title: A comparison between head cooling begun during cardiopulmonary resuscitation and surface cooling after resuscitation in a pig model of cardiac arrest.
abstract: OBJECTIVE
  Employing transnasal head-cooling in a pig model of prolonged ventricular fibrillation, we compared the effects of 4 hrs of head-cooling started during cardiopulmonary resuscitation with those of 8 hrs of surface-cooling started at 2 hrs after resuscitation on 96-hr survival and neurologic outcomes.
  
  
  METHODS
  Prospective controlled animal study.
  
  
  METHODS
  University-affiliated research laboratory.
  
  
  METHODS
  Domestic pigs.
  
  
  METHODS
  Twenty-four male pigs were subjected to 10 min of untreated ventricular fibrillation followed by 5 min of cardiopulmonary resuscitation. In the head-cooling group, hypothermia was started with cardiopulmonary resuscitation and continued for 4 hrs after resuscitation. In the surface-cooling group, systemic hypothermia with a cooling blanket was started, in accord with current clinical practices, at 2 hrs after resuscitation and continued for 8 hrs. Methods in the control animal studies were identical except for temperature interventions.
  
  
  RESULTS
  All animals were resuscitated except for one animal in each of the surface-cooling and control groups. After 5 min of cardiopulmonary resuscitation, jugular vein temperature was significantly decreased in the head-cooled animals. However, there were no differences in pulmonary artery temperatures among the three groups at that time. Nevertheless, both head-cooled and surface-cooled animals had an improved 96-hr survival after resuscitation. Significantly better neurologic outcomes were observed in early head-cooled animals in the first 3 days after resuscitation.
  
  
  CONCLUSIONS
  Early head-cooling during cardiopulmonary resuscitation continuing for 4 hrs after resuscitation produced favorable survival and neurologic outcomes in comparison with delayed surface-cooling of 8 hrs duration.
authors.affiliation: Well Institute of Critical Care Medicine, Rancho Mirage, CA, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Guan
authors.forename: Denise
authors.initials: D
authors.lastname: Barbut
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Yongqin
authors.initials: Y
authors.lastname: Li
authors.forename: Min-Shan
authors.initials: MS
authors.lastname: Tsai
authors.forename: Shijie
authors.initials: S
authors.lastname: Sun
authors.forename: Becky
authors.initials: B
authors.lastname: Inderbitzen
authors.forename: Max Harry
authors.initials: MH
authors.lastname: Weil
authors.forename: Wanchun
authors.initials: W
authors.lastname: Tang
mesh_terms: D000818:Animals; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D003326:Coronary Circulation; D006257:Head; D006323:Heart Arrest / Q000150:complications / Q000401:mortality / Q000628:therapy*; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D012121:Respiration, Artificial; D013552:Swine; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000209:etiology / Q000401:mortality / Q000628:therapy*