Phlebotomy Test Capillary and Dermal Puncture 2

Question 1

Which lancet depth is recommended for an adult fingerstick to ensure adequate blood collection without causing undue pain?

Accepted Answer

1.5–2.0 mm

Answer

0.5–1.0 mm

Answer

2.4–3.0 mm

Answer

3.5–4.0 mm

Question 2

A capillary blood glucose result is typically considered to be which of the following compared to a venous plasma glucose?

Accepted Answer

Approximately equal to or slightly higher than venous plasma glucose

Answer

10–15% lower than venous plasma glucose

Answer

Always 20% higher due to arterial mixing

Answer

Identical—there is no difference

Question 3

Which of the following is an absolute contraindication for a fingerstick on a specific finger?

Accepted Answer

Fingers with edema or poor circulation

Answer

Cold fingers

Answer

Fingers with nail polish

Answer

Dominant hand fingers

Question 4

For a neonatal PKU screening (newborn screening), the blood specimen is collected on which type of collection device?

Accepted Answer

Blood spot filter paper card (Guthrie card)

Answer

Micro-collection tube (Microtainer)

Answer

Standard EDTA tube (lavender top)

Answer

Heparinized capillary tube

Question 5

After a fingerstick, the patient should be instructed to hold their finger:

Accepted Answer

Elevated above heart level with pressure applied

Answer

Dependent (hanging down) with gentle pressure applied

Answer

In a fist to promote blood flow

Answer

Submerged in cold water to stop bleeding

Question 6

Which micro-collection tube (Microtainer) color is used for hematology testing (CBC) in capillary collection?

Accepted Answer

Lavender/purple (EDTA)

Answer

Gold (serum separator)

Answer

Green (heparin)

Answer

Light blue (sodium citrate)

Question 7

Why should a capillary blood gas specimen be collected in a heparinized capillary tube and immediately sealed at both ends?

Accepted Answer

To prevent exposure to atmospheric air that would alter CO2 and O2 levels

Answer

To prevent evaporation of the liquid sample

Answer

To keep the specimen at body temperature during transport

Answer

To prevent clotting before analysis

Question 8

A heelstick is performed on a 3-day-old full-term newborn. Which of the following actions is INCORRECT?

Accepted Answer

Puncturing the posterior curve (back) of the heel

Answer

Warming the heel for 3–5 minutes before puncture

Answer

Using a blade depth no greater than 2.0 mm

Answer

Collecting the specimen in the medial plantar area