Optimal Cardiopulmonary Bypass and Anticoagulation Management Strategies in Obese Patients Undergoing Cardiac Surgery

Inclusion criteria

• Obese patients (BMI ≥ 30kg/m2)
• Planned cardiac surgery
• Age ≥ 18 years

Exclusion criteria

• Permanent pacemaker
• Known intolerance to protamine
• Known or suspected allergy to the used antifibrinolytic agent
• Refusal to receive blood products
• Planned off pump coronary artery bypass
• Planned peri-operative use of desmopressin
• Known Heparin-induced thrombocytopenia
• Known deficiency in protein C, protein S, antithrombin or homozygous factor V Leiden
• Known congenital bleeding disorders
• Current endocarditis
• Planned hypothermic circulatory arrest (<28C)
• Two or more cardiac surgery procedures
• Emergency cardiac surgery procedures (medically required within 24hours of presenting with acute symptoms)
• Planned CPB priming with red blood cells
• Any known autoimmune disease
• Any history of stroke or non-coronary thrombotic disorders including deep venous thrombosis and pulmonary embolism
• Significant (≥50%) carotid artery stenosis
• Patient dosed with low molecular weight Heparin less than 24h before surgery
• Females of childbearing potential who are pregnant, breast-feeding or intend to become pregnant or are not using adequate contraceptive methods
• Confirmed ST elevation myocardial infarction (STEMI) within 7 days
• Pre-operative platelet count <100,000/microliter
• Anaemia (Hematocrit <32% for females, <35%for males)
• Dosed with clopidogrel or ticagrelor within the last 5 days prior to surgery, or prasugrel within 7 days
• Dosed with GPIIb/IIIa receptor blockers (Abciximab, Tirofiban, Eptifibatide) ≤ 24 hours prior to surgery
• International ratio (INR) >1.5 on the day of surgery in patients treated with vitamin K antagonist
• Liver dysfunction (aspartate aminotransferase (AST) or alanine aminotransferase (ALT) increased ≥ 2-fold above the upper limit of local laboratory normal ranges)
• Renal failure (creatinine ≥ 175 micromol/L or dialysis)
• Current thromboembolic disease other than myocardial infarct
• Patients who have pre-donated autologous blood
• Patient presenting with a resistance to Heparin