Cerebral blood flow and metabolic response to etomidate and ischemia

The purpose of this study was to measure the cerebrovascular and metabolic effects of etomidate during cerebral aneurysm surgery. Flow probes were placed on brain arteries to measure regional tissue perfusion. Cerebral oxygen consumption (CMRO2) was determined from blood flow measures and arterial-jugular bulb oxygen content differences. CBF and CMRO2 decreased 40% during etomidate infusion to suppress the electroencephalogram. During temporary brain artery occlusion, measurement of arterial blood flow in the circle of Willis provides an indication of collateral blood flow to potentially ischemic territory. The use of multiple flow probes can provide information on the effect of anesthetic drugs and surgical manipulation on cerebral circulation.