Abstract P45: Effects Of Carvedilol During Cardiopulmonary Resuscitation In A Rat Model Of Cardiac Arrest Induced By Airway Obstruction
The nonselective beta-adrenoceptor and selective alpha1-adrenoceptor blocker carvedilol is widely used in hypertensive and/or cardiac failure patients. However, there have been few studies regarding the effects of carvedilol on cardiac arrest induced by airway obstruction. The present study was performed to evaluate the effects of beta-blocker during cardiopulmonary resuscitation (CPR) in a rat model of cardiac arrest induced by airway obstruction. Twenty-four male Sprague Dawley rats were used. Animals were randomly assigned to one of two groups (n=12 per group), control group: no medication, treatment group: oral administration of beta-blocker (Carvedilol 10 mg/kg/day) for 5 days. After then, all animals were anesthetized with pentobarbital ip. Cardiac arrest was induced by airway obstruction. After 3 minutes of cardiac arrest, animals were received CPR. The rate of chest compressions (CC) was 240 –260/min in all groups. The rate of ventilation was 32 breaths/min in FIO2 0.21. After 5 minutes of CPR, epinephrine (0.02 mg/kg) was administered. There were no other therapies before, during or after cardiac arrest. The baseline HR and SAP in the treatment group were significantly lower than those in the control group (P<0.05). The time from airway obstruction to cardiac arrest was significantly longer in the treatment group than in the control group (P=0.029). There was significant negative correlation between the time from airway obstruction to cardiac arrest and baseline heart rates (R=0.547, P=0.0057). The rates of return of spontaneous circulation (ROSC) after cardiac arrest were 50% and 92% for the control and the treatment groups respectively. The rate of ROSC was significantly higher in treatment group (P=0.025). There were no significant differences about plasma cytokine levels. The present study indicates that oral administration of Carvedilol prolongs the time from airway obstruction to cardiac arrest and increases the rate of ROSC in a rat model of cardiac arrest induced by airway obstruction. These findings suggest that oral administration of Carvedilol may have beneficial effects on recovery of patients with cardiac arrest induced by airway obstruction.