Effect of Hypertonic Saline on the Pulmonary and Systemic Pressures

Abstract

The intravenous injection of 20 per cent saline in anesthetized closed chest dogs causes a rise in pulmonary venous, pulmonary arterial, right ventricular and peripheral venous pressures. Left atrial pressure does not change or falls, and systemic arterial pressure decreases very markedly. These changes are shown to result from spasm at the pulmonary vein--left atrial junction. Stimulation of chemoreceptors in this region is assumed to be the cause of the spasm.