CMLA Specimen Collection & Handling 5

Question 1

A specimen requires centrifugation to obtain serum. Which tube type must be allowed to clot completely before centrifugation?

Accepted Answer

SST/serum separator tube (gold-top)

Answer

SST tubes contain a clot activator and gel separator; the tube must be allowed to clot completely (usually 30 minutes) before centrifugation to obtain quality serum.

Question 2

A patient refuses to have blood drawn. What is the appropriate response?

Accepted Answer

Document the refusal, inform the nurse or provider, and do not collect the specimen

Answer

Competent patients have the right to refuse procedures; the refusal should be documented and the ordering provider notified so alternative plans can be made.

Question 3

Which of the following analytes is most affected by prolonged exposure of a blood specimen to light?

Accepted Answer

Bilirubin

Answer

Bilirubin is photosensitive and degrades rapidly when exposed to light; specimens for bilirubin testing should be protected with amber tubes or foil.

Question 4

A requisition calls for a 'trough' drug level. When should this specimen be collected?

Accepted Answer

Immediately before the next scheduled dose

Answer

Trough levels represent the lowest drug concentration in the blood and must be collected immediately before the next scheduled dose.

Question 5

Which PPE is required at minimum during routine venipuncture per standard precautions?

Accepted Answer

Gloves only

Answer

Standard precautions require gloves as a minimum for all venipuncture procedures; additional PPE is added if splash or spray risk is anticipated.

(CMLA) Certified Medical Laboratory Assistant Practice Test

(CMLA) Certified Medical Laboratory Assistant Practice Test

CMLA Specimen Collection & Handling 5