title: Targeted temperature management processes and outcomes after out-of-hospital cardiac arrest: an observational cohort study*.
abstract: OBJECTIVE
  Targeted temperature management has been shown to improve survival with good neurological outcome in patients after out-of-hospital cardiac arrest. The optimal approach to inducing and maintaining targeted temperature management, however, remains uncertain. The objective of this study was to evaluate these processes of care with survival and neurological function in patients after out-of-hospital cardiac arrest.
  
  
  METHODS
  An observational cohort study evaluating the association of targeted temperature management processes with survival and neurological function using bivariate and generalized estimating equation analyses.
  
  
  METHODS
  Thirty-two tertiary and community hospitals in eight urban and rural regions of southern Ontario, Canada.
  
  
  METHODS
  Consecutive adult (≥ 18 yr) patients admitted between November 1, 2007, and January 31, 2012, and who were treated with targeted temperature management following nontraumatic out-of-hospital cardiac arrest.
  
  
  METHODS
  Evaluate the association of targeted temperature management processes with survival and neurologic function using bivariate and generalized estimating equation analyses.
  
  
  RESULTS
  There were 5,770 consecutive out-of-hospital cardiac arrest patients, of whom 747 (12.9%) were eligible and received targeted temperature management. Among patients with available outcome data, 365 of 738 (49.5%) survived to hospital discharge and 241 of 675 (35.7%) had good neurological outcomes. After adjusting for the Utstein variables, a higher temperature prior to initiation of targeted temperature management was associated with improved neurological outcomes (odds ratio, 1.27 per °C; 95% CI, 1.08-1.50; p = 0.004) and survival (odds ratio, 1.26 per °C; 95% CI, 1.09-1.46; p = 0.002). A slower rate of cooling was associated with improved neurological outcomes (odds ratio, 0.74 per °C/hr; 95% CI, 0.57-0.97; p = 0.03) and survival (odds ratio, 0.73 per °C/hr; 95% CI, 0.54-1.00; p = 0.049).
  
  
  CONCLUSIONS
  A higher baseline temperature prior to initiation of targeted temperature management and a slower rate of cooling were associated with improved survival and neurological outcomes. This may reflect a complex relationship between the approach to targeted temperature management and the extent of underlying brain injury causing impaired thermoregulation in out-of-hospital cardiac arrest patients.
authors.affiliation: 1Rescu, Li Ka Shing Knowledge Institute of St. Michael's Hospital, Toronto, ON, Canada. 2Division of Emergency Medicine, Department of Medicine, University of Toronto, Toronto, ON, Canada. 3Institute for Clinical Evaluative Sciences, Sunnybrook Research Institute, Toronto, ON, Canada. 4Interdepartmental Division of Critical Care, Department of Medicine, University of Toronto, Toronto, ON, Canada. 5Department of Critical Care Medicine, Sunnybrook Health Sciences Centre, Toronto, ON, Canada. 6Division of Cardiology, Department of Medicine, University of Toronto, Toronto, ON, Canada. 7Department of Emergency Medicine, Queen's University, Kingston, ON, Canada.
authors.forename: Steve
authors.initials: S
authors.lastname: Lin
authors.forename: Damon C
authors.initials: DC
authors.lastname: Scales
authors.forename: Paul
authors.initials: P
authors.lastname: Dorian
authors.forename: Alexander
authors.initials: A
authors.lastname: Kiss
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Common
authors.forename: Steven C
authors.initials: SC
authors.lastname: Brooks
authors.forename: Shaun G
authors.initials: SG
authors.lastname: Goodman
authors.forename: Justin D
authors.initials: JD
authors.lastname: Salciccioli
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Morrison
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000453:epidemiology; D001831:Body Temperature; D015331:Cohort Studies; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009864:Ontario; D058687:Out-of-Hospital Cardiac Arrest / Q000453:epidemiology / Q000628:therapy*; D012737:Sex Factors; D013997:Time Factors