title: Relationship of fibrinolysis and platelet function to bleeding after cardiopulmonary bypass.
abstract: In order to study the effects of cardiopulmonary bypass (CPB) on fibrinolysis and platelet function and the possible relationship of these effects on post-operative blood loss, 127 patients undergoing CPB were examined. There was a significant reduction in the median levels of fibrinogen, plasminogen, alpha 2-antiplasmin, fibrinolytic potential and platelet aggregation during CPB (P < or = 0.001). Median levels of soluble fibrin, fibrinogen degradation products, D-dimer and PAI-1 were increased, while the level of t-PA activity remained constant. Post-CPB levels of fibrinogen and plasminogen correlated negatively with blood loss (P = 0.003 and P < 0.001, respectively) and interestingly, lower levels of alpha 2-antiplasmin and higher levels of t-PA activity before CPB were associated with greater blood loss after CPB (P < 0.001 and P = 0.004, respectively). Better pre-CPB platelet function correlated with lower levels of D-dimer before and after CPB. As expected, haemodilution had a significant effect on fibrinolytic and coagulation parameters post-CPB; the greater the haemodilution, the more the concentration of fibrinogen, plasminogen and alpha 2-antiplasmin fell post-CPB and the greater the blood loss. The increase in PAI-1 levels intra-CPB appeared to result in mean t-PA activity remaining unchanged 1 h post-CPB. Post-CPB increases in soluble fibrin were paralleled by increases in fibrinogen degradation products and D-dimer, suggesting that intra-operative contact activation is related to activation of the fibrinolytic system. The present findings indicate the greater the fibrinolytic activation, the greater the post-CPB blood loss.
authors.affiliation: Department of Haematology, Prince Charles Hospital, Brisbane, Queensland, Australia.
authors.forename: M J
authors.initials: MJ
authors.lastname: Ray
authors.forename: N A
authors.initials: NA
authors.lastname: Marsh
authors.forename: G A
authors.initials: GA
authors.lastname: Hawson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000502:physiology*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D005260:Female; D005337:Fibrin / Q000378:metabolism; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005342:Fibrinolysis; D006438:Hemodilution; D006470:Hemorrhage / Q000097:blood* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010958:Plasminogen / Q000378:metabolism; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism; D010974:Platelet Aggregation; D010959:Tissue Plasminogen Activator / Q000378:metabolism; D000979:alpha-2-Antiplasmin / Q000378:metabolism
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; D017395:Plasminogen Activator Inhibitor 1; D000979:alpha-2-Antiplasmin; D005337:Fibrin; D005340:Fibrinogen; D010958:Plasminogen; D010959:Tissue Plasminogen Activator