Abstract 97: Intra-arrest Induction of Therapeutic Hypothermia via Large-Volume, Ice-Cold Saline Infusion Results in Improved Outcomes Among Out-of-Hospital Cardiac Arrests of Cardiac Etiology

Abstract

Background: New York City Project Hypothermia is a collaborative effort involving the Fire Department of New York (FDNY), Greater New York Hospital Association, Health and Hospitals Corporation, the Regional Emergency Medical Advisory Committee, and the New York State Department of Health. As part of this effort, the FDNY implemented a new pilot protocol in the New York City 9-1-1 System that introduced the induction of therapeutic hypothermia during initial resuscitation efforts via large-volume ice-cold saline infusion. Purpose: We sought to assess the effects of this protocol on immediate survival end-points following out-of-hospital cardiac arrest (OOHCA) of cardiac etiology. Methods: OOHCA data was analyzed for the following periods: August 1, 2009 - May 31, 2010 (historicalcontrol group) and August 1, 2010 - May 31, 2011 (study group). Except for the intra-arrest induction of hypothermia, no other aspect of the regional resuscitation protocols differed between the two periods. Standard Utstein definitions were utilized. Fisher's exact test was utilized, and a p <0.05 was considered significant. Results: 4,459 / 5,582 (79.9%) of resuscitations during the control period and 3,581 / 4,727 (75.8%) of resuscitations during the study period were of cardiac etiology. The groups did not differ with respect to age, gender, race, response time, bystander witnessed status, or frequency of bystander CPR. Patients in the study period were less likely to have an EMS-witnessed arrest (6.5% vs 7.8%, p=0.03). Return of spontaneous circulation (ROSC) and sustained ROSC were improved in the study group as compared to the control group: 31.1% vs 26.8% (p<0.0001) and 23.6% vs 19.9% (p<0.0001), respectively. Conclusion: The initiation of therapeutic hypothermia via large volume, ice-cold saline infusion improves immediate survival for non-traumatic out-of-hospital cardiac arrest of cardiac etiology. Further study is required to identify specific populations for whom this therapy is most appropriate.