title: Use of intensive care, mechanical ventilation, both, or neither by patients with acute lung injury.
abstract: OBJECTIVE
  Reports of acute lung injury and acute respiratory distress syndrome have generally been restricted to mechanically ventilated intensive care unit patients, creating an incomplete picture of the epidemiologies of the syndromes. We sought to determine the incidence and outcomes of acute lung injury and acute respiratory distress syndromes throughout an entire hospital population.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  A Department of Veterans Affairs medical center.
  
  
  METHODS
  All patients satisfying criteria for acute lung injury or acute respiratory distress syndrome during a 2-yr period.
  
  
  METHODS
  None.
  
  
  RESULTS
  There were 11,465 acute medical and surgical admissions during the study period; 156 patients had acute lung injury or acute respiratory distress syndrome. Only 74 (47%) were invasively ventilated in an intensive care unit for acute lung injury. Another 15 (10%) patients were ventilated for other reasons, 41 (26%) were admitted to an intensive care unit at approximately the time of acute lung injury onset but were not invasively ventilated, and 26 (17%) were managed with neither invasive ventilation nor admission to an intensive care unit. Four-week mortality differed by group (p = .023), ranging from 22% among those managed in an intensive care unit without invasive ventilation to 50% among those ventilated for acute lung injury or acute respiratory distress syndrome. By 2 yrs, differences in survival between groups were no longer significant. Notably, only 53 (34%) patients would have been eligible for widely cited acute lung injury intervention trials. Ten patients had a second episode of acute lung injury during the study period, equating to a 16%-per-year risk of recurrence.
  
  
  CONCLUSIONS
  Acute lung injury and acute respiratory distress syndrome studies restricted to patients mechanically ventilated in intensive care units substantially underestimate the incidence of the syndromes. Nonventilated patients and those cared for outside of intensive care units may still be at substantial risk for death. Further characterization of previously overlooked acute lung injury and acute respiratory distress syndrome patients may suggest new therapeutic opportunities.
authors.affiliation: University of Miami, Miller School of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Miami, Florida, USA.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Cely
authors.forename: Julian T
authors.initials: JT
authors.lastname: Rojas
authors.forename: Diego A
authors.initials: DA
authors.lastname: Maldonado
authors.forename: Roland M H
authors.initials: RM
authors.lastname: Schein
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Quartin
mesh_terms: D055371:Acute Lung Injury / Q000401:mortality / Q000628:therapy*; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003422:Critical Care; D005260:Female; D006787:Hospitals, Veterans / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D012008:Recurrence; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000401:mortality / Q000628:therapy; D012189:Retrospective Studies; D016896:Treatment Outcome