Single Dose versus Weight Based Dose Intra Nasal Ketamine for ED Management of Acute Musculoskeletal Pain

Abstract

Background: Ketamine has been used widely in emergency departments for different procedures, prescribed only as a single dose or dose per weight. We compared single dose of ketamine with dose per weight ketamine for procedures done in cases with acute musculoskeletal pain. Methods: This randomized double blind clinical trial, was conducted in the emergency department of Imam Khomeini Hospital during March and June 2012. Patients with traumatic or non-traumatic musculoskeletal pain with numeric rating scale (NRS) ≥ 4 were enrolled. Patients were divided to Weight groups and for each group 4 syringes with the same shape were considered. BP, PR, RR, O2 sat, level of consciousness and all complications were checked for the patients in minutes 20 and 30. First group received 50 mg and second group received 0.75 mg/kg intranasal ketamine. Results: Out of 136 patients enrolled in this study, 27 cases were excluded. Patients were divided to two groups of 60 (dose per kg) and 59 (single dose) persons. The most type of injuries were fractures (37.8%) followed by lacerations (26%). O 2 sat, HR, systolic and diastolic BP and Mean NRSs before and after procedures were not significantly different in the two groups. Mean NRS reduction was not significant between two groups (comparing NRS at baseline with NRS at minutes 30, 40 and 60). Discussion: Our study showed that 50 mg single dose of ketamine is the same as the 0.75 mg/kg dose per weight for reducing pain in cases with traumatic and non-traumatic musculoskeletal injuries.