Abstract 17383: Exploratory Study of Emergency Cardiopulmonary Bypass for Resuscitation and Long-term Survival From Prolonged Ventricular Fibrillation Cardiac Arrest in Rats
BACKGROUND: Emergency cardiopulmonary bypass (ECPB) may achieve successful resuscitation after prolonged cardiac arrest (CA) when conventional cardiopulmonary resuscitation (CPR) fails. A rodent model of ventricular fibrillation (VF) CA would allow optimizing ECPB use. In this study, we assessed the feasibility of a 10 min ventricular fibrillation (VF) CA model with ECPB resuscitation in rats in terms of return of spontaneous circulation (ROSC) rate and long-term survival with neurologic and histologic outcome.
METHODS: The ECPB setup consisted of an open reservoir, a roller pump, a capillary membrane oxygenator, primed with 15 mL of heparinized crystalloid solution, connected by silicone tubing to a draining catheter in the right jugular vein and an inflow catheter in the right femoral artery, and a circulating water bath. VF was initiated in adult male Sprague-Dawley rats (450 g, anesthetized) endocardially. After 10 min of CA, rats were resuscitated with ECPB at a flow rate of 50 mL/min, mechanical ventilations and drugs (epinephrine, bicarbonate, heparin). With start of ECPB, rats were cooled to mild therapeutic hypothermia. After defibrillation and ROSC, rats were weaned from CPB and maintained at 33°C for 5 hours. Outcome parameters included resuscitability, survival to 1 month with neurologic deficit score (NDS; 0% = normal, 100% = dead), overall performance category (OPC; 1 = normal, 5 = dead) and a histologic damage score (HDS, pending). All data is presented as mean±SD.
RESULTS: ROSC was achieved in 14 / 14 animals within 3.3±0.9 min on bypass, 10 / 14 animals survived to 1 month (7 OPC 1, 3 OPC 2). NDS was 1.9±2.5. All animals experienced marked neurologic (motoric, sensory and cognitive) and overall improvement over the long observation period. The deficits that persisted were motoric on the lower extremities.
CONCLUSION: In a rat model of prolonged VF CA, ECPB resuscitation with mild hypothermia leads to 100% resuscitability and favorable functional outcome and long-term survival after 10 min of VF.
- © 2013 by American Heart Association, Inc.