Low-Dose Nebulised Ketamine Offers Comparable Pain Control as Higher Doses in Emergency Department Setting

November 3, 2021

By Louise Gagnon

VIRTUAL -- November 3, 2021 -- Results of a randomised trial presented at the 2021 Annual Meeting of the American College of Emergency Physicians (ACEP) suggest that of 3 possible doses of nebulised ketamine studied, the lowest dose offered as much short-term pain control as the next highest and the highest dose for painful conditions in the emergency department. 

“We were looking for the ideal dose for pain control,” explained Ashley Davis, MD, Maimonides Medical Center, Brooklyn, New York. “We looked at 3 different doses which were 0.75 mg/kg, 1.0 mg/kg, and 1.5 mg/kg.”

Dr. Davis noted that, in the emergency department, when intravenous access is not readily available or obtainable, subdissociative-dose ketamine can be administered through intranasal and nebulised routes for management of acute pain. 

The current study included 120 patients aged 18 years and older. Subjects used an 11-point numeric rating scale to denote their pain. The difference in mean pain scores at 30 minutes between the 0.75 mg/kg and 1 mg/kg groups was 0.25; between the 1 mg/kg and 1.5 mg/kg groups was -.225; and between the 0.75 mg/kg and 1.5 mg/kg groups was 0.025.

There were no clinically concerning changes in vital signs between groups, and no serious adverse events occurred in any of the groups.

“We saw the same effect [in pain control] across the board, so there’s no need to use a higher dosage,” said Dr. Davis. 

The investigators also looked at whether subjects needed an additional dose of ketamine at 30 minutes or thereafter or rescue morphine and did not find a significant difference across the t3 arms.

A limitation of the study is that it was a single-center investigation and that only 3 out of 120 subjects had chronic pain as their chief complaint. Also, the majority of subjects in the study suffered from acute musculoskeletal pain.

Dr. Davis and colleagues are conducting another study comparing nebulised ketamine to intravenous ketamine in terms of pain control ability.

[Presentation title: Nebulized Ketamine at 3 Different Dosing Regimens for Painful Conditions in the Emergency Department. Abstract 195]