title: The impact of a "low-intensity" versus "high-intensity" medical intensive care unit on patient outcomes in critically ill veterans.
abstract: OBJECTIVE
  To determine whether a low-intensity versus high-intensity medical intensive care unit (MICU) format in a Veterans Affairs (VA) hospital setting improves patient outcomes, as measured by duration of mechanical ventilation (MV), ventilator-free days (VFDs), and hospital mortality.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Medical intensive care unit at the San Francisco Veterans Affairs Medical Center (SFVAMC).
  
  
  METHODS
  On July 1, 2004, the SFVAMC transitioned from a low-intensity MICU to a high-intensity MICU. All patients admitted to the MICU who required MV for 18 months before (n = 96) and 18 months after (n = 131) the transition were included in the analysis.
  
  
  METHODS
  We prospectively defined the primary outcome measure as the difference in the median duration of MV between groups. Secondary outcomes included VFDs and hospital mortality. Continuous variables were compared using the Wilcoxon rank sum test; dichotomous variables were compared using Fisher exact test.
  
  
  RESULTS
  The low-intensity and high-intensity MICU groups were similar in age, gender, weight, and admitting diagnosis (P > .27 in all cases). Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were 22.0 in the low-intensity era and 20.0 in the high-intensity era (P = .048). Median duration of MV was significantly lower in the high-intensity MICU format compared to the low-intensity MICU format (102 vs 61 hours, P for log-rank test = .0052). After controlling for covariates, there were 4.2 more VFDs in the high-intensity era (95% CI 1.9 to 6.6 days). The high-intensity era was associated with a reduced hospital mortality rate (27% vs 40%) and an adjusted odds ratio of 0.34 (95% CI 0.15 to 0.74).
  
  
  CONCLUSIONS
  For critically ill veterans admitted to an MICU requiring MV, a high-intensity ICU structure is associated with more favorable mechanical ventilatory outcomes and lower mortality.
authors.affiliation: Division of Pulmonary/Critical Care Medicine, UC San Francisco, CA 94143, USA. jon.singer@ucsf.edu
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Singer
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Kohlwes
authors.forename: Stephen
authors.initials: S
authors.lastname: Bent
authors.forename: Leslie
authors.initials: L
authors.lastname: Zimmerman
authors.forename: Mark D
authors.initials: MD
authors.lastname: Eisner
mesh_terms: D000368:Aged; D003422:Critical Care / Q000379:methods*; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D017052:Hospital Mortality; D006787:Hospitals, Veterans; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012495:San Francisco; D016896:Treatment Outcome; D014728:Veterans
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