Biocompatible Versus Non-coated Extracorporeal Circuits in Cardiac Surgery

The aim of the present strudy is to investigate whether the use of biocompatible extracorporeal circulation circuits with a special hydrophilic polymer coating without heparin causes a reduction in the activation of the coagulation mechanism and the formation of microthrombi in the circuit tubing. A total of 50 patients undergoing cardiac surgery with extracorporeal circulation will be randomized in two groups using a computer-generated algorithm. The first group (study group) will undergo cardiac surgery with a specialized biocompatible circuit with a hydrophilic coating, while the control group will be operated with the conventional non-coated extracorporeal circulation circuit. During the period of extracorporeal circulation, blood samples will be taken at predetermined times which will be analyzed with the ELISA technique to determine the levels of prothrombin fragments 1+2 (F1+2), thrombin/antithrombin complex (TAT) as well as platelet factor P-selectin. Moreover, sections of the circuit tubes will be examined under electron microscopy for quantitative evaluation of microthrombi detected on the walls. The expected outcome of the study is to establish, with the use of specific biochemical markers and electron microscopy the protective effect of biocompatible coated extracorporeal circulation circuits on the coagulation mechanism and platelet activation.