Electric Polarization of Red Blood Cells : A Cohort Study to Assess the Erythrocytes Membrane Integrity Through Charge Conservation, Following Cardiac Surgery. (Polaris)

An immediate perioperative parameter that assess the integrity of the Erythrocytes Membrane and therefore their structural quality isn't available in clinical practice and medical diagnostics except through indirect clinical biochemical tests or through the scanning electron microscope. The red blood cell (RBC) membrane contains proteins and glycoproteins embedded in a fluid lipid bilayer that confers viscoelastic behavior. Sialylated glycoproteins of the RBC membrane are responsible for a negatively charged surface which creates a repulsive electric zeta potential (ζ) between cells. These charges help prevent the interaction between RBCs and the other cells and especially between each other. The zeta potential is a physical property which is exhibited by all particles in suspension. The development of a net charge on any particle affects the distribution of ions in the surrounding interfacial region resulting in an increased concentration of counter ions of opposite charge to that of the particle, close to the surface. In this context we present a new parameter that studies the interactions of the Erythrocytes membrane treated with positive ions and their maintenance of the charge. We compared the measured polarization values with the Erythrocyte Sedimentation Rate (ESR), expression of speed with which RBCs tend to settle inside a particular graduated capillary called Westergren's tube and Plasma Free Hemoglobin (pFHb).

Inclusion Criteria:Elective, primary cardiac surgery for Minimally invasive cardiac surgery (MICS) group, thirty Mitral Valve Surgery (MVS) in Right Anterolateral Mini-thoracotomy and Conventional cardiac surgery (CCS) group, thirty Coronary Arterial Bypass Grafting (CABG) In Full sternotomy.Exclusion Criteria:Patients were excluded if they presented abnormal plasma lactate levels (>2 mmol/L) before entering Cardiopulmonary bypass (CPB), renal or liver failure, obesity, uncompensated diabetes, autoimmune disease, active infection, any immunosuppressant therapy, or coagulation disorder. Patients undergoing surgery with circulatory arrest or having preoperative hematocrit (Hct) <27% were also excluded.