Does etomidate increase vasopressor requirements in patients needing mechanical ventilation?

BACKGROUND: Single-dose etomidate is used as an induction agent for rapid-sequence intubation and is associated with transient adrenal insufficiency. There is ongoing debate as to the clinical consequences of this transient adrenal insufficiency for critically ill patients.
OBJECTIVE: To determine if the use of etomidate is associated with higher requirements for a vasopressor, relative to other induction agents, at a single time point (24 h after administration of the induction agent) in patients needing mechanical ventilation.
METHODS: In this retrospective observational study utilizing electronic health records, a convenience sample of 50 patients who had undergone intubation in the emergency department with etomidate were matched (1:1) with patients who had received other induction agents. Matching was based on primary admitting diagnosis relating to the cause of shock, APACHE II (Acute Physiology and Chronic Health Evaluation II) score, age, and sex. All patients were subsequently admitted to critical care areas for management. As a surrogate marker of hemodynamic instability, the vasopressor dose was recorded 24 h after intubation. Vasopressor doses were converted to norepinephrine equivalents for comparison.
RESULTS: The mean dose of vasopressors, in norepinephrine equivalents, was 4 μg/min(-1) for patients receiving etomidate and 3 μg/min(-1) for the control group (mean difference 0.7 μg min(-1), 95% confidence interval [CI] -1.9 to 3.2 μg min(-1), p = 0.61). Twelve of the patients in the etomidate group and 16 of those in the control group required the use of vasopressors at 24 h following intubation (odds ratio 2.3, 95% CI 0.53 to 13.99, p = 0.34).
CONCLUSIONS: Single-dose etomidate does not adversely affect hemodynamic stability, as measured by the dose of vasopressors required at 24 h after administration.