Abstract 91: Pharmacologically Induced Hypothermia Minimizing Shivering Following Cardiopulmonary Resuscitation
Background: Therapeutic hypothermia reduces oxygen consumption and ischemic injury following successful resuscitation; thereby improves outcomes. However, all the currently available physical cooling techniques cause severe shivering which increases systemic oxygen consumption, and makes it more difficult to maintain target temperature. In this study, we examined the effects of pharmacologically induced hypothermia with WIN 55, 212-2 on shivering during hypothermia in a porcine model of CPR.
Hypothesis: We hypothesized that when WIN55, 212-2 is administered following resuscitation together with surface cooling, it will rapidly reduce the body temperature (BT) without shivering; therefore it is easier to maintain the target temperature.
Methods: Ventricular fibrillation was electrically induced and untreated for 7 mins in 21 male swine weighing 35±2kg. Defibrillation was attempted after 5 mins of CPR. The resuscitated animals were randomized to receive the treatment of either WIN 55, 212-2, surface cooling or the combination of WIN55, 212-2 + surface cooling at 5 mins post-resuscitation. The pharmacological cooling was induced by intravenous infused WIN 55, 212-2 (1.0mg/kg/h). The cooling blanket was utilized for surface cooling. The blood temperature, a total dosage of pentobarbital utilization and the incident and duration of shivering during hypothermia were continuously monitored.
Results: During hypothermia, the incident and duration of shivering and the total usage of pentobarbital were significantly reduced in WIN55,212-2 and combination groups when compared with surface cooling group (p<0.001). That was associated with more rapidly decreased blood temperature and easily maintained with 32-34°C in the combination group.
Conclusions: The shivering during hypothermia is minimized by pharmacologically induced hypothermia with WIN 55, 212-2 alone or together with surface cooling. It may provide a new option for inducing hypothermia.
- © 2012 by American Heart Association, Inc.