title: In-hospital mortality and successful weaning from venoarterial extracorporeal membrane oxygenation: analysis of 5,263 patients using a national inpatient database in Japan.
abstract: BACKGROUND
  The mortality rate of severely ill patients treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO) remains unknown because of differences in patient background, clinical settings, and sample sizes between studies. We determined the in-hospital mortality of VA-ECMO patients and the proportion weaned from VA-ECMO using a national inpatient database in Japan.
  
  
  METHODS
  Patients aged ≥ 19 years who received VA-ECMO during hospitalization for cardiogenic shock, pulmonary embolism, hypothermia, poisoning, or trauma between 1 July 2010 and 31 March 2013 were identified, using The Japanese Diagnosis Procedure Combination national inpatient database.
  
  
  RESULTS
  The primary outcome was in-hospital mortality and the secondary outcome was the proportion weaned from VA-ECMO. A total of 5263 patients received VA-ECMO during the study period. The majority of patients had cardiogenic shock (n = 4,658). The number of patients weaned from VA-ECMO was 3389 (64.4%) and in-hospital mortality after weaning from VA-ECMO was 1994 (37.9%). In-hospital mortality without cardiac arrest in the cardiogenic shock group was significantly lower than that in patients with cardiac arrest (70.5% vs. 77.1%, p <0.001). In the multivariable logistic regression including multiple imputation, higher age and greater or smaller body mass index were significantly associated with in-hospital mortality, whereas hospital volume was not associated with such mortality.
  
  
  CONCLUSIONS
  The present nationwide study showed high mortality rates in patients who received VA-ECMO, and in particular in patients with cardiogenic shock and in patients with cardiac arrest. Weaning from VA-ECMO did not necessarily result in survival. Further studies are warranted to clarify risk-adjusted mortality of VA-ECMO using more detailed data on patient background.
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Aso
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Matsui
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School of Medicine, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fushimi
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. yasunagah-tky@umin.ac.jp.
authors.forename: Hideo
authors.initials: H
authors.lastname: Yasunaga
mesh_terms: D000367:Age Factors; D000368:Aged; D015199:Extracorporeal Membrane Oxygenation / Q000401:mortality*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015996:Survival Rate; D014886:Weaning
keywords: Age factors; Cardiac arrest; Cardiogenic shock; Extracorporeal membrane oxygenation; Mortality