ASCP Phlebotomy

Question 1

What shade of tube should be used when taking a sample to check blood alcohol levels?

Accepted Answer

Gray.

Answer

Gray-top tubes are used for blood alcohol levels because they contain sodium fluoride, which acts as an antiglycolytic agent. Sodium fluoride prevents glucose metabolism by red blood cells, ensuring that the alcohol concentration remains stable and accurate over time. These tubes also typically contain potassium oxalate as an anticoagulant.

Question 2

What should be added to a sample if it needs to be diluted?

Accepted Answer

Diluent.

Answer

A diluent is a substance, typically a liquid, used to reduce the concentration of a solution or suspension. When a blood sample needs to be diluted for specific laboratory tests, a precise amount of diluent is added to achieve the correct concentration for accurate analysis. Preservatives and anticoagulants serve different functions related to sample integrity.

Question 3

What component of blood is potassium EDTA able to bind to?

Accepted Answer

Calcium.

Answer

Potassium EDTA (Ethylenediaminetetraacetic acid) acts as an anticoagulant by binding to calcium ions in the blood. Calcium is a crucial cofactor required for the coagulation cascade, and by chelating (binding) free calcium, EDTA effectively prevents the blood from clotting. This makes EDTA tubes suitable for hematology tests where whole blood is needed.

Question 4

Which of the following can affect a blood sample if the patient refuses to fast when instructed to do so?

Accepted Answer

Increasing its turbidity.

Answer

If a patient fails to fast as instructed before a blood draw, the presence of recently ingested fats (lipids) in the bloodstream can cause the serum or plasma to appear cloudy or milky. This condition is known as lipemia, and the increased turbidity can interfere with various laboratory tests, leading to inaccurate or falsely elevated results for certain analytes.

Question 5

What should you do if you realize that a patient's name is spelled differently on the requisition and the patient's armband?

Accepted Answer

Visit with your manager to verify the information and have it corrected.

Answer

Patient identification is paramount in healthcare. If there is any discrepancy between a patient's name on the requisition and their armband, the phlebotomist must not proceed with the draw. The correct action is to immediately report the discrepancy to a manager or nursing staff to verify the patient's identity and have the information corrected, preventing potential medical errors.

ASCP Phlebotomy Technician Exam Practice Test

ASCP Phlebotomy Technician Exam Practice Test

ASCP Phlebotomy