Therapeutic Hypothermia After the Return of Spontaneous Circulation

Induction of Therapeutic Hypothermia in the Pre-hospital Setting After the Return on Spontaneous Circulation: A Randomized Controlled Study

The purpose of this study is to determine if induced therapeutic hypothermia (ITH) in the pre-hospital setting of a four county emergency medical system (EMS) that serves both urban and rural communities improves meaningful survival from medical cardiac arrest.

Induction of therapeutic hypothermia after return of spontaneous circulation (ROSC) in medical cardiac arrest is increasingly becoming the standard of care in the hospital setting. Several studies, including two sentinel research papers in the New England Journal of Medicine, show improved neurologic outcome with induced therapeutic hypothermia (ITH). 4, 5 This research led to a class IIa recommendation by the American Heart Association for ITH after ROSC in V-Fib arrest and a class IIb recommendation after ROSC in all other classes of medial cardiac arrest.6 The role of ITH in the pre-hospital setting is less clear. Studies currently exist that both show a benefit and fail to support improved outcomes.7-9 It has been suggested that the short transport times in most urban EMS systems might be part of the reason that some studies have failed to find benefit of ITH in the pre-hospital setting. This is a prospective, randomized controlled trial involving all patients transported by CCEMS who have ROSC after a medical cardiac arrest and who are transported to a hospital that can continue ITH for 24 hours. All comatose patients who meet inclusion criteria will be randomized to either ITH in addition to continued treatment under standing protocols or regular care without ITH. Assignment to the two treatment arms will be done using the EMS number which is generated when the ambulance is dispatched to a call. Even numbered patients will have continued standard therapy while odd numbered patients will receive ITH.

Induced hypothermia after the return of spontaneous circulation by the application of ice packs to the axilla and groin with cold IV fluids

Treatment of the return of spontaneous circulation under standing paramedic protocol without the addition of induced therapeutic hypothermia

Induced hypothermia and continued treatment under standing paramedic protocols. To determine if ITH in the pre-hospital setting improves outcomes at hospital discharge

Patients will be treated under standing paramedic protocols without the induction of hypothermia. To determine if there is a difference in these outcomes in patients with prolonged transport to the hospital (> 20 minutes) versus those with shorter transport times.

Inclusion Criteria: All patient transported by CCEMS with ROSC after a medical Cardiac Arrest to hospitals that can continue ITH Exclusion Criteria: Less than 18 Cardiac arrest due to trauma or hemorrhage Pregnant women patients whom are already hypothermic transported to a hospital that can not maintain hypothermia for 24 hours

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