Does the Use of Anticoagulants During Cardiopulmonary Bypass Prevent Microthrombosis Formation Completely?

Aim: This study examined whether heparin use during cardiopulmonary bypass (CBP) completely prevents microthrombus formation. Materials and Methods: The coagulation systems of 42 patients undergoing open heart surgery were evaluated by collecting blood specimens for factor (F) II, V, VII, and X, antithrombin-III (AT-III), protein C, protein S, fibrinogen, D-dimer, PT, aPTT and complete blood count investigation before induction of anesthesia, half an hour after start of CBP, following sternum closure and on postoperative day 1. Liver, kidney and neurocognitive functions were also evaluated. Results: FII, FV, FVII, FX, AT-III and protein C values decreased significantly during CBP compared to preoperative values, and then gradually increased. Protein S values increased significantly during CBP and subsequently decreased to preoperative levels. Fibrinogen levels fluctuated, while D-dimer, PT ve aPTT increased during CBP. Hemoglobin, hematocrit and platelet values also decreased during CBP, and then rose gradually. No significant kidney, liver or neurocognitive function impairment was determined. Conclusion: Coagulation factors decreasing during CBP and then rising may be related to hemodilution. However, the increase in D-dimer shows that thrombus formation occurs during CBP, although this is not clinically significan