Determination of systemic vascular resistance by a noninvasive technic.

SUMMARY Measurement of systemic vascular resistance in man currently requires arterial and venous cannulation, so that cardiac output and mean arterial blood pressure may be simultaneously determined. This report describes a noninvasive technic for determining systemic vascular resistance (SVR.), utilizing an ultrasonic method for cardiac output measurement, and a combination of sphygmomanometry and external carotid pulse tracing analysis for determination of mean arterial blood pressure. SVR0 was measured by this technic in 18 patients and compared with systemic vascular resistance determined by conventional methods at cardiac catheterization (SVR,).