title: Epidemiology, Patterns of Care, and Mortality for Patients With Acute Respiratory Distress Syndrome in Intensive Care Units in 50 Countries.
abstract: OBJECTIVE
  Limited information exists about the epidemiology, recognition, management, and outcomes of patients with the acute respiratory distress syndrome (ARDS).
  
  
  OBJECTIVE
  To evaluate intensive care unit (ICU) incidence and outcome of ARDS and to assess clinician recognition, ventilation management, and use of adjuncts-for example prone positioning-in routine clinical practice for patients fulfilling the ARDS Berlin Definition.
  
  
  METHODS
  The Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) was an international, multicenter, prospective cohort study of patients undergoing invasive or noninvasive ventilation, conducted during 4 consecutive weeks in the winter of 2014 in a convenience sample of 459 ICUs from 50 countries across 5 continents.
  
  
  METHODS
  Acute respiratory distress syndrome.
  
  
  METHODS
  The primary outcome was ICU incidence of ARDS. Secondary outcomes included assessment of clinician recognition of ARDS, the application of ventilatory management, the use of adjunctive interventions in routine clinical practice, and clinical outcomes from ARDS.
  
  
  RESULTS
  Of 29,144 patients admitted to participating ICUs, 3022 (10.4%) fulfilled ARDS criteria. Of these, 2377 patients developed ARDS in the first 48 hours and whose respiratory failure was managed with invasive mechanical ventilation. The period prevalence of mild ARDS was 30.0% (95% CI, 28.2%-31.9%); of moderate ARDS, 46.6% (95% CI, 44.5%-48.6%); and of severe ARDS, 23.4% (95% CI, 21.7%-25.2%). ARDS represented 0.42 cases per ICU bed over 4 weeks and represented 10.4% (95% CI, 10.0%-10.7%) of ICU admissions and 23.4% of patients requiring mechanical ventilation. Clinical recognition of ARDS ranged from 51.3% (95% CI, 47.5%-55.0%) in mild to 78.5% (95% CI, 74.8%-81.8%) in severe ARDS. Less than two-thirds of patients with ARDS received a tidal volume 8 of mL/kg or less of predicted body weight. Plateau pressure was measured in 40.1% (95% CI, 38.2-42.1), whereas 82.6% (95% CI, 81.0%-84.1%) received a positive end-expository pressure (PEEP) of less than 12 cm H2O. Prone positioning was used in 16.3% (95% CI, 13.7%-19.2%) of patients with severe ARDS. Clinician recognition of ARDS was associated with higher PEEP, greater use of neuromuscular blockade, and prone positioning. Hospital mortality was 34.9% (95% CI, 31.4%-38.5%) for those with mild, 40.3% (95% CI, 37.4%-43.3%) for those with moderate, and 46.1% (95% CI, 41.9%-50.4%) for those with severe ARDS.
  
  
  CONCLUSIONS
  Among ICUs in 50 countries, the period prevalence of ARDS was 10.4% of ICU admissions. This syndrome appeared to be underrecognized and undertreated and associated with a high mortality rate. These findings indicate the potential for improvement in the management of patients with ARDS.
  
  
  BACKGROUND
  clinicaltrials.gov Identifier: NCT02010073.
authors.affiliation: School of Medicine and Surgery, University of Milan-Bicocca, Monza, Italy2Department of Emergency and Intensive Care, San Gerardo Hospital, Monza, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Bellani
authors.affiliation: Departments of Anesthesia and Critical Care Medicine, Keenan Research Centre for Biomedical Science, St Michael's Hospital4Departments of Anesthesia, Physiology and Interdepartmental division of Critical Care Medicine, University of Toronto, Canada.
authors.forename: John G
authors.initials: JG
authors.lastname: Laffey
authors.affiliation: AP-HP, Hôpital Tenon, Unité de Réanimation médico-chirurgicale, Pôle Thorax Voies aériennes, Groupe hospitalier des Hôpitaux Universitaires de l'Est Parisien, Paris, France6UMR 1153, Inserm, Sorbonne Paris Cité, ECSTRA Team, Université Paris Diderot, Pari.
authors.forename: Tài
authors.initials: T
authors.lastname: Pham
authors.affiliation: Department of Medicine, University Health Network and Mount Sinai Hospital9Interdepartmental Division of Critical Care Medicine and Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada.
authors.forename: Eddy
authors.initials: E
authors.lastname: Fan
authors.affiliation: Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Canada11Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada.
authors.forename: Laurent
authors.initials: L
authors.lastname: Brochard
authors.affiliation: Hospital Universitario de Getafe, CIBER de Enfermedades Respiratorias, Madrid, Spain.
authors.forename: Andres
authors.initials: A
authors.lastname: Esteban
authors.affiliation: Istituto di Anestesia e Rianimazione, Università degli Studi di Milano, Ospedale Maggiore, Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Gattinoni
authors.affiliation: Intensive Care Unit, Canberra Hospital, and Australian National University, Canberra, Australia.
authors.forename: Frank
authors.initials: F
authors.lastname: van Haren
authors.affiliation: Section of Anesthesiology and Intensive Care, Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Larsson
authors.affiliation: Centre for Experimental Medicine, Queen's University of Belfast, Belfast, Northern Ireland17Wellcome-Wolfson Institute for Experimental Medicine, Belfast, Northern Ireland18Regional Intensive Care Unit, Royal Victoria Hospital, Grosvenor Road, Belfast, No.
authors.forename: Daniel F
authors.initials: DF
authors.lastname: McAuley
authors.affiliation: SAPIENZA Università di ROMA, Dipartimento di Anestesia e Rianimazione, Policlinico Umberto I, Viale del Policlinico 155, 00161 Roma, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ranieri
authors.affiliation: Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Canada21Program in Trauma, Emergency and Critical Care, Sunnybrook Health Sciences Center, Toronto, Canada.
authors.forename: Gordon
authors.initials: G
authors.lastname: Rubenfeld
authors.affiliation: Division of Pulmonary and Critical Care Unit, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston.
authors.forename: B Taylor
authors.initials: BT
authors.lastname: Thompson
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University of Leipzig, Liebigstr. 20, D-04103 Leipzig, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Wrigge
authors.affiliation: Keenan Research Center at the Li Ka Shing Knowledge Institute of St Michael's Hospital, the Interdepartmental Division of Critical Care Medicine, and the Department of Medicine, University of Toronto, Toronto, Canada.
authors.forename: Arthur S
authors.initials: AS
authors.lastname: Slutsky
authors.affiliation: Istituto di Anestesia e Rianimazione, Università degli Studi di Milano, Ospedale Maggiore, Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pesenti
mesh_terms: D000465:Algorithms; D005260:Female; D014943:Global Health / Q000706:statistics & numerical data*; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D019148:Neuromuscular Blockade / Q000379:methods / Q000706:statistics & numerical data; D063305:Organ Dysfunction Scores; D056888:Patient Positioning; D011175:Positive-Pressure Respiration / Q000379:methods* / Q000706:statistics & numerical data; D015995:Prevalence; D016684:Prone Position; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy*; D012720:Severity of Illness Index; D016896:Treatment Outcome