Factors associated with excessive bleeding in cardiopulmonary bypass patients: a nested case-control study

<p>Abstract</p> <p>Introduction</p> <p>Excessive bleeding (EB) after cardiopulmonary bypass (CPB) may lead to increased mortality, morbidity, transfusion requirements and re-intervention. Less than 50% of patients undergoing re-intervention exhibit surgical sources of bleeding. We studied clinical and genetic factors associated with EB.</p> <p>Methods</p> <p>We performed a nested case-control study of 26 patients who did not receive antifibrinolytic prophylaxis. Variables were collected preoperatively, at intensive care unit (ICU) admission, at 4 and 24 hours post-CPB. EB was defined as 24-hour blood loss of >1 l post-CPB. Associations of EB with genetic, demographic, and clinical factors were analyzed, using SPSS-12.2 for statistical purposes.</p> <p>Results</p> <p>EB incidence was 50%, associated with body mass index (BMI)< 26.4 (25–28) Kg/m², (<it>P </it>= 0.03), lower preoperative levels of plasminogen activator inhibitor-1 (PAI-1) (<it>P </it>= 0.01), lower body temperature during CPB (<it>P </it>= 0.037) and at ICU admission (<it>P </it>= 0.029), and internal mammary artery graft (<it>P </it>= 0.03) in bypass surgery. We found a significant association between EB and 5G homozygotes for PAI-1, after adjusting for BMI (F = 6.07; <it>P </it>= 0.02) and temperature during CPB (F = 8.84; <it>P </it>= 0.007). EB patients showed higher consumption of complement, coagulation, fibrinolysis and hemoderivatives, with significantly lower leptin levels at all postoperative time points (<it>P </it>= 0.01, <it>P </it>< 0.01 and <it>P </it>< 0.01).</p> <p>Conclusion</p> <p>Excessive postoperative bleeding in CPB patients was associated with demographics, particularly less pronounced BMI, and surgical factors together with serine protease activation.</p

Antiphospholipid syndrome; its implication in cardiovascular diseases: a review

Antiphospholipid syndrome (APLS) is a rare syndrome mainly characterized by several hyper-coagulable complications and therefore, implicated in the operated cardiac surgery patient. APLS comprises clinical features such as arterial or venous thromboses, valve disease, coronary artery disease, intracardiac thrombus formation, pulmonary hypertension and dilated cardiomyopathy. The most commonly affected valve is the mitral, followed by the aortic and tricuspid valve. For APLS diagnosis essential is the detection of so-called antiphospholipid antibodies (aPL) as anticardiolipin antibodies (aCL) or lupus anticoagulant (LA). Minor alterations in the anticoagulation, infection, and surgical stress may trigger widespread thrombosis. The incidence of thrombosis is highest during the following perioperative periods: preoperatively during the withdrawal of warfarin, postoperatively during the period of hypercoagulability despite warfarin or heparin therapy, or postoperatively before adequate anticoagulation achievement. Cardiac valvular pathology includes irregular thickening of the valve leaflets due to deposition of immune complexes that may lead to vegetations and valve dysfunction; a significant risk factor for stroke. Patients with APLS are at increased risk for thrombosis and adequate anticoagulation is of vital importance during cardiopulmonary bypass (CPB). A successful outcome requires multidisciplinary management in order to prevent thrombotic or bleeding complications and to manage perioperative anticoagulation. More work and reporting on anticoagulation management and adjuvant therapy in patients with APLS during extracorporeal circulation are necessary