Influence of Respiration on Arterial, and Right and Left Ventricular Pressures

Abstract

The pressures transmitted through catheters inserted via the carotid artery and jugular vein into the left and right ventricles of dogs were recorded by means of a strain gage and oscillograph. Femoral arterial pressure was similarly recorded through a small plastic catheter. The pressure variations occurring in the trachea with respiration were recorded via a needle or intratracheal tube. The arterial and left ventricular pressures were reduced at the onset of inspiration but after 1 or 2 heart beats rose during the remainder of inspiration. With the onset of expiration arterial and left ventricular pressures were elevated but after 2 or 3 heart beats declined during the remainder of expiration. The pressure changes with respiration in the right ventricle were almost completely out of phase with those in the left ventricle.