title: The inflammatory response after out-of-hospital cardiac arrest is not modified by targeted temperature management at 33 °C or 36 °C.
abstract: OBJECTIVE
  Survivors after cardiac arrest (CA) exhibits a systemic inflammatory response as part of post-cardiac arrest syndrome (PCAS). We investigated the association between systemic inflammation and severity of PCAS and whether level of targeted temperature management (TTM) modifies level of the inflammatory response.
  
  
  METHODS
  We studied 169 patients included at a single center in the TTM-trial, randomly assigned to TTM at 33 °C or 36 °C for 24 h. Plasma samples were analyzed for inflammatory markers including interleukin (IL) IL-1β,IL-4,IL-6,IL-10, tumor necrosis factor-α (TNF-α), C-reactive protein (CRP) and procalcitonin (PCT) at randomization and 24, 48 and 72 h after CA. Severity of PCAS was assessed by Sequential Organ Failure Assessment (SOFA) score.
  
  
  RESULTS
  Plasma levels of both IL-6 and IL-10 determined at randomization correlated with severity of PCAS at day 2 (r=0.36 and r=0.27, p<0.001) and day 3 (r=0.32 and r=0.22, p<0.001). IL-6 at randomization was an independent predictor of severity of PCAS at day 2 (p=0.003) and day 3 (p<0.0001) and was a significantly stronger predictor of severity of PCAS at day 3 compared to CRP (p=0.04) and PCT (p=0.03). Level of TTM did not modify level of the inflammatory markers IL-1β, IL-6, TNF-α, IL-4, IL-10, CRP and PCT, (p=NS for each inflammatory marker).
  
  
  CONCLUSIONS
  Level of inflammatory response was associated with severity of PCAS with IL-6 being consistently and more strongly associated with severity of PCAS than the inflammatory markers CRP and PCT. The systemic inflammatory response after CA was not modified by TTM at 33 °C or 36 °C.
authors.affiliation: Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. Electronic address: jbj@dadlnet.dk.
authors.forename: John
authors.initials: J
authors.lastname: Bro-Jeppesen
authors.affiliation: Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Kjaergaard
authors.affiliation: Department of Cardiothoracic Anaesthesia, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Wanscher
authors.affiliation: Department of Anesthesia and Intensive Care, Lund University, Helsingborg Hospital, Helsingborg, Sweden.
authors.forename: Niklas
authors.initials: N
authors.lastname: Nielsen
authors.affiliation: Department of Anesthesia and Intensive Care, Lund University, Skåne University Hospital, Lund, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Friberg
authors.affiliation: The Medical Research Laboratory, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Bjerre
authors.affiliation: Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Hassager
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001774:Blood Chemical Analysis; D016887:Cardiopulmonary Resuscitation / Q000379:methods* / Q000401:mortality; D002423:Cause of Death; D003422:Critical Care / Q000379:methods; D016207:Cytokines / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects / Q000379:methods*; D018836:Inflammation Mediators / Q000097:blood; D007362:Intensive Care Units; D007378:Interleukins / Q000097:blood; D053208:Kaplan-Meier Estimate; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D058687:Out-of-Hospital Cardiac Arrest / Q000097:blood / Q000401:mortality / Q000628:therapy*; D016037:Single-Blind Method; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D018746:Systemic Inflammatory Response Syndrome / Q000401:mortality / Q000503:physiopathology*; D013696:Temperature
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D007378:Interleukins
keywords: Cardiac arrest; Cytokines; Hypothermia; Inflammation; Post-cardiac arrest syndrome