title: von Willebrand factor antigen is an independent marker of poor outcome in patients with early acute lung injury.
abstract: OBJECTIVE
  The primary objective of this study was to test the hypothesis that the degree of systemic endothelial activation, as measured by the release of von Willebrand factor antigen into the circulation and pulmonary edema fluid, is an important determinant of outcome from acute lung injury and acute respiratory distress syndrome.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  Intensive care unit patients in a tertiary university hospital and a university-affiliated city hospital.
  
  
  METHODS
  Fifty-one intubated, mechanically ventilated intensive care unit patients with acute lung injury or acute respiratory distress syndrome as defined by the North American European Consensus Conference definitions.
  
  
  METHODS
  Undiluted pulmonary edema fluid and plasma were collected within 1 hr of endotracheal intubation in all patients.
  
  
  METHODS
  von Willebrand factor antigen concentrations and protein concentration were measured in pulmonary edema fluid and in plasma.
  
  
  RESULTS
  At the time of intubation, median plasma von Willebrand factor antigen was 251%, two-fold higher than the median pulmonary edema fluid von Willebrand factor antigen of 130%. Median edema fluid and plasma von Willebrand factor antigen concentrations were significantly higher in patients who did not survive hospitalization. Plasma von Willebrand factor antigen was also higher in those patients who had a longer duration of mechanical ventilation (as measured by ventilator-free days). Plasma von Willebrand factor antigen was also significantly higher in patients with sepsis and two or more organ system failures. According to stepwise logistic regression analysis, plasma von Willebrand factor antigen was independently associated with in hospital death. The positive predictive value for death if the plasma von Willebrand factor antigen concentration was >450% was 83%. A plasma von Willebrand factor antigen concentration of >450% previously has been shown to predict the development of acute respiratory distress syndrome.
  
  
  CONCLUSIONS
  These findings suggest that the degree of systemic endothelial activation and injury at the onset of acute lung injury is an important determinant of the outcome from acute lung injury.
authors.affiliation: Department of Medicine, University of California San Francisco, San Francisco, CA 94143, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Ware
authors.forename: E R
authors.initials: ER
authors.lastname: Conner
authors.forename: M A
authors.initials: MA
authors.lastname: Matthay
mesh_terms: D000941:Antigens / Q000378:metabolism*; D015415:Biomarkers; D002140:California / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D011654:Pulmonary Edema / Q000378:metabolism; D012128:Respiratory Distress Syndrome / Q000175:diagnosis* / Q000378:metabolism / Q000401:mortality; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D014841:von Willebrand Factor / Q000276:immunology*
chemical_list: D000941:Antigens; D015415:Biomarkers; C029417:Von Willebrand antigen; D014841:von Willebrand Factor