Central Venous Pressure and Pulmonary Wedge Pressure

Abstract
• To determine the reliability of central venous pressure (CVP) as a guide to fluid therapy during an operation, repeated and simultaneous CVP and pulmonary wedge pressure (PWP) measurements were made with a Swan-Ganz catheter in 13 relatively elderly patients without obvious cardiac or respiratory disease. Overall correlation between CVP and PWP was highly significant (P<.001); there was, however, an important variation of the correlation for each patient. For values of CVP≥8 mm Hg, the correlation was not significant. The disparity between right and left ventricular filling pressures was confirmed by the relationship between serial changes in CVP and PWP. These data strongly suggest that in relatively elderly patients undergoing surgery without evidence of cardiac or respiratory disease, CVP may be a misleading index for appreciating PWP. (Arch Surg 111:1122-1125, 1976)