Assessment of acute lung injury/acute respiratory distress syndrome using B-type brain natriuretic peptide

OBJECTIVES: To investigate the clinical value of B-type natriuretic peptide (BNP) in the assessment of severity and prognosis in acute lung injury/acute respiratory distress syndrome (ALI/ARDS). METHODS: Plasma BNP level, arterial blood gases, serum C-reactive protein level, alveolar-arterial oxygen tension difference and oxygenation index were measured in patients with and without ALI/ARDS within 24 h of admission to an intensive care unit. Patients with ALI/ARDS were divided into mild, moderate or severe groups according to the degree of hypoxaemia. Survival >28 days was recorded. RESULTS: A total of 59 patients with ALI/ARDS and 14 patients without ALI/ARDS were included in the study. Of the patients with ALI/ARDS, 18 had mild hypoxaemia, 20 had moderate hypoxaemia and 21 had severe hypoxaemia. The mean ± SD BNP level was significantly higher in all three ALI/ARDS groups (92.41 ± 28.19 pg/ml, 170.64 ± 57.34 pg/ml and 239.06 ± 59.62 pg/ml, respectively, in the mild, moderate and severe groups) than in the non-ALI/ARDS group (47.27 ± 19.63 pg/ml); the increase in BNP level with increasing severity was also statistically significant. When divided according to outcome, the BNP level in the death group (267.07 ± 45.06 pg/ml) was significantly higher than in the survival group (128.99 ± 45.42 pg/ml). CONCLUSIONS: The BNP level may be of value in evaluating severity and prognosis in patients with ALI/ARDS.