A hemolyzed sample will cause falsely increased levels of each of the following EXCEPT

A hemolyzed sample will cause falsely increased levels of each of the following EXCEPT

• A. Sodium
• B. Potassium
• C. Phosphate
• D. Magnesium

Answer: (A)

Hemolysis releases the contents of red blood cells into the serum, so substances that are highly concentrated inside cells rise in the sample. Potassium is abundant inside RBCs, so when cells break open, potassium floods into the plasma and appears falsely high. Phosphate is also abundant intracellularly, leading to a raised serum phosphate on a hemolyzed sample. Magnesium is present in higher amounts inside cells as well, so it can falsely increase too. Sodium, however, is mainly extracellular and RBCs contain relatively little sodium, so rupturing cells don’t push the serum sodium up. In fact, any change in sodium is usually negligible or may even trend downward, not upward. So sodium is the one that would not show a falsely increased value.

Hemolysis releases the contents of red blood cells into the serum, so substances that are highly concentrated inside cells rise in the sample. Potassium is abundant inside RBCs, so when cells break open, potassium floods into the plasma and appears falsely high. Phosphate is also abundant intracellularly, leading to a raised serum phosphate on a hemolyzed sample. Magnesium is present in higher amounts inside cells as well, so it can falsely increase too. Sodium, however, is mainly extracellular and RBCs contain relatively little sodium, so rupturing cells don’t push the serum sodium up. In fact, any change in sodium is usually negligible or may even trend downward, not upward. So sodium is the one that would not show a falsely increased value.