title: Patient monitoring and the timing of cardiac arrests and medical emergency team calls in a teaching hospital.
abstract: OBJECTIVE
  To describe the timing of cardiac arrest detection in relation to episodes of Medical Emergency Team (MET) review and routine nursing observations.
  
  
  METHODS
  Retrospective observational study in a university-affiliated hospital.
  
  
  METHODS
  279 cardiac arrests involving ward patients
  
  
  RESULTS
  Cardiac arrests were allocated to one of 24 1-h intervals (24:00-00:59, 01:00-01:59, etc.). The actual hourly rate of cardiac arrests was related to the expected average hourly rate. Peak levels of cardiac arrest detection occurred during times of routine overnight nursing clinical observations between 02:00 and 03:00 (OR 3.06) and 06:00-07:00 (OR 1.95). The lowest level of cardiac arrest detection occurred between 20:00 and 21:00 (OR 0.42). After introduction of the MET there were 162 cardiac arrests, 28% of which occurred shortly after an initial MET call. The odds ratio for risk of cardiac arrest during periods of lowest MET activation (24:00-08:00) when compared with periods of highest MET activation (16:00-24:00) was 2.26.
  
  
  CONCLUSIONS
  Cardiac arrest detection in our hospital is episodic with peak levels corresponding to periods of overnight routine nursing observations following a period when patient review is likely to be low. After the introduction of the MET there was an inverse link between detection of cardiac arrests and levels of MET activation over the 24-h period. Increased overnight utilization and earlier MET activation may further reduce the incidence of cardiac arrests at our hospital.
authors.affiliation: Intensive Care, Alfred Hospital, Monash University, Melbourne, 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
mesh_terms: D016009:Chi-Square Distribution; D002940:Circadian Rhythm; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D006323:Heart Arrest / Q000175:diagnosis*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data*; D006801:Humans; D008991:Monitoring, Physiologic / Q000379:methods*; D017063:Outcome Assessment, Health Care; D012189:Retrospective Studies; D013997:Time Factors