Hemodynamic effects of fluid loading in acute massive pulmonary embolism

Abstract
To assess the hemodynamic effects of fluid loading in patients with acute circulatory failure caused by acute massive pulmonary embolism (AMPE). Prospective study. Respiratory critical care unit of a university hospital. Thirteen patients free of previous cardiopulmonary disease with angiographically proven AMPE (Miller index = 24 +/- 1), with acute circulatory failure defined by a cardiac index (CI) lower than 2.5 L/min/m2. Infusion of 500 mL of dextran 40 over 20 mins. Fluid loading induced a substantial increase in right atrial pressure from 9 +/- 1 mm Hg to 17 +/- 1 mm Hg and in right ventricular end-diastolic volume index from 123 +/- 14 mL/m2 to 150 +/- 11 mL/m2 (p < .05 for both comparisons). The increase in right ventricular preload was associated with an increase in CI from 1.6 +/- 0.1 to 2.0 +/- 0.1 L/min/m2 (p < .05), whereas right ventricular ejection fraction (15 +/- 3% at baseline vs. 16 +/- 3% after fluid loading) and total pulmonary vascular resistance index (1689 +/- 187 dyne[center dot]sec/cm5 [center dot]m2 at baseline vs. 1492 +/- 166 dyne[center dot]sec/cm (5) [center dot]m2 after fluid loading) remained unchanged. The increase in CI induced by fluid loading was inversely correlated to baseline right ventricular end-diastolic volume index (r = -.89; p < .05). These results suggest that fluid loading can improve hemodynamic status in patients with acute circulatory failure caused by AMPE. (Crit Care Med 1999; 27:540-544)