Acute pulmonary hypertension and right ventricular failure in adult respiratory distress syndrome.

The severity of acute pulmonary hypertension (APHT) in acute respiratory distress syndrome was examined in 20 patients. All patients had significant APHT (mean pressure 40.6 +/- 6.3 mmHg) on admission to the intensive care unit. There was evidence of right ventricular (RV) failure, with a right ventricular stroke work index (RVSWI) of 9.20 +/- 3.3 g.m/m2 and a central venous pressure of 18.0 +/- 4.0 mmHg. The RV afterload, i.e. pulmonary artery elastance (Ea = stroke volume/peak pulmonary artery pressure), was raised. Stroke volume could not be predicted from Ea or RVSWI alone, but regression analysis indicated that the ratio of RVSWI/Ea (i.e. ventriculo-arterial coupling) could account for 88% of the stroke volume.