Prophylatic use of desmopressin in valvular cardiac surgeries to decrease perioperative bleeding

• Grant number: 14/03785-1
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2015
• End date: January 31, 2017
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Filomena Regina Barbosa Gomes Galas
• Grantee: Filomena Regina Barbosa Gomes Galas
• Host 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
• Associated researchers: Giovanne Santana de Oliveira ; Ludhmila Abrahão Hajjar

Abstract

Patients with significant valve disorders present coagulopathy induced by mechanical effects (valvular stenosis or valvular insufficiency). Besides, these populations need prophylactic use of antiplatelet drugs due to myocardial remodeling and antiarrhythmic conditions that may be associated. Patients with severe aortic stenosis may also acquire vonWillebrand disease type 2A due to proteolysis of vonWillebrand factor. Despite the presented facts, the treatment of these valve disorders often requires cardiac surgery with extracorporeal circulation. On average, 50 to 60% of patients undergoing cardiac surgery receive blood tranfusions. Blood cell transfusion is an independent risk factor for increased morbidity and mortality in critically ill patients. The use of desmopressin seems beneficial only in patients with congenital or acquired platelet dysfunction. In general population, such use is not validated due to inconclusive results of researches. Objectives: Evaluate the use of desmopressin as a hemostatic agent capable of reducing excessive bleeding in cardiac valve surgeries with extracorporeal circulation. Clinical and laboratory evaluation of blood coagulation with prophylactic use of desmopressin in cardiac valve surgeries. Evaluate reduction of blood components transfusions with prophylactic use of desmopressin. Method: This study is a clinical, prospective, randomized and double-blind intervention trial. It will be performed in the surgical center and intensive care unit of the Heart Institute (InCor) from Faculty of Medicine, University of São Paulo (FMUSP), on 100 patients undergoing cardiac surgery to repair valve defects, who satisfy inclusion and exclusion criteria. Inclusion criteria: a) Cardiac valve surgeries with extracorporeal circulation in patients older than 18 years; b) Read and signed Free and Clear Up Consentiment Term by responsible ones; c) Preanesthetic assessment and pre-operatory exams in accordance with study methodology. Exclusion criteria: Younger than 18 years; active infection; creatinin>2 mg/Dl; cardiac reoperation; body mass index >35; ejection fraction 40%; hematocrit<35%; previously known non - pharmacological coagulopathy; antiplatelet therapy use until 10 days before surgery (except acetylsalicylic acid and enoxaparin that may be used in prophylactic doses until 24h before surgery); use of mechanical valve prosthesis; severe associated cardiopathies; absence of signed Free and Clear Up Consentiment Term; isolated or associated procedures of myocardial revascularization. In preanesthetic visit, there will be patient assessment of the criteria described in study methodology. In anesthetic induction, a blood sample will be taken to analyze hemostatic function (T0). After extracorporeal circulation and heparin reversion, the randomized patients in desmopressin group will receive, in a prophylactic way, DDAVP (0,3µg/kg) diluted to 100 mL of saline solution and the control group will receive just 100 mL of saline solution. After two hours of desmopressin administration, a new blood sample will be taken (T1) such as after 24h (T2). Patients will be followed until hospital discharge or 28 days after surgery, regarding allogeneic transfusion needs, reoperation and thromboembolic events. (AU)