title: N-terminal-pro-BNP in critically ill patients with acute respiratory failure: a prospective cohort study.
abstract: BACKGROUND
  The aim of this study was to evaluate the prognostic value of plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) in unselected critically ill patients with acute respiratory failure (ARF).
  
  
  METHODS
  Prospective, observational cohort study in 25 intensive care units in Finland. This study included a total of 602 patients with laboratory samples from 958 consecutive patients with ARF treated either with invasive or with non-invasive ventilatory support (the FINNALI study). Plasma NT-pro-BNP samples were drawn after the onset of ventilatory support (day 0) and on the morning of the second day.
  
  
  RESULTS
  The median [interquartile ranges (IQR)] NT-pro-BNP-values were significantly higher at baseline in 90-day non-survivors than the survivors, 4378 pg/ml (1400-13,943 pg/ml) vs. 1052 pg/ml (232-4076 pg/ml), respectively. The median (IQR) NT-pro-BNP values were significantly higher in patients with chronic cardiac disease or cardiac surgery than in non-cardiac patients, 1947 pg/ml (801-4687 pg/ml) vs. 417 pg/ml (153-1735 pg/ml), respectively, if renal function was normal. With deteriorating renal function, the NT-pro-BNP values showed a significant increase. The area under curve for baseline NT-pro-BNP predicting 90-day mortality was moderate: 0.718 (95% confidence interval 0.674-0.761). Baseline NT-pro-BNP over 1765 pg/ml was independently associated with 90-day mortality by logistic regression analysis (P<0.001).
  
  
  CONCLUSIONS
  NT-pro-BNP on admission is commonly elevated and independently associated with 90-day mortality in critically ill ARF patients. However, the routine use of NT-pro-BNP for prognostic purpose does not seem to add value to clinical data in ARF patients.
authors.affiliation: Department of Anaesthesia and Intensive Care Medicine, Division of Surgery, Helsinki University Central Hospital, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Okkonen
authors.forename: M
authors.initials: M
authors.lastname: Varpula
authors.forename: R
authors.initials: R
authors.lastname: Linko
authors.forename: J
authors.initials: J
authors.lastname: Perttilä
authors.forename: T
authors.initials: T
authors.lastname: Varpula
authors.forename: V
authors.initials: V
authors.lastname: Pettilä
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D016638:Critical Illness; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D012131:Respiratory Insufficiency / Q000097:blood* / Q000401:mortality
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain