Therapeutic Hypothermia to Improve Outcomes Post OHCA By: L. Bloxham, E. Foley, D. Price, & L. Pendergraft College of Nursing, University of Oklahoma - 2010
PICO Question P opulation Adult survivors of cardiac arrest who have regained circulation but remain comatose I ntervention Therapeutic Hypothermia (32 to 34 C) C omparison Maintaining Normothermia (37 C) O utcome Reducing mortality and improving neurological outcomes
PICO Question In adult survivors of primary cardiac arrest who have regained circulation but remain comatose, what is the effect of therapeutic hypothermia (32 to 34 C) on reducing mortality and improving neurological outcomes compared with maintaining normothermia (37 C) post-cardiac arrest?
Definitions Adult 18-64 years old Normothermia 37 C Long Term Minimum of 1 year Cardiac Arrest Cardiac arrest is defined as cessation of cardiac mechanical activity and is confirmed by the absence of signs of circulation. American Heart Association (2009)
Definitions Comatose A score ranging from 3-8 using the Glasgow Coma Scale ROSC Return of spontaneous circulation Therapeutic Hypothermia Patients cooled to a core temperature between 32 to 34 C for 12-24 hours Good Neurological Outcome Cerebral Performance Category (CPC) scores of one or two American Heart association (2009)
Arrich, J., Holzer, M., Herkner, H., Müllner, M. (2009)
Systematic review & meta-analysis. Four trials and one abstract reporting on a total of 481 patients were included in the review.
Therapeutic Hypothermia (TH) improves survival and neurologic outcome in patients successfully resuscitated from cardiac arrest when they meet the following criteria: out-of-hospital cardiac arrest of cardiac cause with VF/VT as first recorded rhythm.
Hypothermia After Cardiac Arrest Study Group. (2002)
Randomized control trial. A total of 275 patients enrolled in study. Included in the study were patients 18-75 years old that had a witnessed cardiac arrest, presumably or cardiac origin, with ventricular fibrillation or non-perfusing ventricular tachycardia as the initial rhythm.
Systematic cooling to 32°C-34°C for 24 hours increased the chance of survival and of a favorable neurological outcome (Cerebral performance scale category 1 or 2).
Retrospective study. A total of 109 patients resuscitated from out of hospital cardiac arrest with initial rhythms of VF, asystole, or pulseless electrical activity (PEA). All were in a persistent coma at admission.
In patients with VF as the initial rhythm, 55.8% of patients treated with TH had a good outcome compared to 25.6% of patients treated with standard resuscitation (SR).
60.5% of TH patients survived to discharge compared to 44.2% of SR patients.
Is broadening the inclusion criteria for patients to receive therapeutic hypothermia beneficial?
Is there a decreased length of stay as a result of therapeutic hypothermia?
Would initiating hypothermia in the ambulance on the way to the hospital further increase survival?
Advanced life support. In: 2005 International Consensus Conference on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Circulation 2005 Nov 29;112(22 Suppl):III25-54. Ambrose, R. (2004). The Cost of cardiac arrest in the workplace. Occupational Health & Safety, Retrieved from http://ohsonline.com/Articles/2004/09/The-Cost-of-Cardiac-Arrest-in-the- Workplace.aspx?Page=2 American Heart Association. (2009). News releases: Cooling therapy for cardiac arrest survivors is as cost-effective as accepted treatments for other conditions. Retrieved from http://americanheart.mediaroom.com/index.php?s=43&item=795 . Arrich, J., Holzer, M., Herkner, H., Müllner, M. (2009). Hypothermia for Neuroprotection in adults after cardiopulmonary resuscitation. Cochrane Database of Systematic Reviews , 4, 1-33. References
Barht, G. (2009). Cooler heart, better odds: induced hypothermia. Nursing Management, 40(7), Retrieved from http://www.nursingcenter.com/prodev/ce_article.asp?tid=869342 Centers for Disease Control. (2009). Chronic disease prevention and health promotion: Heart disease and stroke prevention. Retrieved from http://www.cdc.gov/chronicdisease/resources/publications/AAG/dhdsp.htm Heart Rhythm Foundation, (n. d.). Sudden cardiac arrest statistics. Heart Rhythm Facts and Stats. Retrieved from http://www.heartrhythmfoundation.org/facts/scd.asp Merchant, R.M., Becker, L.B., Abella, B.S., Asch, D.A., Groeneveld, P.W. (2009). Cost-effectiveness of therapeutic hypothermia after cardiac arrest. Circulation: Cardiovascular Quality & Outcomes, 2(5), 421-28. National Heart, Lung and Blood Institute. (2008). National Institute of Health news: Automated external defibrillators and CPR are equally helpful for sudden cardiac arrest in the home. Retrieved from http://public.nhlbi.nih.gov/newsroom/home/GetPressRelease.aspx?id=256 . References