Does therapeutic hypothermia during extracorporeal cardiopulmonary resuscitation preserve cardiac function?

• Published in: Journal of translational medicine 2016-12, Vol.14 (1), p.345-345, Article 345
• Main Authors: Bergan, Harald A, Halvorsen, Per S, Skulstad, Helge, Fosse, Erik, Bugge, Jan F
• Format: Article
• Language: English
• Subjects: Animals; Aspartate Aminotransferases - blood; Blood Gas Analysis; Blood Pressure - drug effects; Blood Pressure - physiology; Body Temperature - drug effects; Cardiopulmonary Resuscitation; Cardiotonic Agents - pharmacology; Dosage and administration; Electric Countershock; Health aspects; Heart - drug effects; Heart - physiopathology; Heart Rate - drug effects; Heart Rate - physiology; Hemodynamics - drug effects; Hypothermia; Hypothermia, Induced; Magnetic Resonance Imaging; Staining and Labeling; Sus scrofa; Troponin; Troponin T - blood; Ventricular Fibrillation - blood; Ventricular Fibrillation - physiopathology; Ventricular Fibrillation - therapy
• ISSN: 1479-5876; 1479-5876
• DOI: 10.1186/s12967-016-1099-y

Extracorporeal cardiopulmonary resuscitation (E-CPR) is increasingly used as a rescue method in the management of cardiac arrest and provides the opportunity to rapidly induce therapeutic hypothermia. The survival after a cardiac arrest is related to post-arrest cardiac function, and the application of therapeutic hypothermia post-arrest is hypothesized to improve cardiac outcome. The present animal study compares normothermic and hypothermic E-CPR considering resuscitation success, post-arrest left ventricular function and magnitude of myocardial injury. After a 15-min untreated ventricular fibrillation, the pigs (n = 20) were randomized to either normothermic (38 °C) or hypothermic (32-33 °C) E-CPR. Defibrillation terminated ventricular fibrillation after 5 min of E-CPR, and extracorporeal support continued for 2 h, followed by warming, weaning and a stabilization period. Magnetic resonance imaging and left ventricle pressure measurements were used to assess left ventricular function pre-arrest and 5 h post-arrest. Myocardial injury was estimated by serum concentrations of cardiac TroponinT and Aspartate transaminase (ASAT). E-CPR resuscitated all animals and the hypothermic strategy induced therapeutic hypothermia within minutes without impairment of the resuscitation success rate. All animals suffered a severe global systolic left ventricular dysfunction post-arrest with 50-70% reductions in stroke volume, ejection fraction, wall thickening, strain and mitral annular plane systolic excursion. Serum concentrations of cardiac TroponinT and ASAT increased considerably post-arrest. No significant differences were found between the two groups. Two-hour therapeutic hypothermia during E-CPR offers an equal resuscitation success rate, but does not preserve the post-arrest cardiac function nor reduce the magnitude of myocardial injury, compared to normothermic E-CPR. Trial registration FOTS 4611/13 registered 25 October 2012.