Dilutional Thrombocytopenia

By William Aird

It is not uncommon to here physicians refer to “dilutional” to explain a patient’s thrombocytopenia in hospital.

But the numbers just don’t add up (see graphic).

Our Hb/Hct and PLT counts are decreased proportionately when we lose blood (20% in this example), but we live much closer to the edge of anemia than we do to thrombocytopenia, so the threshold for developing dilutional anemia is MUCH lower than thrombocytopenia.