Washed red blood cells are red blood cells which have had most of the plasma, platelets and

white blood cells White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

removed and replaced with saline or another type of preservation solution. The most common reason for using washed red blood cells in transfusion medicine is to prevent the recurrence of severe

allergic transfusion reaction An allergic transfusion reaction is when a blood transfusion results in allergic reaction. It is among the most common transfusion reactions to occur. Reported rates depend on the degree of active surveillance versus passing reporting to the blood ...

s that do not respond to medical treatment. The usual cause of these allergic reactions is proteins in the donor plasma. 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. These can include automated or manual methods. They can use centrifugation or centrifugation-free methods. 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

s. 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 Haptoglobin (abbreviated as Hp) is the protein that in humans is encoded by the ''HP'' gene. In blood plasma, haptoglobin binds with high affinity to ''free'' hemoglobin released from erythrocytes, and thereby inhibits its deleterious oxidative ...

in people with IgA and haptoglobin deficiency have been suggested to have a causal relationship with the allergic reaction.

Cytokine Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...

s and

chemokine Chemokines (), or chemotactic cytokines, are a family of small cytokines or signaling proteins secreted by cells that induce directional movement of leukocytes, as well as other cell types, including endothelial and epithelial cells. In additio ...

s, which accumulate during the storage of blood components, have also been suggested as causative agents. 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.

Reduction in transfusion-related complications

In neonates transfusion has been associated with an increased risk of serious side-effects including: *

Necrotising enterocolitis Necrotizing enterocolitis (NEC) is a devastating intestinal disease that affects premature or very low birth weight infants.Gephart S.M., Quinn M. A call to action to fight for equity and end necrotizing enterocolitis disparities. ''Adv. Neonata ...

(NEC) * Intraventricular haemorrhage (IVH) *

Retinopathy of prematurity Retinopathy of prematurity (ROP), also called retrolental fibroplasia (RLF) and Terry syndrome, is a disease of the eye affecting prematurely born babies generally having received neonatal intensive care, in which oxygen therapy is used due to ...

(ROP) * Chronic lung disease (CLD) * Death Transfusion-related immune modulation has been thought to be the underlying mechanism. Washing red cells has been thought to be one way of potentially decreasing the risk of theses transfusion-related side-effects. However, in neonates, there is insufficient evidence to say whether washing red cells has any effect.

Storage

Once red blood cells have been washed they can only be kept for up to a day.

References

Blood cells {{treatment-stub Transfusion medicine