title: Impact of noninvasive ventilation (NIV) trial for various types of acute respiratory failure in the emergency department; decreased mortality and use of the ICU.
abstract: BACKGROUND
  Trial of noninvasive ventilation (NIV) in the emergency department (ED) for heterogeneous acute respiratory failure (ARF) has been optional and its clinical benefit unclear.
  
  
  METHODS
  We conducted a retrospective cohort study comparing between two periods, October 2001-September 2003 and October 2004-September 2006, i.e., before and after adopting an NIV-trial strategy in which NIV was applied in the ED to any noncontraindicated ARF patients needing ventilatory support and was then continued in the intermediate-care-unit. During these two periods, we retrieved cases of ARF treated either invasively or with NIV, and compared the patients' in-hospital mortalities and the length of ICU and intermediate-care-unit stay.
  
  
  RESULTS
  Compared were 73 (invasive 56, NIV 17) and 125 cases (invasive 31, NIV 94) retrieved from 271 and 415 emergent admissions with proper pulmonary etiologies for mechanical ventilation, respectively. Of their respiratory failures, type (hypercapnic/non-hypercapnic, 0.97 vs. 0.98) and severity (pH 7.23 vs. 7.21 for hypercapnic; PaO(2)/FiO(2) 133 vs. 137 for non-hypercapnic) were similar, and the rate of predisposing etiologies was not significantly different. However, excluding those with recurrent aspiration pneumonia for whom NIV was mostly used as "ceiling" treatment, significant reductions in both overall in-hospital mortality (38%-19%, risk ratio 0.51, 95% CI 0.31-0.84), and median length of ICU and intermediate-care-unit stay (12 vs. 5 days, P<0.0001) were found.
  
  
  CONCLUSIONS
  NIV-trial in the ED for all possible patients with ARF of pulmonary etiologies, excluding those with recurrent aspiration pneumonia, may reduce overall in-hospital mortality and ICU stays.
authors.affiliation: Department of Respiratory Medicine, Kobe City Medical Center General Hospital, 4-6 Minatojima-Nakamachi, Chuo-ku, Kobe, 650-0046, Japan. ktomii@kcgh.gr.jp
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tomii
authors.forename: Ryutaro
authors.initials: R
authors.lastname: Seo
authors.forename: Ryo
authors.initials: R
authors.lastname: Tachikawa
authors.forename: Yuka
authors.initials: Y
authors.lastname: Harada
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Murase
authors.forename: Reiko
authors.initials: R
authors.lastname: Kaji
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Takeshima
authors.forename: Michio
authors.initials: M
authors.lastname: Hayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishimura
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000208:Acute Disease; D000368:Aged; D004630:Emergencies; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D007380:Intermediate Care Facilities; D053208:Kaplan-Meier Estimate; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial / Q000379:methods*; D012131:Respiratory Insufficiency / Q000401:mortality / Q000628:therapy*; D012189:Retrospective Studies; D012306:Risk