Increased plasma concentrations of brain natriuretic peptide in patients with acute lung injury

Abstract

Purpose : This study was performed to elucidate the pathophysiological role of brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) in acute lung injury. Materials and Methods : We sequentially measured plasma concentrations of immunoreactive BNP and ANP in 10 patients (mean age, 63 years) with acute lung injury and compared those with hemodynamic parameters and pulmonary functions. Results : Plasma concentrations of immunoreactive BNP and ANP were markedly elevated at entry into the study. Plasma BNP concentrations during the early course (3 days) showed significant ( P < .01) positive correlations with systemic vascular resistance index ( r = .708) and pulmonary vascular resistance index ( r = .573), but a negative correlation with cardiac index ( r = −.608). Plasma ANP concentrations showed a significant ( P < .05) positive correlation with pulmonary capillary wedge pressure ( r = .398). Plasma BNP in 4 patients who died and 1 patient with acute renal failure remained elevated during the entire hospital length of stay (12 days). Conclusion : These findings suggest that circulating BNP plays an important role in acute lung injury along with ANP as a compensatory mechanism for cardiac dysfunction accompanied by increased systemic vascular resistance index and pulmonary vascular resistance index. Circulating BNP may be a sensitive humoral marker for the degree of ventricular dysfunction associated with acute lung injury.