1. CODE FREEZE Svetlana Taylor, Eden Thompson, Jenny Vandiver
BACKGROUND
CLINICAL QUESTION
INCLUSION & EXCLUSION CRITERIA
APPRAISAL OF THE EVIDENCE
Conventional Cooling Methods
CLINICAL IMPLICATIONS
FURTHER RESEARCH
INCLUSION:
Non traumatic cardiac arrest with ROSC
Core temperature 34-C at presentation
Time to initiation of hypothermia is 6 hours
Comatose after ROSC: GCS 8, and no purposeful movement to pain
Age limit: 18 and up
EXCLUSION:
Uncontrolled gastrointestinal bleeding
Cardiovascular instability as evidenced by uncontrollable arrhythmias, refractory hypotension (unable to achieve target mean arterial pressure 65 mm Hg despite interventions)
Sepsis as suspected cause of cardiac arrest
Suspected intracranial hemorrhage
Major intracranial, intra-thoracic, or intra-abdominal surgery within 14 days
Gravid pregnancy
*Abbreviations: GCS, Glasgow Coma Scale; ROSC,
return of spontaneous circulation
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. Hypothermia protocol has been studied in cardiac arrest patients since the early 2000’s. As the data evolved it was evident that this intervention has improved mortality rate in this patient population. 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.
Code Freeze primarily utilizes the following conventional cooling methods:
The core temperature goal of degrees Celsius
Induction with in 6 hours of cardiac arrest
Maintained temperature for hours after inducing hypothermia
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.
The nurse’s role: nursing staff must stay familiar with and have check off skills of “Code Freeze” in order to stay current with the protocol. Critical thinking skills are essential to identifying cardiac arrest patients who are potential candidates in order to ensure that all those who are eligible do receive the intervention.
More education and awareness of the benefits of therapeutic hypothermia needs to be dispersed among health care professionals. Further research and randomized control trials should be conducted to further solidify the benefits of therapeutic hypothermia.
In adult cardiac arrest patients, does initiation of hypothermia protocol vs. no hypothermia protocol improve the incidence of patient survival to discharge from the hospital?
SURVIVAL RATE AT DISCHARGE
SEARCH FOR EVIDENCE
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 within the six hour window with conventional cooling methods to reach degrees Celsius
*Data averaged from nine articles containing survival rate statistics
Current findings suggest a need for additional randomized controlled trials to further evaluate the benefits of hypothermia in cardiac arrest patients. Despite findings, there is still a lack of implementation possibly due to scarcity of resources. Further research should quantify the resources required for widespread hypothermia induction. While benefits are clearly evident in the current literature, more data should be analyzed within this population and disseminated in widely circulated publications in order to gain support for application and encourage more consistent use of hypothermia protocol.
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 quantitative studies showed significant reduction of mortality in the intervention groups. A variety of conventional cooling methods were utilized to achieve goal temperature of degrees Celsius over a period of 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 within the intervention group of 52% over the control group.