How do you preserve blood?
Blood preservation techniques aim to maintain the viability and functionality of red blood cells (RBCs) and other blood components during storage. Here are some common blood preservation methods:
1. Refrigeration: Whole blood or blood components can be stored at refrigerated temperatures (2-6°C) for short periods, typically up to 35 days. This method helps slow down metabolic processes and preserve the viability of RBCs.
2. Additives: Preservative solutions containing various additives are used to extend the storage period of blood components, particularly RBCs. These additives include dextrose, adenine, and other nutrients that support the energy metabolism and prevent cell damage during storage.
3. Leukocyte Reduction: Leukocytes (white blood cells) can release harmful substances during storage that may shorten the lifespan of RBCs. Leukocyte reduction filters or centrifugation techniques can be used to remove a significant portion of white blood cells from the blood, thereby prolonging RBC storage.
4. Irradiation: Irradiating blood components with gamma radiation can prevent the proliferation of lymphocytes, which are types of white blood cells that can cause adverse immune reactions in recipients. Irradiation is commonly performed on blood products intended for immunocompromised patients or those at risk of transfusion-related graft-versus-host disease (GVHD).
5. Glycerol Freezing: For long-term preservation, blood components can be cryopreserved using glycerol as a cryoprotectant. Glycerol helps protect cells from damage during the freezing and thawing processes. Red blood cells preserved through cryopreservation can be stored at ultra-low temperatures (-80°C or lower) for several years.
6. Plasma Fractionation: Plasma, the liquid component of blood, can be separated into various fractions containing specific proteins and clotting factors. These plasma derivatives, such as albumin, immunoglobulins, and clotting factor concentrates, can be stored and used for therapeutic purposes.
Proper blood collection, processing, storage, and transportation are crucial to ensure the safety and efficacy of blood transfusions. Blood banks and transfusion services follow strict protocols and quality control measures to maintain the integrity and viability of blood products throughout their shelf life.