Hemodynamic effects of fluid loading in acute massive pulmonary embolism

Objective: To assess the hemodynamic effects of fluid loading in patients w ith acute circulatory failure caused by acute massive pulmonary embolism (A MPE). Design: Prospective study. Setting: Respiratory critical care unit of a university hospital. Patients: Thirteen patients free of previous cardiopulmonary disease with a ngiographically proven AMPE (Miller index = 24 +/- 1), with acute circulato ry failure defined by a cardiac index (CI) tower than 2.5 L/min/m(2). Intervention: Infusion of 500 mt of dextran 40 over 20 mins. Measurements and:Main Results: Fluid loading induced a substantial increase in right atrial pressure from 9 +/- mm Hg to 17 +/- 1 mm Hg: and in right Ventricular end-diastolic Volume index from 123 +/- 14 mL/m(2) to 150 +/- I I mL/m(2) (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/m(2) (p < .05), whereas right Ventricular ejection fraction (15 /- 3% at baseline vs. 16 +/- 3% after fluid loading) and total pulmonary va scular resistance index (1689 +/- 87 dyne.sec/cm(5).m(2) at baseline vs. 14 92 +/- 166 dyne.sec/cm(5).m(2) after fluid loading) remained unchanged. The increase in CI induced by fluid loading was inversely correlated to baseli ne right ventricular end diastolic volume index (r = -.89; p < .05). Conclusions: These results suggest that fluid loading can improve hemodynam ic status in patients with acute circulatory failure caused by AMPE.