title: Extracorporeal Membrane Oxygenation for 2009 Influenza A(H1N1) Acute Respiratory Distress Syndrome.
abstract: BACKGROUND
  The novel influenza A(H1N1) pandemic affected Australia and New Zealand during the 2009 southern hemisphere winter. It caused an epidemic of critical illness and some patients developed severe acute respiratory distress syndrome (ARDS) and were treated with extracorporeal membrane oxygenation (ECMO).
  
  
  OBJECTIVE
  To describe the characteristics of all patients with 2009 influenza A(H1N1)-associated ARDS treated with ECMO and to report incidence, resource utilization, and patient outcomes.
  
  
  METHODS
  An observational study of all patients (n = 68) with 2009 influenza A(H1N1)-associated ARDS treated with ECMO in 15 intensive care units (ICUs) in Australia and New Zealand between June 1 and August 31, 2009.
  
  
  METHODS
  Incidence, clinical features, degree of pulmonary dysfunction, technical characteristics, duration of ECMO, complications, and survival.
  
  
  RESULTS
  Sixty-eight patients with severe influenza-associated ARDS were treated with ECMO, of whom 61 had either confirmed 2009 influenza A(H1N1) (n = 53) or influenza A not subtyped (n = 8), representing an incidence rate of 2.6 ECMO cases per million population. An additional 133 patients with influenza A received mechanical ventilation but no ECMO in the same ICUs. The 68 patients who received ECMO had a median (interquartile range [IQR]) age of 34.4 (26.6-43.1) years and 34 patients (50%) were men. Before ECMO, patients had severe respiratory failure despite advanced mechanical ventilatory support with a median (IQR) Pao(2)/fraction of inspired oxygen (Fio(2)) ratio of 56 (48-63), positive end-expiratory pressure of 18 (15-20) cm H(2)O, and an acute lung injury score of 3.8 (3.5-4.0). The median (IQR) duration of ECMO support was 10 (7-15) days. At the time of reporting, 48 of the 68 patients (71%; 95% confidence interval [CI], 60%-82%) had survived to ICU discharge, of whom 32 had survived to hospital discharge and 16 remained as hospital inpatients. Fourteen patients (21%; 95% CI, 11%-30%) had died and 6 remained in the ICU, 2 of whom were still receiving ECMO.
  
  
  CONCLUSIONS
  During June to August 2009 in Australia and New Zealand, the ICUs at regional referral centers provided mechanical ventilation for many patients with 2009 influenza A(H1N1)-associated respiratory failure, one-third of whom received ECMO. These ECMO-treated patients were often young adults with severe hypoxemia and had a 21% mortality rate at the end of the study period.
authors.affiliation: FRACP, FJFICM, Intensive Care Unit, Alfred Hospital, Commercial Road, Melbourne, Victoria 3004, Australia. a.davies@alfred.org.au
authors.forename: Andrew
authors.initials: A
authors.lastname: Davies
authors.forename: Daryl
authors.initials: D
authors.lastname: Jones
authors.forename: Michael
authors.initials: M
authors.lastname: Bailey
authors.forename: John
authors.initials: J
authors.lastname: Beca
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.forename: Nikki
authors.initials: N
authors.lastname: Blackwell
authors.forename: Paul
authors.initials: P
authors.lastname: Forrest
authors.forename: David
authors.initials: D
authors.lastname: Gattas
authors.forename: Emily
authors.initials: E
authors.lastname: Granger
authors.forename: Robert
authors.initials: R
authors.lastname: Herkes
authors.forename: Andrew
authors.initials: A
authors.lastname: Jackson
authors.forename: Shay
authors.initials: S
authors.lastname: McGuinness
authors.forename: Priya
authors.initials: P
authors.lastname: Nair
authors.forename: Vincent
authors.initials: V
authors.lastname: Pellegrino
authors.forename: Ville
authors.initials: V
authors.lastname: Pettilä
authors.forename: Brian
authors.initials: B
authors.lastname: Plunkett
authors.forename: Roger
authors.initials: R
authors.lastname: Pye
authors.forename: Paul
authors.initials: P
authors.lastname: Torzillo
authors.forename: Steve
authors.initials: S
authors.lastname: Webb
authors.forename: Michael
authors.initials: M
authors.lastname: Wilson
authors.forename: Marc
authors.initials: M
authors.lastname: Ziegenfuss
mesh_terms: D000328:Adult; D001315:Australia; D015897:Comorbidity; D015199:Extracorporeal Membrane Oxygenation; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000150:complications / Q000401:mortality / Q000628:therapy; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D009520:New Zealand; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000401:mortality / Q000628:therapy; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000209:etiology* / Q000401:mortality / Q000628:therapy*; D016019:Survival Analysis