Etomidate or Ketamine to Avoid Peri-Intubation Hypotension?
Benton R. Hunter, MD
In a large observational registry study, ketamine was associated with a higher risk for hypotensive events than etomidate.
Single-dose etomidate for emergency intubation is considered hemodynamically stable, but some authors have postulated that ketamine, which induces catecholamine release, may be safer for patients at risk for hypotension.
These authors queried an international, prospective, observational database of emergency department intubations to identify patients ≥14 years old who received ketamine or etomidate as the induction agent and had preprocedural systolic blood pressures between 100 mm and 139 mm Hg. Of 19,071 intubations in the database from 2016 through 2018, 6806 met the inclusion criteria (738 ketamine, 6068 etomidate).
Patients intubated with ketamine were significantly more likely to have difficult airway characteristics (69% vs. 60%), to undergo video laryngoscopy (59% vs. 51%), to have suspected sepsis (20% vs. 11%), and to receive rocuronium as opposed to succinylcholine (63% vs. 51%). Peri-intubation hypotension (systolic BP <100 mm Hg) occurred in 18% of ketamine recipients and 12% of etomidate recipients. In multivariable analysis, ketamine was associated with hypotension (adjusted odds ratio, 1.4). Ketamine recipients were more likely to receive treatment for hypotension. These differences were noted in medical, but not trauma, patients. Rates of mortality, first-pass success, and peri-intubation arrest were similar between groups.
I’m most concerned about patients who are hypotensive before intubation, but they were not included in this analysis. Significant baseline differences between ketamine and etomidate recipients and lack of measure of, or adjustment for, baseline blood pressure prohibit any conclusion that etomidate may be superior. However, there is also no evidence that ketamine reduces the risk of hypotension in this setting, and this study suggests that ketamine need not be prioritized over etomidate for patients at risk for peri-intubation hypotension.
April MD et al. Ketamine versus etomidate and peri-intubation hypotension: A National Emergency Airway Registry study. Acad Emerg Med 2020 Jun 26; [e-pub].
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