Specimen Collection & Handling Flashcards
7 cards from real CMLA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Specimen Collection & Handling flashcards as text
A specimen requires centrifugation to obtain serum. Which tube type must be allowed to clot completely before centrifugation?
Answer: SST/serum separator tube (gold-top)
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.
A patient refuses to have blood drawn. What is the appropriate response?
Answer: Document the refusal, inform the nurse or provider, and do not collect the specimen
Competent patients have the right to refuse procedures; the refusal should be documented and the ordering provider notified so alternative plans can be made.
Which of the following analytes is most affected by prolonged exposure of a blood specimen to light?
Answer: Bilirubin
Bilirubin is photosensitive and degrades rapidly when exposed to light; specimens for bilirubin testing should be protected with amber tubes or foil.
A requisition calls for a 'trough' drug level. When should this specimen be collected?
Answer: Immediately before the next scheduled dose
Trough levels represent the lowest drug concentration in the blood and must be collected immediately before the next scheduled dose.
Which PPE is required at minimum during routine venipuncture per standard precautions?
Answer: Gloves only
Standard precautions require gloves as a minimum for all venipuncture procedures; additional PPE is added if splash or spray risk is anticipated.
Potassium (K+) results are critically high on a sample with no hemolysis noted. The laboratory assistant should first:
Answer: Check the sample for clots and verify proper collection technique before reporting
Before reporting a critical potassium value, verifying the specimen for clots or preanalytical errors ensures accurate results, since hyperkalemia can trigger dangerous clinical interventions.
Which of the following statements is true regarding the use of a butterfly (winged infusion) set for venipuncture?
Answer: A discard tube should be drawn first when collecting coagulation tests to remove air from the tubing
When using a butterfly set for coagulation testing, a discard tube is drawn first to fill the tubing dead space with blood and prevent air from diluting the sodium citrate ratio.