Interaction of right and left ventricular filling pressures at the termination of cardiopulmonary bypass. Central venous pressure/pulmonary capillary wedge pressure ratio.

In 50 patients who underwent coronary bypass grafting, the interaction of left- and right-sided filling pressures were prospectively evaluated to determine whether restoration and/or maintainance of a normal central venous pressure/pulmonary capillary wedge pressure (CVP/PCWP) ratio could improve biventricular performance. In 40 patients, the CVP/PCWP ratio was normal (less than 1) and termination of cardiopulmonary bypass was uneventful. In 10 patients, during loading at the termination of extracorporeal circulation, CVP exceeded PCWP and the ratio was reversed (less than 1). Cardiac index and systolic arterial pressure were low. Restoration of normal ratio by emptying the right heart helped in the improvement of systolic arterial pressure and cardiac index. Thus, in the presence of reversed CVP/PCWP ratio at the termination of cardiopulmonary bypass, restoration of the ratio may prevent unnecessary pharmacologic and/or mechanical intervention, such as inotropic agents, balloon pumps, or assist devices.