title: The epidemiology of mechanical ventilation use in the United States.
abstract: OBJECTIVE
  Few contemporary population-based data exist about the incidence, patient characteristics, and outcomes of mechanical ventilation in acute care hospitals. We sought to describe the epidemiology of mechanical ventilation use in the United States.
  
  
  METHODS
  Retrospective cohort study using year 2005 hospital discharge records from six states. National projections were generated from age-, race-, and sex-specific rates in the cohort.
  
  
  METHODS
  Nonfederal acute care hospitals.
  
  
  METHODS
  All discharges that included invasive mechanical ventilation identified using International Classification of Diseases, 9th Revision, Clinical Modification procedure codes (96.7x).
  
  
  METHODS
  None.
  
  
  RESULTS
  Of 6,469,674 hospitalizations in the six states, 180,326 (2.8%) received invasive mechanical ventilation. There was a wide age distribution with 52.2% of patients <65 yrs of age. A total of 44.6% had at least one major comorbid condition. The most common comorbidities included diabetes (13.2%) and pulmonary disease (13.2%). Inhospital mortality was 34.5%, and only 30.8% of patients were discharged home from the hospital. Almost all patients received care in urban (73.5%) or suburban (23.6%) hospitals vs. rural hospitals (2.9%). Patients in urban hospitals experienced a higher number of organ dysfunctions, more dialysis and tracheostomies, and higher mortality compared with patients in rural hospitals. Projecting to national estimates, there were 790,257 hospitalizations involving mechanical ventilation in 2005, representing 2.7 episodes of mechanical ventilation per 1000 population. Estimated national costs were $27 billion representing 12% of all hospital costs. Incidence, mortality, and cumulative population costs rose significantly with age.
  
  
  CONCLUSIONS
  Mechanical ventilation use is common and accounts for a disproportionate amount of resource use, particularly in urban hospitals and in elderly patients. Mortality for mechanically ventilated patients is high. Quality improvement and cost-reduction strategies targeted at these patients are warranted.
authors.affiliation: Department of Anesthesiology, Columbia University, New York, NY, USA. hw2125@columbia.edu
authors.forename: Hannah
authors.initials: H
authors.lastname: Wunsch
authors.forename: Walter T
authors.initials: WT
authors.lastname: Linde-Zwirble
authors.forename: Derek C
authors.initials: DC
authors.lastname: Angus
authors.forename: Mary E
authors.initials: ME
authors.lastname: Hartman
authors.forename: Eric B
authors.initials: EB
authors.lastname: Milbrandt
authors.forename: Jeremy M
authors.initials: JM
authors.lastname: Kahn
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003365:Costs and Cost Analysis / Q000706:statistics & numerical data; D005260:Female; D006742:Hospital Bed Capacity / Q000706:statistics & numerical data; D017052:Hospital Mortality; D006780:Hospitals, Rural / Q000706:statistics & numerical data; D006786:Hospitals, Urban / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007223:Infant; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial / Q000191:economics / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D055815:Young Adult