title: Behavior of B-type natriuretic peptide during mechanical ventilation and spontaneous breathing after extubation.
abstract: BACKGROUND
  The behavior of B-type natriuretic peptide (BNP) is assessed during mechanical ventilation (MV) and spontaneous breathing after extubation in critical patients.
  
  
  METHODS
  Thirty patients admitted in the Intensive Care Unit (ICU) were enrolled. BNP, fluid balance (FB), airway pressure (AP) and dobutamine infusion needing (DP) were registered in three stages: T0, admission to ICU; T1, before extubation; T2, 24 h after extubation.
  
  
  RESULTS
  Patients with congestive heart failure (CHF) had BNP values higher than other patients. The value of BNP during MV was greater than normal in all patients. The cut-off to discriminate patients with heart failure during MV was 286 pgxmL(-1)(sensitivity: 86%; specificity: 90%). The increase of BNP during MV directly correlated with FB and inversely correlated with AP and DP. The plasmatic level of BNP remained higher than normal values 24 h after extubation.
  
  
  CONCLUSIONS
  The underlying disease of an ICU patient seems to play a relevant role for BNP production and is probably linked to different aspects of therapeutic approach required by the patient. Our data suggest a cut-off value of BNP higher than the usual is necessary to discriminate mechanically-ventilated patients without CHF. This study should be repeated with an enlarged population.
authors.affiliation: Azienda Ospedaliero-Universitaria Ospedali Riuniti Umberto I, G. M. Lancisi, G. Salesi, Ancona, Italy.
authors.forename: T
authors.initials: T
authors.lastname: Principi
authors.forename: G
authors.initials: G
authors.lastname: Falzetti
authors.forename: D
authors.initials: D
authors.lastname: Elisei
authors.forename: A
authors.initials: A
authors.lastname: Donati
authors.forename: P
authors.initials: P
authors.lastname: Pelaia
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D048429:Cell Size; D016638:Critical Illness / Q000628:therapy; D004280:Dobutamine / Q000008:administration & dosage / Q000627:therapeutic use; D004417:Dyspnea / Q000097:blood / Q000209:etiology; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D032383:Myocytes, Cardiac / Q000378:metabolism; D020097:Natriuretic Peptide, Brain / Q000097:blood* / Q000378:metabolism; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D012121:Respiration, Artificial; D012680:Sensitivity and Specificity; D015300:Ventilator Weaning; D018487:Ventricular Dysfunction, Left / Q000097:blood / Q000503:physiopathology; D014882:Water-Electrolyte Balance
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D004280:Dobutamine