Efficacy of therapeutic hypothermia for neurological salvage in patients with cardiogenic sudden cardiac arrest: The importance of prehospital return of spontaneous circulation

Abstract

Aim of the Study: Cardiopulmonary resuscitation and mild therapeutic hypothermia (MTH) have improved neurological outcomes after sudden cardiac arrest, but the factors affecting favorable neurological outcome remain unclear. The aim of this study was to clarify these factors in patients in cardiac arrest treated with MTH. Methods: Forty-six consecutive patients (mean age, 59.4 ± 14.3 years; 37 men and 9 women) who had had cardiogenic cardiac arrest from January 2008 through December 2011, including cases that were and were not shockable, were enrolled in this study, and the factors affecting favorable neurological outcome were retrospectively investigated. The interval from cardiac arrest to cardiopulmonary resuscitation, the return of spontaneous circulation (ROSC), the start of MTH, and the attaining of the target temperature were retrieved from the medical records. The relationship between the neurological outcome and clinical findings, including the causes of cardiac arrest and vital signs before MTH, were also investigated. Results: Blood pressure and body temperature before MTH were higher, the interval from cardiac arrest to ROSC was shorter, and MTH was started earlier in patients with favorable neurological outcomes than in those with unfavorable outcomes. A multivariate logistic regression model revealed that the presence of prehospital ROSC was predictive of a favorable neurological outcome. In addition, renal failure during MTH occurred more frequently in patients with unfavorable neurological outcomes. Conclusion: MTH is associated with favorable neurological outcomes after sudden cardiac arrest, including those with non-shockable rhythms, especially in patients with prehospital ROSC.