Washed red blood cells
Washed red blood cells are red blood cells which have had most of the plasma, platelets and white blood cells removed and replaced with saline or another type of preservation solution.[1][2] The most common reason for using washed red blood cells in transfusion medicine is to prevent the recurrence of severe allergic transfusion reactions that do not respond to medical treatment. The usual cause of these allergic reactions is proteins in the donor plasma.[3] These proteins are removed by the process of washing the red blood cells.
Methods of washing red cells
There are multiple methods of washing red cells.[2] These can include automated or manual methods. They can use centrifugation or centrifugation-free methods.[2] The red cells can be re-suspended in saline or other types of special preservative solutions for red cells e.g. SAG-M.
Medical Uses
Prevention of recurrence of severe allergic reactions
The most common reason for using washed red blood cells in transfusion medicine is to prevent the recurrence of severe allergic transfusion reactions. The allergen is usually a protein in the plasma that is removed by the process of washing the red blood cells. Various proteins, such as antibodies directed against IgA or haptoglobin in people with IgA and haptoglobin deficiency have been suggested to have a causal relationship with the allergic reaction.[4][3] Cytokines and chemokines, which accumulate during the storage of blood components, have also been suggested as causative agents.[3][5] However, the literature is scarce and conflicting as passive infusion of anti-IgA antibodies in to recipients has not been found to cause an allergic reaction.[4][3]
Reduction in transfusion-related complications
In neonates transfusion has been associated with an increased risk of serious side-effects[5][6] including:
- Necrotising enterocolitis (NEC)
- Intraventricular haemorrhage (IVH)
- Retinopathy of prematurity (ROP)
- Chronic lung disease (CLD)
- Death
Transfusion-related immune modulation has been thought to be the underlying mechanism.[6] Washing red cells has been thought to be one way of potentially decreasing the risk of theses transfusion-related side-effects.[6] However, in neonates, there is insufficient evidence to say whether washing red cells has any effect.[6]
References
- Albiston B (October 2011). "Guideline for Washed Red Blood Cells in Nova Scotia" (PDF). Nova Scotia.
- Lu M, Lezzar DL, Vörös E, Shevkoplyas SS (2019). "Traditional and emerging technologies for washing and volume reducing blood products". Journal of Blood Medicine. 10: 37–46. doi:10.2147/JBM.S166316. PMC 6322496. PMID 30655711.
- Hirayama F (February 2013). "Current understanding of allergic transfusion reactions: incidence, pathogenesis, laboratory tests, prevention and treatment". British Journal of Haematology. 160 (4): 434–44. doi:10.1111/bjh.12150. PMC 3594969. PMID 23215650.
- Sandler SG, Eder AF, Goldman M, Winters JL (January 2015). "The entity of immunoglobulin A-related anaphylactic transfusion reactions is not evidence based". Transfusion. 55 (1): 199–204. doi:10.1111/trf.12796. PMID 25066014.
- Schmidt AE, Refaai MA, Kirkley SA, Blumberg N (2016-08-22). "Proven and potential clinical benefits of washing red blood cells before transfusion: current perspectives". International Journal of Clinical Transfusion Medicine: 79–88. doi:10.2147/ijctm.s101401. Retrieved 2019-01-25.
- Keir AK, Wilkinson D, Andersen C, Stark MJ (January 2016). "Washed versus unwashed red blood cells for transfusion for the prevention of morbidity and mortality in preterm infants". The Cochrane Database of Systematic Reviews (1): CD011484. doi:10.1002/14651858.cd011484.pub2. PMID 26788664.
- Handin RI, Lux SE, Stossel TP (2003). Blood: Principles and Practice of Hematology. Lippincott Williams & Wilkins. p. 2034. ISBN 9780781719933.