Effects of thoracic epidural anesthesia on myocardial changes induced by brain death

• Grant number: 08/11441-0
• Support type: Regular Research Grants
• Duration: June 01, 2009 - May 31, 2011
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal researcher: Luiz Felipe Pinho Moreira
• Grantee: Luiz Felipe Pinho Moreira
• Home Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Heart transplant is in the best alternative treatment for patients refractory heart failure. Unfortunately, beyond the small number of donors, about 30% of donated hearts are not enough to be transplanted because of a serious disorder that affects those organs after brain death. Cardiac dysfunction after brain death is associated with a hyperdynamic condition resulting from uncontrolled autonomic response, which can be avoided by the use of beta-adrenergic blockers. Thoracic epidural anesthesia provides an effective autonomic blockade, with a reduction in hemodynamic instability in the states of shock. Therefore, the purpose of this study is to analyze the effects of continuous thoracic epidural anesthesia in rats subjected to brain death, regarding the behavior of hemodynamic parameters and changes in ventricular myocardium. The amendments will be quantified through the myocardial expression of molecular cell injury by the strength of inflammatory markers and oxidative stress and for assessing the levels of cellular apoptosis and impairment of alpha-actine. Will be studied 35 rats, separated into 5 groups, according to the time of induction of epidural anesthesia: Group 1: epidural before brain death, Group 2: epidural immediately after brain death, Group 3: epidural 20 minutes after brain death; Group 4: epidural 1 hour after brain death, and Group 5: control (brain death will be held but epidural anesthesia will not be held). The hemodynamic measurements and levels of plasma norepinephrine and epinephrine will be performed before and after the induction of brain death for six hours. After this period, the animals will be subjected to euthanasia by exsanguination and myocardial samples will be collected and prepared for analysis of IL-1beta, IL-6, TNF-alpha by the method of ELISA. The concentrations of Bcl-2, caspase-3, alpha-actine, ICAM, VCAM -1 and the polymers of adenosine diphosphate-ribose in heart tissue will be quantified by immunohistochemistry. (AU)