Selected blood coagulation parameters during extracorporeal circulation.
We investigated selected coagulation parameters in 13 patients who had undergone open heart surgery with extracorporeal circulation (ECC). During ECC factor XIIa increased considerably to 38%. This may lead to intravascular coagulation, which is however inhibited during ECC by the administered heparin. The C1-inhibitor activity decreased to 12% during ECC, this decrease was considerably greater and lasted longer than the decrease of the C1-inhibitor concentration, which declined to 59%. The levels of the other coagulation factors I, II, V, VII, X, XII, antithrombin III, alpha 2-antiplasmin and platelets decreased to 50-60%. The latter was predominantly due to hemodilution at the beginning of ECC. We assume that the critical period for the coagulation system in ECC appears when ECC is discontinued. At this point we have a high factor XIIa level and a low C1-inhibitor activity so that intravascular coagulation (DIC) may occur because then the inhibitory effect of heparin is neutralized by protamine.
D000328:Adult; D001777:Blood Coagulation; D001779:Blood Coagulation Factors / Q000032:analysis; D006348:Cardiac Surgical Procedures; D001026:Coronary Artery Bypass; D005112:Extracorporeal Circulation; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D006350:Heart Valve Prosthesis; D006400:Hematocrit; D006801:Humans; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D010976:Platelet Count; D011480:Protease Inhibitors / Q000097:blood
D001779:Blood Coagulation Factors; D011480:Protease Inhibitors; D005340:Fibrinogen