A STUDY OF PULMONARY VENOUS AND ARTERIAL PRESSURES AND OTHER VARIABLES IN THE ANESTHETIZED DOG BY FLEXIBLE CATHETER TECHNIQUES

Abstract

Studies were made in 64 dogs anesthetized with nembutal, 30 mg./kg.,of pulmonary artery and venous pressures measured with a Statham strain-gauge attached to flexible catheters. Simultaneously, cardiac output, intrathoracic pressure, systemic arterial and venous pressures were recorded. Left heart catheterization was attended by a mortality of about 10%. Observations on animals not in cardiac failure show significant positive correlations between systemic arterial pressure and (a) integrated mean pulmonary artery pressure, (b) integrated mean pulmonary venous pressure and (c) cardiac index. A significant positive correlation was also found between mean pulmonary venous pressure and cardiac index. Although the mean systemic venous pressure was higher in dogs with low cardiac indices, the difference was not statistically significant.