title: Therapeutic hypothermia after cardiac arrest: a retrospective comparison of surface and endovascular cooling techniques.
abstract: OBJECTIVE
  Therapeutic hypothermia (32-34 degrees C) is recommended for comatose survivors of cardiac arrest; however, the optimal technique for cooling is unknown. We aimed to compare therapeutic hypothermia using either surface or endovascular techniques in terms of efficacy, complications and outcome.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Thirty-bed teaching hospital intensive care unit (ICU).
  
  
  METHODS
  All patients (n=83) undergoing therapeutic hypothermia following cardiac arrest over a 2.5-year period. The mean age was 61+/-16 years; 88% of arrests occurred out of hospital, and 64% were ventricular fibrillation/tachycardia.
  
  
  METHODS
  Therapeutic hypothermia was initiated in the ICU using iced Hartmann's solution, followed by either surface (n=41) or endovascular (n=42) cooling; choice of technique was based upon endovascular device availability. The target temperature was 32-34 degrees C for 12-24 h, followed by rewarming at a rate of 0.25 degrees Ch(-1).
  
  
  RESULTS
  Endovascular cooling provided a longer time within the target temperature range (p=0.02), less temperature fluctuation (p=0.003), better control during rewarming (0.04), and a lower 48-h temperature load (p=0.008). Endovascular cooling also produced less cooling-associated complications in terms of both overcooling (p=0.05) and failure to reach the target temperature (p=0.04). After adjustment for known confounders, there were no differences in outcome between the groups in terms of ICU or hospital mortality, ventilator free days and neurological outcome.
  
  
  CONCLUSIONS
  Endovascular cooling provides better temperature management than surface cooling, as well as a more favorable complication profile. The equivalence in outcome suggested by this small study requires confirmation in a randomized trial.
authors.affiliation: Department of Intensive Care, Guy's and St. Thomas' NHS Foundation Trust, Westminster Bridge Road, London SE1 7EH, United Kingdom. michael.gillies@nhs.net
authors.forename: Michael A
authors.initials: MA
authors.lastname: Gillies
authors.forename: Rosalie
authors.initials: R
authors.lastname: Pratt
authors.forename: Craig
authors.initials: C
authors.lastname: Whiteley
authors.forename: Jamie
authors.initials: J
authors.lastname: Borg
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Beale
authors.forename: Shane M
authors.initials: SM
authors.lastname: Tibby
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003422:Critical Care / Q000379:methods; D005260:Female; D006323:Heart Arrest / Q000209:etiology / Q000401:mortality / Q000628:therapy*; D006396:Hematemesis / Q000209:etiology; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000628:therapy; D011674:Pulse; D012189:Retrospective Studies; D012770:Shock, Cardiogenic / Q000209:etiology; D017180:Tachycardia, Ventricular / Q000150:complications; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000150:complications