INFLUENCE OF DYING GASPS, YAWNS AND SIGHS ON BLOOD PRESSURE AND BLOOD FLOW

Abstract

Left and right ventricular pressures were recorded from dogs without operative entrance into the chest by means of hollow sounds inserted down the left carotid into the left ventricle and down the right jugular into the right ventricle. Normal inspiration increases venous return to the right heart and produces contour changes characteristic of larger and more prolonged effective ejection without significantly changing the duration of systole. Dying gasps, deep breathing, yawns and sighs which are generally considered as respiratory acts, markedly increase venous return. In the presence of cardiac arrest, dying gasps pump blood through the lungs and temporarily provide blood flow to the vital areas, the C. N. S. and heart. Effective pressures as great as 50 mm. Hg in the pulmonary artery, 50 mm. Hg in the coronary arteries and 40 mm. Hg in the C. N. S. arteries were created by dying gasps in dogs where cardiac action had ceased.