This is a universal measure to remove granulocytes and lymphocytes from the blood prior to storage. Australian PRBCs are now routinely leukodepleted. In the olden days, one would run the undepleted PRBCs through a filter at the bedside.
Some believe that there is a good reason we spend money on this practice, even though there is no evidence to support the "extended indications" for leukoreduction.
Specifics of this issue were discussed in Question 29.2 from the first paper of 2010.
Indications for leukodepleted blood products
Prior to the introduction of universal leukoreduction, there were groups of patients who were known to benefit from such products. The hard indications for leukoreduced blood products are as follows:
- People who are likely to receive a massive transfusion
- People in whom being platelet refractory would be problematic
- People at risk of febrile reaction (eg. those alloimmunised during pregnancy)
- People at risk of severe CMV infection (eg. BMT recipients)
Currently, there is no evidence that the practice of routinely leukoreducing all packed RBCs is improving mortality and morbidity. Certainly, there is no evidence that the practice has any influence on mortality outside of its narrow range of indications. This has prompted some people to question whether this practice is a cost-effective public health measure. And others to question whether the reintoduction of nondepleted products would result in some sort of haematological apocalypse.