Specimen Processing and Handling Flashcards

Which of the following is a pre-analytical error that affects specimen quality?

Answer: Collecting a specimen from an IV line without proper protocol

Collecting a specimen from an IV line without proper protocol (e.g., not discarding the first few mL) is a pre-analytical error that dilutes the specimen and compromises results.

How should aliquots be labeled when dividing a specimen into multiple tubes?

Answer: Each aliquot must be labeled with the same patient information as the original

Each aliquot must carry the same complete patient identification as the primary specimen to ensure traceability and prevent mix-ups.

The recommended centrifuge speed for most routine serum or plasma separations is:

Answer: 1,000–2,000 × g for 10 minutes

Most routine specimens are centrifuged at 1,000–2,000 × g for 10 minutes to achieve adequate separation without damaging cellular components.

Which specimen requires protection from light during transport and processing?

Answer: Bilirubin

Bilirubin is photosensitive and degrades rapidly when exposed to light; specimens must be wrapped in foil or placed in an amber container.

What is the purpose of a separator gel in SST or PST tubes?

Answer: To act as a physical barrier between cells and serum/plasma after centrifugation

The separator gel migrates during centrifugation to form a stable barrier between the cellular components and the serum or plasma, facilitating clean separation.

When must a phlebotomist reject a specimen and request a redraw?

Answer: If the specimen is grossly hemolyzed and the test is affected by hemolysis

Grossly hemolyzed specimens interfere with many analytes (e.g., potassium, LDH, AST) and must be rejected and redrawn to ensure accurate results.

For a urine culture specimen, the appropriate container is:

Answer: A sterile urine cup with a tight-fitting lid

Urine cultures require a sterile container to prevent environmental contamination that could produce false-positive growth results.