Abstract 132: Evaluation of Therapeutic Hypothermia With Modified Less Invasive Cardiopulmonary Bypass Circuit for Out-of-Hospital Cardiac Arrest
Background: Mild therapeutic hypothermia has been integrated into management strategies for improving the neurological outcome of cardiac arrest with ventricular fibrillation. We introduce our rapid and safe hypothermia procedure with Modified Invasive Cardiopulmonary bypass Hypothermia (LICH) for Return of Spontaneous Circulation (ROSC) patients. This study aimed to evaluate the effects of these new procedures on the outcomes of cardiac arrest patients.
Methods: From January 2007 to April 2010, 40 patients were treated with mild hypothermia. These patients were divided into LICH procedure (Group L, N=17) and traditional cold blanket procedure (Group C, N=23) groups. The LICH procedure was indicated for unconscious ROSC patients under 75 years of age after cardiogenic cardiopulmonary arrest (CPA) with a witness, excluding those with brain hemorrhage, traumatic CPA, and risk of bleeding. Our modified LICH procedure quickly induced hypothermia via narrow pediatric cannulas on low-perfusion (1 l/min) artery-venous cardiopulmonary bypass (CPB) with minimal anticoagulation. Activated coagulation time (ACT) was set at 150 seconds for the modified LICH procedure. Any complications, time to target temperature, temperature stability, cytokines and neurological outcomes were compared. A favorable outcome was defined as a Cerebral Performance Category (CPC) of 1–2.
Results: There were no significant characteristic differences between groups L and C. As compared with Group C, Group L had higher rates of temperature stability (p<0.01), temperature over-shoot (93% vs. 0%, p<0.01), and quick induction (11 min vs. 307 min, p<0.01). However, the mortality rate (6% vs. 4%, NS), and that of a favorable neurological outcome (88% vs. 70%, NS) did not differ between the two groups. Three occult head traumas were seen in Group L, but a low ACT procedure helped to control major hemorrhagic complications.
Conclusions: These results indicate that our procedure has the advantages of not only rapid induction of therapeutic hypothermia for the target temperature, but safe maintenance in trauma cases. In addition, the low-perfusion pediatric bypass circuit system reduces afterload in CPB and the risks of embolism and limb malperfusion as compared with a full flow CPB.
- © 2010 by American Heart Association, Inc.