KNOWLEDGE DRILL 10-3: TRUE OR FALSE ACTIVITY All false. Circle the one or two words that make the statement false and write the correct word/s that would make the statement true in the space provided. 1. Microtubes are often referred to as "bullets" because of their size and shape. 2. Warming the capillary puncture site can increase blood flow up to 10 times. 3. Capillary puncture is sometimes recommended when available veins are fragile or must be saved for other procedures such as a glucose tolerance test. 4. Except for POCT methods, blood specimens for glucose tests cannot be collected by capillary puncture. 5. Microtubes for Chemistry specimens are collected first in the order of draw for capillary puncture. 6. The CLSI recommended site for capillary puncture on adults and children older than 1 year is the palmar surface of the ring finger of the dominant hand. 7. The safest area for heel puncture during transportation and handling is the medial or lateral plantar surface of the heel. 8. Neonatal bilirubin specimens must be kept cool during transportation and handling. 9. Phenylketonuria is a temporarily acquired disorder. 10. Blood spot circles for newborn screening tests are filled by applying a large drop of free-flowing blood to each side of the filter paper.
The Correct Answer and Explanation is:
Here are the corrected TRUE statements and explanations for each of the originally FALSE statements in Knowledge Drill 10-3:
- False word(s): None — this statement is TRUE.
Correct version: Microtubes are often referred to as “bullets” because of their size and shape. - False word(s): 10 times
Correct word(s): seven times
Correct version: Warming the capillary puncture site can increase blood flow up to seven times. - False word(s): glucose tolerance test
Correct word(s): chemotherapy or other venipuncture-requiring procedures
Correct version: Capillary puncture is sometimes recommended when available veins are fragile or must be saved for other procedures such as chemotherapy. - False word(s): cannot be
Correct word(s): can be
Correct version: Except for POCT methods, blood specimens for glucose tests can be collected by capillary puncture. - False word(s): Chemistry specimens
Correct word(s): Blood gas specimens
Correct version: Microtubes for blood gas specimens are collected first in the order of draw for capillary puncture. - False word(s): dominant hand
Correct word(s): nondominant hand
Correct version: The CLSI recommended site for capillary puncture on adults and children older than 1 year is the palmar surface of the ring finger of the nondominant hand. - False word(s): transportation and handling
Correct word(s): capillary puncture
Correct version: The safest area for heel puncture during capillary puncture is the medial or lateral plantar surface of the heel. - False word(s): kept cool
Correct word(s): protected from light
Correct version: Neonatal bilirubin specimens must be protected from light during transportation and handling. - False word(s): temporarily acquired
Correct word(s): inherited genetic
Correct version: Phenylketonuria is an inherited genetic disorder. - False word(s): each side
Correct word(s): one side
Correct version: Blood spot circles for newborn screening tests are filled by applying a large drop of free-flowing blood to one side of the filter paper.
Explanation
Capillary blood collection is vital in pediatric and special care patients when venipuncture is impractical. Each statement in this drill highlights common misconceptions. For instance, microtubes are indeed nicknamed bullets due to their shape. Warming the site improves microcirculation, though only up to seven times, not ten. Capillary puncture is often preferred when venous access is limited or preserved for more invasive procedures like chemotherapy rather than tests like glucose tolerance, which actually require venous samples.
Contrary to belief, glucose testing (besides POCT) can be done with capillary blood, especially in home care or fingerstick settings. The order of draw in capillary punctures differs from venous—blood gases are collected first, not chemistry specimens, to preserve analyte integrity.
The CLSI (Clinical and Laboratory Standards Institute) recommends using the nondominant hand’s ring or middle finger for capillary collection, to reduce discomfort. Heel sticks, commonly used in infants, should target the medial or lateral plantar surfaces to avoid nerve or bone damage—not referencing transportation safety.
Specimens like bilirubin must be shielded from light to prevent breakdown, not cooled. PKU (Phenylketonuria) is not temporary; it’s a genetic metabolic disorder that, if untreated, leads to intellectual disability. Finally, neonatal screening cards must be filled on one side only to ensure proper saturation and prevent inaccurate test results.
Understanding these distinctions ensures accurate specimen collection, test reliability, and patient safety.
