CMLA Specimen Collection & Processing 2

Question 1

Which type of specimen typically requires transport on ice to preserve analyte integrity?

Accepted Answer

Ammonia, lactic acid, or arterial blood gas specimens

Answer

Routine CBC lavender tube

Answer

Urine dipstick specimens

Answer

Standard coagulation light blue tubes

Question 2

What does hemolysis in a blood sample indicate, and which test result is most critically affected?

Accepted Answer

Rupture of red blood cells; most critically affects potassium levels

Answer

Excess white blood cells; affects WBC count

Answer

Clot formation; affects coagulation studies

Answer

Bacterial contamination; affects blood culture results

Question 3

What is the correct antiseptic used to prepare the skin site before drawing blood cultures?

Accepted Answer

Povidone-iodine or chlorhexidine gluconate scrub followed by 70% alcohol

Answer

70% isopropyl alcohol alone

Answer

Soap and water only

Answer

Benzalkonium chloride wipe

Question 4

What is the proper handling procedure for a urine culture specimen once collected?

Accepted Answer

Refrigerate at 2–8°C and process within 2 hours, or within 24 hours if refrigerated

Answer

Store at room temperature for up to 24 hours

Answer

Freeze the specimen immediately at -20°C

Answer

Add a preservative and store indefinitely

Question 5

How many times should most anticoagulant blood tubes be gently inverted after collection, and why?

Accepted Answer

8–10 times, to thoroughly mix the additive with blood

Answer

1–2 times, to prevent shaking the sample

Answer

20 or more times, to ensure full anticoagulation

Answer

Inversion is unnecessary; tubes mix automatically in the vacutainer holder

Question 6

What additive is found in gray top tubes, and what is it primarily used to test?

Accepted Answer

Sodium fluoride and potassium oxalate; glucose and blood alcohol levels

Answer

Lithium heparin; lipid panels

Answer

EDTA; complete blood count

Answer

Sodium citrate; coagulation studies

Question 7

When collecting a 24-hour urine specimen, what should the patient do with the first morning void on day one?

Accepted Answer

Discard it and note the time, then collect all urine for the next 24 hours

Answer

Collect it as the first specimen in the container

Answer

Save it in a separate container and add it at the end

Answer

Use it to calibrate the collection volume