Abstract 17617: Post-cardiac Arrest Mortality Rates With Different Levels of Targeted Temperature Management within Patient Illness Severity Categories
Introduction: There are 380,000 out-of-hospital cardiac arrests (OHCA) in the United States each year. Controlling temperature improves outcome. It is unknown if different illness severity may require different goal temperatures.
Hypothesis: When controlling for Pittsburgh Cardiac Arrest Category (PCAC), there is no difference in mortality between treatment at 33°C or 36°C.
Methods: Review of existing QI database between 12/2013 and 12/2014. We abstracted location of arrest, primary rhythm, initial illness severity (PCAC), survival, presence of fever and neurologic outcome. We defined four categories of PCAC: I) awake, II) coma + mild cardiopulmonary dysfunction, III) coma + moderate-severe cardiopulmonary dysfunction, and IV) coma without brainstem reflexes. Good neurologic outcome was defined as a CPC of 1-2 or mRS of 0-2. Chi-squared analysis compared the cohorts. Logistic regression was used to determine factors associated with survival and good neurologic outcome. Candidate variables included age, primary rhythm of arrest, PCAC, development of fever in the first 48 hours and goal temperature.
Results: Of 165 patients studied, 102 (62%) were male, with a mean age of 58 (SD = 18). The most common primary rhythm was VF/VT (53; 32%). Goal temperature of 36°C was used in 92 (56%), temperature of 33°C was used in 60 (36%), and no temperature management was used in 13 (36%). Fever was more common in patients treated with goal temperature of 36°C (28% vs. 7%; p=0.004).
Survival did not differ between temperature management strategies (PCAC II 33°C: 2 (50%), PCAC II 36°C 24 (80%); PCAC III 33°C: 3 (75%), PCAC III 36°C: 6 (43%); PCAC IV 33°C: 4 (8%), PCAC IV 36°C: 7 (18%). In the multivariate analysis, only PCAC was associated with survival (OR 0.35; 95% CI 0.23, 0.55), good CPC (OR 0.30; 95% CI 0.15, 0.61) and good mRS (OR 0.33; 95% CI 0.16, 0.67).
Conclusions: After accounting for PCAC, survival and good neurologic do not differ between temperature management strategies of 33°C or 36°C. Fever is more common in patients treated at goal temperature of 36°C. We noted a systematic trend towards application of 33°C to higher illness severity patients. This bias needs to be robustly controlled for in future observational work to prevent confounding by indication.
Author Disclosures: J.C. Rittenberger: Research Grant; Modest; Laerdal Foundation for Acute Care Medicine. Honoraria; Modest; Bard Medical (sponsor of Korean TTM Course); EMCREG International Symposium 2015; Heart Rescue; University of Pennsylvania. Employment; Significant; University of Pittsburgh; UPMC. Research Grant; Significant; American Heart Association Grant-in-Aid; NINDS. P. Coppler: None. F.X. Guyette: None. C.W. Callaway: Ownership Interest; Modest; Patent licensed to Medtronic for defibrillation analysis. J. Elmer: None. A.A. Doshi: None. D. Slowey: None.
- © 2015 by American Heart Association, Inc.