Abstract 144: Proinflammatory Cytokines and Catecholamine Release During Selective Head Cooling in a Porcine Model of Cardiac Arrest
Background. We have previously reported that selective head cooling initiated during CPR prevented increases in brain temperature and improved neurological outcome and post resuscitation myocardial dysfunction. We have now explored the relationship between head cooling during CPR and post resuscitation inflammation and catecholamine release. We hypothesized that head cooling during CPR would have beneficial effects on post resuscitation inflammation and catecholamine release.
Methods. Ventricular fibrillation was induced in 10 pigs (32 ± 2 kg) and was untreated for 10 min. CPR was then performed for 5 min prior to defibrillation. Coincident with the start of CPR, animals were randomly assigned to selective head cooling with the RhinoChill device, systemic cooling by a 4°C saline infusion (30 mL/kg in 30 min), or normothermic control. One hour after resuscitation animals were sacrified and blood, heart, brain and surrenal gland collected for further biochemical analyses. Rectal and jugular vein temperatures were monitored, together with invasive arterial and venous pressures. Cytokines were measured with the aid of Luminex and kit-5-Plex. Catecholamines were assessed by ELISA.
Results. All animals were resuscitated. Rectal and jugular vein temperatures significantly decreased in the hypothermic (head and systemic) animals compared to the control ones (p<0.01). Animals subjected to selective head cooling presented a significantly lower increase in plasmatic pro-inflammatory cytokines, compared to control animals (p<0.05, Table). Selective head cooling was also associated with lower post resuscitation plasma norepinephrine and heart and surrenal gland tissue norepinephrine, compared to control and systemic cooled animals (p<0.05, Table).
Conclusions. Selective head cooling blunted post resuscitation release of pro-inflammatory cytokines and norepinephrine. This effect might account for the outcome benefits previously reported.
- © 2012 by American Heart Association, Inc.