A prospective randomized study comparing therapy guided by the cardiac index derived from the analysis of blood pressure curve and standard therapy of hemodynamic resuscitation in cardiac surgery patients

Abstract

The current managment of hemodynamic resuscitation of the patients that undergo cardiac surgery present obstacles that begin in the operating room. Due to host factors and the opertation itself, some patients can present hypotention, vascular dilation, vasoplegia and cardiac output. These changes are responsible for a significant impact in morbidity and can result in organic disfunction and mortality. The early treatment based on hemodynamic goals of high risk patients is fundamental to reduce the developement of organic disfunctions, reducing the ICU length of stay and mortality. The Flo Trac/Vigileo is a minimally invasive monitor that calculates the cardiac índex throught the analysis of the blood pressure curve, without any previous calibration. The easy handling and the need of one arterial acess are other advantages it presents. There is a lack of clinical trials that compare the eficiency of the therapy that applies hemodynamic resuscitation guided by the cardiac índex through the blood pressure curve analysis (Flo Trac/Vigileo) and the gold standard therapy used in cardiac surgery patients. The aim of this study is to compare an optimizing hemodynamic strategy based on the use of the minimally invasive cardiac índex analysis versus the gold standard hemodynamic resuscitation therapy used in cardiac surgery patients, evaluating the clinical evolution and hemodynamics. METHODOLOGY: 200 patients submitted to cardiac surgery in the Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo, will be studied in a prospective and randomized manner. After filling in inclusion criteria patients will be randomized in a 1:1 ratio for cardiac index group or control group. The protocol will be initiated during anesthesia induction and will be maintained through 8 hours of postoperative period. The sample size was determined using a 2-sided statistical tests, a significant level of 5, a power of 80% and a 20% difference between groups. The results will be submitted through statistical analysis following the standards of this institution. (AU)