, morphine 5 mg intravenous initial dose followed by a ketamine bolus of 10 or 20 mg according to body size, followed by 10 mg ketamine every 3 min thereafter until pain was relieved	n=65, morphine 5 mg intravenous initial dose followed by 5 mg intravenous every 5 min until pain was relieved	Change in pain score, adverse events, GCS
Johansson et al 24 2009 Prospective cohort Sweden	n=16, morphine 0.1 mg/kg intravenous followed by ketamine 0.2 mg/kg if pain score ≥4 after 5 min	n=11, mg/kg morphine 0.1 mg/kg intravenous followed by morphine 0.1 mg/kg if pain score ≥4 after 5 min	Change in pain score, adverse event, mean treatment time
Ketamine continuous intravenous administration vs ketamine intravenous one dose
Wiel et al 22 2015 RCT France	n=30, all patients received ketamine 0.2 mg/kg intravenous bolus combined with morphine 0.1 mg/kg intravenous followed by ketamine 0.2 mg/kg/h. Additional morphine 0.05 mg/kg was allowed every 5 min if VAS>3/10	n=33, all patients received a ketamine 0.2 mg/kg intravenous bolus combined with morphine 0.1 mg/kg intravenous followed by a saline infusion of the same volume. Additional morphine 0.05 mg/kg was allowed every 5 min if the VAS>3/10	Change in pain score, adverse events, satisfaction
Intranasal ketamine and inhaled nitrous oxide vs only inhaled nitrous oxide
Andolfatto et al212019 RCT Canada	n=60, all patients received approximately 0.75 mg/kg intranasal ketamine (30 mg for patients<50 kg, 50 mg for patients 50–100 kg, 75 mg for patients>100 kg) combined with inhaled nitrous oxide	n=60, all patients received inhaled nitrous oxide	Change in pain score, adverse events, satisfaction
Ketamine intravenous vs no analgesic treatment
Losvik et al 19 2015 Retrospective cohort Iraq	n=713, ketamine 0.2 mg/kg intravenous, in case of unrest, 5 mg diazepam intravenous. During protracted evacuations with repeated ketamine doses, 1 mg atropine was administered. Repeat doses of ketamine allowed.	n=275, no analgesic treatment	Change in physiological severity score

GCS, Glasgow coma scale; VAS, visual analogue scale.