title: Is hypothermia after cardiac arrest effective in both shockable and nonshockable patients?: insights from a large registry.
abstract: BACKGROUND
  Although the level of evidence of improvement is significant in cardiac arrest patients resuscitated from a shockable rhythm (ventricular fibrillation or pulseless ventricular tachycardia [VF/Vt]), the use of therapeutic mild hypothermia (TMH) is more controversial in nonshockable patients (pulseless electric activity or asystole [PEA/asystole]). We therefore assessed the prognostic value of hypothermia for neurological outcome at hospital discharge according to first-recorded cardiac rhythm in a large cohort.
  
  
  RESULTS
  Between January 2000 and December 2009, data from 1145 consecutive out-of-hospital cardiac arrest patients in whom a successful resuscitation had been achieved were prospectively collected. The association of TMH with a good neurological outcome at hospital discharge (cerebral performance categories level 1 or 2) was quantified by logistic regression analysis. TMH was induced in 457/708 patients (65%) in VF/Vt and in 261/437 patients (60%) in PEA/asystole. Overall, 342/1145 patients (30%) reached a favorable outcome (cerebral performance categories level 1 or 2) at hospital discharge, respectively 274/708 (39%) in VF/Vt and 68/437 (16%) in PEA/asystole (P<0.001). After adjustment, in VF/Vt patients, TMH was associated with increased odds of good neurological outcome (adjusted odds ratio, 1.90; 95% confidence interval, 1.18 to 3.06) whereas in PEA/asystole patients, TMH was not significantly associated with good neurological outcome (adjusted odds ratio, 0.71; 95% confidence interval, 0.37 to 1.36).
  
  
  CONCLUSIONS
  In this large cohort of cardiac arrest patients, hypothermia was independently associated with an improved outcome at hospital discharge in patients presenting with VF/Vt. By contrast, TMH was not associated with good outcome in nonshockable patients. Further investigations are needed to clarify this lack of efficiency in PEA/asystole.
authors.affiliation: Service de Réanimation Médicale, Hôpital Cochin, Paris, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Dumas
authors.forename: David
authors.initials: D
authors.lastname: Grimaldi
authors.forename: Benjamin
authors.initials: B
authors.lastname: Zuber
authors.forename: Jérôme
authors.initials: J
authors.lastname: Fichet
authors.forename: Julien
authors.initials: J
authors.lastname: Charpentier
authors.forename: Frédéric
authors.initials: F
authors.lastname: Pène
authors.forename: Benoît
authors.initials: B
authors.lastname: Vivien
authors.forename: Olivier
authors.initials: O
authors.lastname: Varenne
authors.forename: Pierre
authors.initials: P
authors.lastname: Carli
authors.forename: Xavier
authors.initials: X
authors.lastname: Jouven
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Empana
authors.forename: Alain
authors.initials: A
authors.lastname: Cariou
mesh_terms: D000368:Aged; D015331:Cohort Studies; D004599:Electric Stimulation Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000503:physiopathology* / Q000628:therapy*; D011379:Prognosis; D011446:Prospective Studies; D012042:Registries; D012151:Resuscitation / Q000379:methods*; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000503:physiopathology / Q000628:therapy; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000503:physiopathology / Q000628:therapy