title: Trajectories of the averaged abbreviated Vitalpac early warning score (AbEWS) and clinical course of 44,531 consecutive admissions hospitalized for acute medical illness.
abstract: BACKGROUND
  It is not known how often, to what extent and over what time frame any early warning scores change, and what the implications of these changes are.
  
  
  METHODS
  Thunder Bay Regional Health Sciences Center, Ontario, Canada.
  
  
  METHODS
  The averaged vital signs measured over different time periods of 44,531 consecutive acutely ill medical admissions were determined and then combined to calculate the averaged abbreviated version of the Vitalpac early warning score (AbEWS) during each time period examined.
  
  
  RESULTS
  18% of all in-hospital deaths within 30 days are in patients with a low AbEWS on admission. Those admitted with a low AbEWS are more likely to increase their score and those admitted with a high score are more likely to lower it. Paradoxically, patients who have an averaged score over the first 6h in hospital that is lower than on admission have increased in-hospital mortality. Thereafter patients with an increase in the averaged score have almost twice the mortality of those with a decreased score. 4.7% of patients have a low averaged score on the day they die.
  
  
  CONCLUSIONS
  AbEWS, without clinical judgment, cannot be used to detect those patients who do not need to be admitted to hospital or are suitable for discharge. A period of observation of at least 12h is required before the trajectory of AbEWS is of prognostic value, and any "improvement" that occurs before this time may be illusory.
authors.affiliation: Dundalk Institute of Technology, Dundalk, Ireland.
authors.forename: Alan
authors.initials: A
authors.lastname: Murray
authors.affiliation: Thunder Bay Regional Health Sciences Center, Thunder Bay, Ontario, Canada. Electronic address: jgkellett@eircom.net.
authors.forename: John
authors.initials: J
authors.lastname: Kellett
authors.affiliation: Department of Mathematical Sciences, Lakehead University, Thunder Bay, Ontario, Canada.
authors.forename: Wendy
authors.initials: W
authors.lastname: Huang
authors.affiliation: Health Information Systems Research Center, University College Cork, Ireland.
authors.forename: Simon
authors.initials: S
authors.lastname: Woodworth
authors.affiliation: Department of Mathematical Sciences, Lakehead University, Thunder Bay, Ontario, Canada.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
mesh_terms: D000208:Acute Disease / Q000401:mortality* / Q000628:therapy; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006305:Health Status Indicators; D017052:Hospital Mortality; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D013997:Time Factors; D055986:Vital Signs
keywords: Acute medical units; Early warning scores; Outcomes; Prognosis