title: Predictors of external cooling failure after cardiac arrest.
abstract: OBJECTIVE
  External cooling is largely employed to induce hypothermia in comatose survivors of cardiac arrest (CA), but can fail to reach the target temperature in a reasonable time. We aimed to assess the rate of failure of external cooling after CA and to determine failure predictors.
  
  
  METHODS
  The study was a retrospective review of a prospectively acquired database in the setting of a 24-bed ICU in a university hospital. All consecutive patients admitted for CA from May 2002 to April 2010 and treated by external cooling were considered. Patients who were already hypothermic on admission, patients dying within 24 h, patients cooled by an internal technique and patients in whom hypothermia had not been attempted were not studied. External cooling failure was defined as the inability to reach a temperature below 34 °C during the first 12 h after CA onset.
  
  
  RESULTS
  Among 1,036 patients admitted to the ICU, 594 were included in the analysis and in 191 (32 %) the target temperature could not be achieved within the 12 h following CA. Independent risk factors for external cooling failure were an early coronary angiography intervention (OR 3.75, p < 0.001), a high body weight (OR 1.02 per kilogram, p = 0.007), a high temperature on ICU admission (OR 1.47 per degree, p = 0.001) and a long delay between collapse and the start of cooling (OR 1.15, p = 0.05). Conversely, early haemodialysis (OR 0.27, p < 0.001) and male gender (OR 0.47, p = 0.02) were significantly associated with cooling success.
  
  
  CONCLUSIONS
  External cooling failure occurred in nearly one-third of patients with CA and was associated with easily identified risk factors. This emphasizes the interest in early cooling and alternative techniques in these patients.
authors.affiliation: Medical Intensive Care Unit, Cochin Hospital, Groupe Hospitalier Cochin Broca Hôtel-Dieu, Assistance Publique des Hôpitaux de Paris, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France. sylvie.ricome@cch.aphp.fr
authors.forename: Sylvie
authors.initials: S
authors.lastname: Ricome
authors.forename: Florence
authors.initials: F
authors.lastname: Dumas
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mongardon
authors.forename: Olivier
authors.initials: O
authors.lastname: Varenne
authors.forename: Jérôme
authors.initials: J
authors.lastname: Fichet
authors.forename: Frédéric
authors.initials: F
authors.lastname: Pène
authors.forename: Benjamin
authors.initials: B
authors.lastname: Zuber
authors.forename: Benoît
authors.initials: B
authors.lastname: Vivien
authors.forename: Julien
authors.initials: J
authors.lastname: Charpentier
authors.forename: Jean-Daniel
authors.initials: JD
authors.lastname: Chiche
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Mira
authors.forename: Alain
authors.initials: A
authors.lastname: Cariou
mesh_terms: D000368:Aged; D001831:Body Temperature / Q000502:physiology; D003128:Coma / Q000209:etiology / Q000628:therapy; D005260:Female; D006323:Heart Arrest / Q000150:complications / Q000628:therapy*; D006785:Hospitals, University; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012151:Resuscitation / Q000379:methods / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D017211:Treatment Failure