Cardiovascular alterations in the adult respiratory distress syndrome.

We reviewed the hemodynamic data of 27 patients with severe adult respiratory distress syndrome (ARDS) and found significant elevations in heart rate, pulmonary artery pressure, and pulmonary vascular resistance and depressions of stroke index and left ventricular stroke work index. Altered left ventricular performance was suggested by a left ventricular stroke work index lower than expected for the level of wedge pressure in 19 patients and decreased slopes in nine of 11 ventricular function curves. Hemodynamic values in a subgroup receiving 0 to 5 cm H2O of positive end expiratory pressure (PEEP) were similar to those in the overall group (mean PEEP 12.5 +/- 7.9 cm H2O). Improvement in pulmonary and systemic hemodynamics occurred in survivors. Eight of 11 patients who underwent postmortem examination had cardiac abnormalities. The findings in this study suggest that changes in cardiovascular performance commonly occur in severe ARDS and that several mechanisms may contribute to the alterations.