Phlebotomy Specimen Processing and Handling Questions and Answers

Question 1

A phlebotomist has just drawn a serum separator tube (SST) for a chemistry panel. What is the correct minimum time the tube should be allowed to clot before centrifugation?

Accepted Answer

30 minutes

Answer

Serum separator tubes require adequate time for complete clot formation to ensure proper separation of serum from cellular components during centrifugation. The standard recommended minimum clotting time is 30 minutes at room temperature.

Question 2

Which of the following would be a valid reason for a laboratory to reject a blood specimen?

Accepted Answer

The specimen was collected in a tube with an expired date.

Answer

Laboratories have strict criteria for specimen acceptance to ensure test accuracy. Using an expired collection tube is a reason for rejection because the vacuum may be insufficient and the additives may have degraded, compromising the specimen's integrity.

Question 3

A test for bilirubin levels has been ordered. What is the most critical handling requirement for this specimen immediately after collection?

Accepted Answer

Protect the tube from light.

Answer

Bilirubin is a photosensitive analyte, meaning it breaks down when exposed to light. To ensure accurate test results, the specimen must be protected from light by wrapping it in aluminum foil or placing it in an amber-colored tube immediately after collection.

Question 4

A phlebotomist must prepare a specimen for transport to a reference lab that requires chilled handling. What is the proper technique for chilling the specimen?

Accepted Answer

Submerging the tube in a mixture of crushed ice and water.

Answer

For proper chilling, the specimen tube must be fully surrounded by the cooling medium to ensure rapid and consistent temperature reduction. A slurry of crushed ice and water provides the most effective contact with the entire surface of the tube.

Question 5

When balancing a centrifuge for spinning blood tubes, which principle must be followed?

Accepted Answer

Tubes of the same size and fill volume must be placed directly opposite each other.

Answer

To prevent damage to the centrifuge and ensure proper specimen separation, the rotor must be balanced. This is achieved by placing tubes of equal size, shape, and volume in opposite positions to distribute the weight evenly.

Phlebotomy Practice Test Practice Test

Phlebotomy Practice Test Practice Test

Phlebotomy Specimen Processing and Handling Questions and Answers