B-type natriuretic peptide in the assessment of acute lung injury and cardiogenic pulmonary edema

OBJECTIVE: The role of plasma B-type natriuretic peptide (BNP) in critically ill patients with acute pulmonary edema is controversial. We postulated that a low BNP level would exclude cardiac dysfunction as the principal cause of pulmonary edema and therefore help in the diagnosis of acute lung injury. DESIGN: A retrospective derivation cohort was followed by a prospective validation cohort of consecutive patients with acute pulmonary edema admitted to three intensive care units. BNP was measured within 24 hrs from onset. Critical care experts blinded to BNP results integrated clinical data with the course of disease and response to therapy and served as the reference standard. SETTING: Three intensive care units at the tertiary center. PATIENTS: Consecutive critically ill patients with acute pulmonary edema. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: In a derivation cohort of 84 patients, a BNP threshold of