Code Freeze

Abstract

BACKGROUND:

According to statistics from the American Heart Association, there are over 325,000 deaths from cardiac arrest per year. The current survival rate from cardiac arrest is improved at 6-12 % overall with the use of therapeutic hypothermia. Studies indicate that this intervention increases chances of survival from both in and out of hospital cardiac arrest. However, it is currently underutilized and there is large variation in survival rate across the globe. Our research evaluated the results of multiple studies regarding the survival rates at discharge using the intervention of therapeutic hypothermia.

SEARCH METHODS:

We searched the following databases: the Cochrane Library, MEDLINE, CINAHL, OVID, and PubMED. The following key words were used to search the databases: “hypothermia”, “cooling methods”, “survival of cardiac arrest”, “therapeutic hypothermia”, “code freeze”, “hypothermia protocol”, “cardiac arrest and hypothermia”

SELECTION CRITERIA:

Studies included in the research were meta-analysis, randomized control trials, systematic reviews, quasi-experimental, cohort studies and surveys. Inclusion criteria focused on: adult patients with out of hospital cardiac arrests, no significant trauma, and heart rhythms that were shockable and none shockable. All subjects were treated with in the six hour window with conventional cooling methods to reach 32-34 degrees Celsius.

MAIN RESULTS:

We reviewed nine different articles with over 5000 patients in the combined studies. Data collected focused only on the survival at discharge from the hospital. All qualitative studies showed significant reduction of mortality in the intervention groups. A variety of conventional cooling methods were utilized to achieve goal temperature of 32-34 degrees Celsius over a period of 12-24 hours. Conventional cooling methods consisted of: cold intravenous fluids, ice packs, cooling blankest, mattresses, mists, fans and helmets. While some systematic reviews did not provide specific numerical values for survival rate, those studies that did indicated an average improved survival rate of 52% over the control group.

CONCLUSION:

Therapeutic hypothermia has been shown to significantly improve survival in out of hospital cardiac arrests. Though studies reveal this intervention is clearly beneficial the implementation is limited and varies among hospitals. More education and awareness of the benefits of therapeutic hypothermia needs to be dispersed among health care professionals. More research and randomized control studies should be conducted to further solidify the advantages.