The Efficacy of Surface and Endovascular Cooling Methods During Therapeutic Hypothermia after Cardiac Arrest

ABSTRACT

PURPOSE: According to the 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care, unconscious adult patients with ROSC after out-of-hospital cardiac arrest should be cooled to between 32degrees C and 34degrees C for 12 to 24 hours. Two recent randomized controlled trials that included comatose survivors of cardiac arrest have documented that therapeutic hypothermia improved the neurological recovery. (ED note Newer cooling devices have recently been introduced, such as endovascular...?)We have introduced newer devices, such as endovascular cooling devices, so we compared endovascular cooling with the previously used surface cooling Methods. METHODS: This is a cohort study of patients with ROSC (>24hours) after cardiac arrest and who were admitted to the intensive care unit in a tertiary hospital over a twentyeight month period from September 2006 to December 2008 and they had received therapeutic hypothermia. The patients'baseline characteristics, the mortality, the neurologic outcomes, the side effects during therapeutic hypothermia and other factors were evaluated according to the cooling methods. RESULTS: Seventy-five patients were included over a 28 month period. Surface cooling methods were used in 37 patients, and endovascular cooling methods were used in 38 patients. There were no significant differences of the mortality and the neurologic outcome according to the cooling methods (p=0.973, 0.937). The time from collapse to reaching therapeutic hypothermia was 587.14+/-384.18 minutes for surface cooling and 496.24+/-213.83 minutes for endovascular cooling (p=0.105). The rewarming time was 451.09+/-229.93 minutes and 802.38+/-209.09 minutes for each cooling method, respectively, and the difference was statistically significant (p=0.002). There were no significant differences of the side effects during therapeutic hypothermia between the surface and endovascular cooling methods. CONCLUSION: Endovascular cooling methods are useful to maintain the target temperature within a narrower range and these methods have the advantage of automatic feedback control of the temperature and controlled rewarming. There were no significant differences in mortality, the neurologic outcome and other side effects between the surface and endovascular cooling methods during therapeutic hypothermia after cardiac arrest.