Survival and neurological outcomes after nasopharyngeal cooling or peripheral vein cold saline infusion initiated during cardiopulmonary resuscitation in a porcine model of prolonged cardiac arrest.
OBJECTIVE
We have previously demonstrated that nasopharyngeal cooling initiated during cardiopulmonary resuscitation improves the success of resuscitation. In this study, we compared the effects of nasopharyngeal cooling with cold saline infusion initiated during cardiopulmonary resuscitation on resuscitation outcome in a porcine model of prolonged cardiac arrest. We hypothesized that nasopharyngeal cooling initiated during cardiopulmonary resuscitation would yield better resuscitation outcome when compared with cold saline infusion.


METHODS
Randomized, prospective animal study.


METHODS
University-affiliated research laboratory.


METHODS
Yorkshire-X domestic pigs (Sus scrofa).


METHODS
Ventricular fibrillation was induced in 14 pigs weighing 38 +/- 2 kg. After 15 mins of untreated ventricular fibrillation, cardiopulmonary resuscitation was performed for 5 mins before defibrillation. Coincident with the start of cardiopulmonary resuscitation, animals were randomly assigned to receive nasopharyngeal cooling with the aid of the RhinoChill Device (BeneChill, San Diego, CA) or cold saline infusion with 30 mL/kg 4 degrees C saline. One hour after restoration of spontaneous circulation, surface cooling was begun with the aid of a water blanket in both groups and maintained for 4 hrs.


RESULTS
Jugular vein temperature significantly decreased in animals subjected to nasopharyngeal cooling in comparison with those receiving cold saline infusion (p < .01). Core temperature, however, decreased only in animals receiving cold saline infusion (p < .01). Coronary perfusion pressure was significantly higher in the animals treated with nasopharyngeal cooling (p = .02). All seven animals treated with nasopharyngeal cooling were successfully resuscitated in contrast to only two animals resuscitated in the cold saline infusion group (p = .02).


CONCLUSIONS
In this model, nasopharyngeal cooling initiated during cardiopulmonary resuscitation improved the success of resuscitation compared to cooling with cold saline infusion.
Yu
Tao
T
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, USA.
Barbut
Denise
D
Ristagno
Giuseppe
G
Cho
Jun Hwi
JH
Sun
Shijie
S
Li
Yongqin
Y
Weil
Max Harry
MH
Tang
Wanchun
W
D000818:Animals; D001833:Body Temperature Regulation / Q000502:physiology; D002545:Brain Ischemia / Q000503:physiopathology; D016887:Cardiopulmonary Resuscitation / Q000379:methods*; D004195:Disease Models, Animal; D004562:Electrocardiography; D006323:Heart Arrest / Q000401:mortality / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology; D017052:Hospital Mortality; D007036:Hypothermia, Induced / Q000379:methods*; D007262:Infusions, Intravenous; D008297:Male; D009305:Nasopharynx / Q000503:physiopathology; D012815:Signal Processing, Computer-Assisted; D012965:Sodium Chloride / Q000008:administration & dosage; D013552:Swine; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000401:mortality / Q000503:physiopathology
D012965:Sodium Chloride