An observational study comparing two systems of perioperative blood recovery in cardiac surgery, one system allowing red blood cell reinfusion and one system allowing red blood cell and platelet reinfusion. The objective is to evaluate whether platelet recovery provides better quality of hemostasis during and after surgery, improving transfusion savings, and whether it reduces postoperative complications and the length of stay in the intensive care unit and in the hospital.

° Primary outcome of the study : The primary outcome of the study is to compare the evolution of perioperative platelet count based on the type of blood recovery used, either SAME or Cell-Saver.

The main outcome measure is the difference between the preoperative and immediate postoperative platelet counts (delta platelet) for each patient between the SAME and Cell-Saver groups.

° Secondary outcomes of the study:

The secondary outcomes are to evaluate, from the preoperative period until day 28 postoperatively:

• The post-operative platelet count between days 1 and 5
• The frequency of perioperative and postoperative transfusions, including the number and type of blood products transfused
• The use of derivative medications (fibrinogen, prothrombin complex concentrates)
• The volume of postoperative bleeding
• The frequency of postoperative events (infectious, renal, thromboembolic, hemorrhagic)
• The length of stay in the intensive care unit and in the hospital
• The frequency of treatment for postoperative anemia with iron or erythropoiesis-stimulating agents.

Inclusion Criteria:

• Scheduled cardiac surgery under cardiopulmonary bypass with a predicted duration of more than 2 hours, or surgery of the aortic arch, redo surgery, multiple aorto-coronary bypasses (>2), or combined surgery (valvular and coronary).

Exclusion Criteria:

• Pre-existing constitutional or acquired bleeding disorder (hemophilia A or B, von Willebrand disease, myelodysplastic/myeloproliferative syndrome)
• Patients with sepsis, a malignant tumor at the surgical site, or contamination of recovered blood with biological fluids/antiseptics/distilled water/local antibiotics/hemostatic agents.
• Organ transplantation and planned circulatory support in the preoperative period
• Uni-bi-ventricular artificial heart
• Reoperation in a patient already included in the study
• Patient refusing blood transfusion
• Pregnant women
• Legally Protected adults

Adult patients treated by the cardiac surgery department of Nantes University Hospital who undergo a cardiovascular procedure with cardiopulmonary bypass considered to be at high risk for bleeding; (prolonged cardiopulmonary bypass >2 hours, aortic arch surgery, history of redo cardiac surgery, combined surgery, multiple portocoronary bypasses). Procedures for which a perioperative blood recovery device (SAME or Cell-Saver) has been used, with the choice of the blood recovery technique at the discretion of the medical team.