title: Serious adverse events in a hospital using early warning score - what went wrong?
abstract: OBJECTIVE
  To evaluate the performance of a new early warning score (EWS) system by reviewing all serious adverse events in our hospital over a 6-month time period.
  
  
  METHODS
  All incidents of unexpected death (UD), cardiac arrest (CA) and unanticipated intensive care unit admission(UICU) of adult patients on general wards were reviewed to see if the escalation protocol that is part of the EWS system was followed in the 24h preceding the event, and if not where in the chain of events failure occurred.
  
  
  RESULTS
  We found 77 UICU and 67 cases of the combined outcome (CO) of CA and UD. At least two full sets of EWS were recorded in 87, 94 and 75% of UICU, CA and UD. Patients were monitored according to the escalation protocol in 13, 31 and 13% of UICU, CA and UD. Nurses escalated care and contacted physicians in 64% and 60% of events of UICU and the corresponding proportions for CO were 58% and 55%. On call physicians provided adequate care in 49% of cases of UICU and 29% of cases of the CO. Senior staff was involved according to protocol in 53% and 36% of cases of UICU and CO, respectively.
  
  
  CONCLUSIONS
  Poor compliance with the escalation protocol was commonly found when serious adverse events occurred but level of care provided by physicians was also a problem in a hospital with implemented early warning system. This information may prove useful in improving performance of EWS systems.
authors.affiliation: Department of Anaesthesia and Intensive Care, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 24, 2400 Copenhagen NV, Denmark. Electronic address: john.asger.petersen@regionh.dk.
authors.forename: John Asger
authors.initials: JA
authors.lastname: Petersen
authors.affiliation: Department of Anaesthesia and Intensive Care, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 24, 2400 Copenhagen NV, Denmark.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Mackel
authors.affiliation: Board of Directors Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 24, 2400 Copenhagen NV, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Antonsen
authors.affiliation: Center of Head and Orthopedics, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark.
authors.forename: Lars S
authors.initials: LS
authors.lastname: Rasmussen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003718:Denmark / Q000453:epidemiology; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000175:diagnosis / Q000401:mortality*; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*
keywords: Early warning score; In-hospital cardiac arrest; Medical emergency team; Rapid response system