Etomidate Dosing for Induction of Anesthesia in Adults
The recommended dose of etomidate for induction of anesthesia in adults is 0.3 mg/kg administered intravenously over 30 to 60 seconds, with an acceptable range of 0.2 to 0.6 mg/kg depending on patient factors. 1
Standard Dosing Protocol
The FDA-approved dose is 0.3 mg/kg IV, injected over 30 to 60 seconds for induction of anesthesia in adults and pediatric patients above age 10 years 1
The acceptable dosing range extends from 0.2 mg/kg to 0.6 mg/kg, which must be individualized based on clinical context 1
For rapid sequence intubation in critically ill adults, the Society of Critical Care Medicine specifically recommends 0.3 mg/kg IV as the standard dose 2
Dose Adjustments for Specific Populations
Geriatric patients may require reduced doses of etomidate, though specific dose reductions are not quantified in the FDA labeling 1
Higher doses (>0.3 mg/kg) have been associated with increased risk of respiratory depression, particularly in older patients 2
Patients over 55 years receiving doses ≥0.23 mg/kg demonstrated higher rates of oxygen desaturation requiring supplemental oxygen 3
Alternative Dosing Strategies
For neurosurgical patients requiring deeper cortical depression, doses of 0.5 to 1.7 mg/kg titrated to early burst suppression on EEG have been studied and provide superior hemodynamic stability during laryngoscopy compared to standard doses 4
Lower doses of 0.4 to 0.6 mg/kg titrated to an EEG spectral edge frequency of 10 to 12 Hz represent an intermediate approach 4
For maintenance of anesthesia during short procedures, smaller incremental doses (smaller than the original induction dose) may be administered to supplement subpotent anesthetic agents like nitrous oxide, though this use has insufficient data in pediatric patients 1
Clinical Pearls and Caveats
Etomidate provides minimal hemodynamic disturbance compared to other induction agents, with only an 8.5% reduction in mean arterial pressure and 2.8% increase in heart rate at 0.2 mg/kg 5
The onset of anesthesia occurs within 10 seconds, with a mean duration of 6 to 8 minutes 5
Myoclonus occurs in approximately one-third of patients when premedicated with diazepam and fentanyl, but can occur in two-thirds without these precautions 6
Pain at the injection site is more frequent with etomidate compared to barbiturates, particularly when injected into arm veins 6
Vomiting occurs in 4-10% of patients receiving etomidate 2
Etomidate causes transient adrenal suppression, but the Society of Critical Care Medicine does not recommend routine corticosteroid administration following a single induction dose 2
Etomidate is compatible with commonly administered premedications and does not significantly alter the usual dosage requirements of neuromuscular blocking agents 1