Abstract 2412: Rapid Induction Of Head Cooling By The Intranasal Route During Cardiopulmonary Resuscitation Improves Survival and Neurological Outcomes
Introduction: Current guidelines recommend mild hypothermia for all unconscious patients of cardiac arrest after return of spontaneous circulation (ROSC). However, the effects of intra-resuscitation cooling, specifically targeted at the brain, are still unclear.
Hypothesis: Early head cooling during cardiopulmonary resuscitation (CPR) culminating in systemic hypothermia improves 96 hour survival and neurological outcome in a pig model of prolonged cardiac arrest.
Methods: Ventricular fibrillation was electrically induced in 16 domestic pigs and untreated for 10 minutes. After 5 minutes of CPR, defibrillations and additional CPR were attempted until ROSC, or for a maximum of 15 minutes. In hypothermia group, cooling was induced coincident with start of CPR using a transnasal spray of a highly volatile perfluorochemical and continued until core temperature (Tc) measured in the pulmonary artery was reduced to 34°C. The spray was then adjusted to maintain Tc below 34.5°C for 4 hours after ROSC. Retrograde right jugular vein temperature (Tjv), which has been previously reported as a indicator of brain temperature, and Tc were continuously recorded. Survival and Neurological Deficit Score (NDS) were recorded daily for 96 hours after ROSC.
Results: Baseline Tc was maintained at 38.0°C in both groups. All animals except one in the control group were successfully resuscitated. After 5 minutes of CPR, Tjv was significantly lower in the hypothermia group (34.2±4.5°C vs 38.1±0.3°C, p<0.05). The hypothermia group showed significantly improved 96 hour survival (8/8 vs 2/8, p=0.007) and improved neurological outcomes (Table 1⇓).
Conclusion: Rapid induction of head cooling by the intranasal route during CPR culminating in systemic hypothermia, significantly improved 96 hour survival and neurological outcomes. Table 1⇓ Neurological Deficit Score after resuscitation expressed in median (min, max)