[Observational Study Protocol: Management of Anemia in Allogeneic Bone Marrow Donors]

Bone marrow harvesting from healthy voluntary donors for related or unrelated allogeneic transplantation is considered a safe procedure. However, its associated hematologic impact is well recognized, including a decrease in hemoglobin levels, with a potential need for transfusion support. In accordance with the policies of several donation centers, donors provide one unit of autologous blood that is reinfused after bone marrow collection, thereby avoiding the risks associated with allogeneic transfusion. Nevertheless, this practice carries risks such as the development of pre-bone marrow harvest anemia, infection or allergic transfusion reactions, and associated costs. The objective of this study is to optimize the management of peri-bone marrow harvest anemia and to identify which donors may or may not benefit from autologous blood unit collection. The study population will include allogeneic bone marrow donors from Instituto Português de Oncologia do Porto. The study is divided into two phases. Phase I (retrospective) involves collecting data from allogeneic bone marrow donors between 2013 and 2023; analyzing hemoglobin kinetics before and after harvesting, use of autologous transfusion, supplementation, and adverse events; discussing the results with the involved teams; and defining new strategies. Phase II (prospective) involves implementing the defined measures in bone marrow donors between January and June 2026 and comparing the resulting outcomes. It is expected that donor profiles that do or do not benefit from autologous blood unit collection will be identified, allowing optimization of clinical practice, reduction of risks and costs, and improvement of hematologic recovery.