title: Time to start of cardiopulmonary resuscitation and the effect of target temperature management at 33°C and 36°C.
abstract: BACKGROUND
  The optimal temperature during targeted temperature management (TTM) for comatose patients resuscitated from out-of-hospital cardiac arrest is unknown. It has been hypothesized that patients with long no-flow times, for example those without bystander CPR would have the most to gain from temperature management at lower temperatures.
  
  
  METHODS
  We analysed data from an international clinical trial randomizing cardiac arrest patients to targeted temperature management at 33°C and 36°C for an interaction between no-flow time and intervention group, with neurological function at six months after cardiac arrest as the primary outcome. A cerebral performance category (CPC) score of 1 or 2 was considered a good outcome.
  
  
  RESULTS
  No-flow time (min) was associated with poor neurological outcome (OR 1.13, 95% confidence interval 1.06-1.20, p<0.001). There was no statistically significant interaction between no flow-time and intervention group (p=0.11), which may imply that the non-superior effect of 33°C was consistent for all no-flow times. Bystander CPR was not independently associated with neurological function.
  
  
  CONCLUSIONS
  TTM at 33°C compared to 36°C was not associated with an increased probability of a good neurological function for patients with longer no-flow times.
authors.affiliation: Department of Intensive and Perioperative Care, Skåne University Hospital, Lund, Sweden; Department of Clinical Sciences, Lund University, Lund, Sweden. Electronic address: josef.dankiewicz@gmail.com.
authors.forename: Josef
authors.initials: J
authors.lastname: Dankiewicz
authors.affiliation: Department of Intensive and Perioperative Care, Skåne University Hospital, Lund, Sweden; Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Friberg
authors.affiliation: 2nd Department of Cardiovascular Internal Medicine, First Medical Faculty, Charles University, Prague and General Teaching Hospital of Prague, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Bělohlávek
authors.affiliation: Department of Intensive Care, Royal Berkshire Hospital, Reading, United Kingdom.
authors.forename: Andrew
authors.initials: A
authors.lastname: Walden
authors.affiliation: Department of Cardiology, The Heart Centre, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Hassager
authors.affiliation: Department of Intensive and Perioperative Care, Skåne University Hospital, Lund, Sweden; Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Tobias
authors.initials: T
authors.lastname: Cronberg
authors.affiliation: Department of Intensive and Perioperative Care, Skåne University Hospital, Lund, Sweden; Department of Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: David
authors.initials: D
authors.lastname: Erlinge
authors.affiliation: Department of Intensive Care, Geneva University Hospital, Geneva, Switzerland.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Gasche
authors.affiliation: Department of Anesthesiology, Rikshospitalet, Oslo University Hospital, Oslo, Norway.
authors.forename: Jan
authors.initials: J
authors.lastname: Hovdenes
authors.affiliation: Department of Intensive Care, Academic Medical Centre, Amsterdam, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Horn
authors.affiliation: Department of Cardiology, The Heart Centre, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Kjaergaard
authors.affiliation: Department of Intensive Care, Leeuwarden Hospital, Leeuwarden, The Netherlands.
authors.forename: Michael
authors.initials: M
authors.lastname: Kuiper
authors.affiliation: Department of Intensive Care, Santa Maria degli Ángeli, Pordenone, Italy.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pellis
authors.affiliation: Department of Anesthesiology and Intensive Care, Centre Hospitalier de Luxembourg, Luxembourg City, Luxembourg.
authors.forename: Pascal
authors.initials: P
authors.lastname: Stammet
authors.affiliation: The Heart Centre, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Wanscher
authors.affiliation: Copenhagen Trial Unit, Centre of Clinical Intervention Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
authors.forename: Jørn
authors.initials: J
authors.lastname: Wetterslev
authors.affiliation: Adult Critical Care, University Hospital of Wales, Cardiff, United Kingdom.
authors.forename: Matthew
authors.initials: M
authors.lastname: Wise
authors.affiliation: Department of Intensive Care, Liverpool Hospital, Sydney, NSW, Australia.
authors.forename: Anders
authors.initials: A
authors.lastname: Åneman
authors.affiliation: Department of Clinical Sciences, Lund University, Lund, Sweden; Department of Anesthesiology and Intensive Care, Helsingborg Hospital, Helsingborg, Sweden.
authors.forename: Niklas
authors.initials: N
authors.lastname: Nielsen
mesh_terms: D000368:Aged; D001831:Body Temperature; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy*; D013997:Time Factors
keywords: Cardiac arrest; Neurological function; Targeted temperature management