title: Long term effect of a medical emergency team on cardiac arrests in a teaching hospital.
abstract: BACKGROUND
  It is unknown whether the reported short-term reduction in cardiac arrests associated with the introduction of the medical emergency team (MET) system can be sustained.
  
  
  METHODS
  We conducted a prospective, controlled before-and-after examination of the effect of a MET system on the long-term incidence of cardiac arrests. We included consecutive patients admitted during three study periods: before the introduction of the MET; during the education phase preceding the implementation of the MET; and a period of four years from the implementation of the MET system. Cardiac arrests were identified from a log book of cardiac arrest calls and cross-referenced with case report forms and the intensive care unit admissions database. We measured the number of hospital admissions and MET reviews during each period, performed multivariate logistic regression analysis to identify predictors of mortality following cardiac arrest and studied the correlation between the rate of MET calls with the rate of cardiac arrests.
  
  
  RESULTS
  Before the introduction of the MET system there were 66 cardiac arrests and 16,246 admissions (4.06 cardiac arrests per 1,000 admissions). During the education period, the incidence of cardiac arrests decreased to 2.45 per 1,000 admissions (odds ratio (OR) for cardiac arrest 0.60; 95% confidence interval (CI) 0.43-0.86; p = 0.004). After the implementation of the MET system, the incidence of cardiac arrests further decreased to 1.90 per 1,000 admissions (OR for cardiac arrest 0.47; 95% CI 0.35-0.62; p < 0.0001). There was an inverse correlation between the number of MET calls in each calendar year and the number of cardiac arrests for the same year (r2 = 0.84; p = 0.01), with 17 MET calls being associated with one less cardiac arrest. Male gender (OR 2.88; 95% CI 1.34-6.19) and an initial rhythm of either asystole (OR 7.58; 95% CI 3.15-18.25; p < 0.0001) or pulseless electrical activity (OR 4.09; 95% CI 1.59-10.51; p = 0.003) predicted an increased risk of death.
  
  
  CONCLUSIONS
  Introduction of a MET system into a teaching hospital was associated with a sustained and progressive reduction in cardiac arrests over a four year period. Our findings show sustainability and suggest that, for every 17 MET calls, one cardiac arrest might be prevented.
authors.affiliation: Department of Intensive Care, Alfred Hospital, Commercial Road, Prahran, Melbourne, Victoria 3181, Australia.
authors.forename: Daryl
authors.initials: D
authors.lastname: Jones
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.forename: Samantha
authors.initials: S
authors.lastname: Bates
authors.forename: Stephen
authors.initials: S
authors.lastname: Warrillow
authors.forename: Donna
authors.initials: D
authors.lastname: Goldsmith
authors.forename: Graeme
authors.initials: G
authors.lastname: Hart
authors.forename: Helen
authors.initials: H
authors.lastname: Opdam
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Gutteridge
mesh_terms: D000368:Aged; D016887:Cardiopulmonary Resuscitation / Q000193:education / Q000706:statistics & numerical data*; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006323:Heart Arrest / Q000453:epidemiology* / Q000628:therapy*; D006784:Hospitals, Teaching / Q000458:organization & administration / Q000706:statistics & numerical data*; D006801:Humans; D015994:Incidence; D007318:Inservice Training / Q000706:statistics & numerical data; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D015999:Multivariate Analysis; D010043:Outcome and Process Assessment, Health Care; D011446:Prospective Studies; D016019:Survival Analysis; D014739:Victoria / Q000453:epidemiology