SUMMARY

The haemodynamic effects of anaesthetic induction with i.v. etomidate have been assessed in 36 patients. The variables studied were recorded under basal conditions and 3 and 10 min after induction, before surgical stimulus. There was a reduction in cardiac output, stroke volume and arterial pressure, and a compensating increase in heart rate. Pulmonary arterial pressure and vascular resistance, central venous pressure and pulmonary capillary wedge pressure were virtually unchanged. Although etomidate has a negative inotropic effect, the variables which were depressed remained at all times within acceptable limits. Reneman and others (1975) demonstrated experi-mentally in dogs that i.v. administration of etomidate 1.5 mg kg"1 produced a slight decrease of the aortic pressure. At a dose of 2.5 mg kg"1, this was associated with an increase of the heart rate. Weymar and others (1974), using doses in the range 0.2-1.6 mg kg"1, observed a decrease in mean aortic pressure attri-butable to reduction of peripheral resistance, and a