Systematic Intraoperative Cell Salvage in On-Pump Cardiac Surgery Within a Mature Patient Blood Management Programme

The goal of this observational study is to learn if cell salvage lowers the need for donor blood in adults having planned heart surgery with a heart-lung machine. Cell salvage collects the blood a person loses during surgery, cleans it and gives it back to them. The hospital already has a programme to lower blood loss and the need for donor blood. Since January 2025, it uses cell salvage in all eligible people. The main question it aims to answer is: \- Do fewer participants need donor red blood cells during their hospital stay when cell salvage is used in everyone? Researchers will compare people who had surgery with cell salvage from January 2025 to: * people who had surgery in 2023 and 2024, before this change * people who had surgery from January 2025 without cell salvage to see if fewer of them need donor blood. Researchers will also look at the use of other blood products, red blood cell levels, complications, time in hospital, and survival 12 months after surgery. Participants will have their usual surgery and care. The study does not change their treatment. Researchers will collect information from their medical records, from surgery up to 12 months later.

Inclusion Criteria: * Adults aged 18 years or older * Elective on-pump cardiac surgery at Unidade Local de Saúde Gaia/Espinho, including isolated or combined coronary artery bypass grafting, valve and aortic procedures * Surgery performed within the defined period for each group (Group B: January 2023 to December 2024; Groups A and C: January 2025 to December 2027) Exclusion Criteria: * Emergency or urgent procedures * Off-pump procedures * Patients who declined allogeneic blood transfusion (eg, Jehovah's Witnesses) * Pregnant or lactating patients * Known haematological malignancy, active or under treatment * Diagnosed inherited coagulopathy requiring specialist haematology follow-up (eg, haemophilia, inherited von Willebrand disease)