Q: Patient's platelet count suddenly dropped from 283 k/uL to 25 k/uL. Patient is clinically stable and you expect pseudothrombocytopenia. What would be your instruction to nursing staff while repeating lab?
Answer: Send second blood sample with 'blue top'
Most pseudothrombocytopenia has been reported in association with the use of ethylenediaminetetraacetic acid (EDTA) as an anticoagulant. A second sample run with a different anticoagulant such as citrate (blue top tube) usually helps to rule out the error.