American Board of Internal Medicine (ABIM) Certification Practice Exam

Which method is commonly used to reduce potassium levels in blood products for certain patients?

1. Washing of blood products

2. Cryopreservation

3. Irradiation

4. Filtration

The correct answer is: Washing of blood products

Washing of blood products is a method commonly employed to reduce potassium levels in blood products, particularly for certain vulnerable patient populations, such as those at risk for transfusion-related hyperkalemia. When blood products are stored, particularly red blood cells, potassium can leak out of the cells into the storage solution, leading to elevated potassium levels in the transfusion. By washing the blood products—typically with a saline solution—most of the plasma, which contains high levels of potassium and other additives, is removed. This process helps to lower the overall potassium concentration in the final product, making it safer for patients who are susceptible to the complications associated with hyperkalemia, such as those with renal failure or certain cardiac conditions. While the other methods listed—cryopreservation, irradiation, and filtration—serve specific purposes like preserving cellular viability, preventing transfusion-related graft-versus-host disease, and removing leukocytes or pathogens, they do not directly address the issue of reducing potassium levels in blood products.