title: The epidemiology of in-hospital cardiac arrests in Australia and New Zealand.
abstract: BACKGROUND
  The epidemiology of in-hospital cardiac arrests (IHCA) in Australia and New Zealand (ANZ) has not been systematically assessed.
  
  
  OBJECTIVE
  To conduct a systematic review of the frequency, characteristics and outcomes of adult IHCA in ANZ.
  
  
  METHODS
  Medline search for studies published in 1964-2014 using MeSH terms 'arrest AND hospital AND Australia', 'arrest AND hospital AND New Zealand', 'inpatient AND arrest AND Australia' and 'inpatient AND arrest AND New Zealand'.
  
  
  RESULTS
  We screened 934 studies, analysed 50 and included 30. Frequency of IHCA ranged from 1.31 to 6.11 per 1000 admissions in 4 population studies and 0.58 to 4.59 per 1000 in 16 cohort studies. The frequency was 4.11 versus 1.32 per 1000 admissions in hospitals with rapid response system (RRS) compared with those without (odds ratio: 0.32; 95% confidence interval 0.28-0.37; P < 0.001). On aggregate, the initial cardiac rhythm was ventricular tachycardia/fibrillation in 31.4% (range 19.0-48.8%) in 10 studies reporting such data. On aggregate, IHCA were witnessed in 80.2% cases (three studies) and monitored patients in 53.4% cases (four studies). Details of life support were poorly documented. On aggregate, return of spontaneous circulation occurred in 46.0% of patients. Overall, 74.6% (range 59.4-77.5%) died in-hospital but survival was higher among monitored or younger patients, in those with a shockable rhythm, or during working hours.
  
  
  CONCLUSIONS
  IHCA are uncommon in ANZ and three quarters die in-hospital. However, their frequency varies markedly across institutions and may be affected by the presence of RRS. Where reported, the long-term outcomes survivors appear to have acceptable neurological outcomes.
authors: Intensive Care Unit, Western Health, Melbourne, Victoria, Australia.
authors: G
authors: G
authors: Fennessy
authors: Intensive Care Unit, Austin Hospital, Melbourne, Victoria, Australia.
authors: A
authors: A
authors: Hilton
authors: Intensive Care Unit, Austin Hospital, Melbourne, Victoria, Australia.|The University of Melbourne, Austin Hospital, Melbourne, Victoria, Australia.
authors: S
authors: S
authors: Radford
authors: Intensive Care Unit, Austin Hospital, Melbourne, Victoria, Australia.|The University of Melbourne, Austin Hospital, Melbourne, Victoria, Australia.
authors: R
authors: R
authors: Bellomo
authors: Intensive Care Unit, Austin Hospital, Melbourne, Victoria, Australia. Daryl.Jones@austin.org.au.|Monash University, Austin Hospital, Melbourne, Victoria, Australia. Daryl.Jones@austin.org.au.
authors: D
authors: D
authors: Jones
mesh_terms: D000367:Age Factors; D001315:Australia; D016887:Cardiopulmonary Resuscitation; D006323:Heart Arrest / Q000401:mortality* / Q000628:therapy; D017052:Hospital Mortality; D006801:Humans; D008991:Monitoring, Physiologic; D009520:New Zealand; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000453:epidemiology*; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000150:complications* / Q000453:epidemiology*
keywords: cardiac arrest; defibrillation; in-hospital; mortality; rapid response