Phlebotomy Test Arterial Blood Gas Collection 3

Question 1

Which of the following is a contraindication to using the brachial artery for ABG collection?

Accepted Answer

There is no collateral circulation to the forearm if the brachial artery is damaged

Answer

The radial Allen test is negative bilaterally

Answer

The patient has a history of elbow surgery

Answer

The brachial artery is too large for ABG collection

Question 2

A patient has a PaO2 of 58 mmHg while breathing room air. This finding indicates:

Accepted Answer

Hypoxemia requiring clinical intervention

Answer

Normal oxygenation for an elderly patient

Answer

Adequate oxygenation—above the critical threshold of 55 mmHg

Answer

The patient needs immediate intubation

Question 3

An ABG shows: pH 7.30, PCO2 55 mmHg, HCO3 26 mEq/L. The phlebotomist correctly identifies this as:

Accepted Answer

Respiratory acidosis (uncompensated)

Answer

Metabolic acidosis with respiratory compensation

Answer

Respiratory alkalosis

Answer

Normal arterial blood gas values

Question 4

The femoral artery is used as an alternative ABG site primarily in which clinical scenario?

Accepted Answer

When radial and brachial sites are inaccessible (e.g., severe peripheral vascular disease, cardiac arrest)

Answer

When the patient is awake and cooperative

Answer

When a larger blood volume is needed

Answer

When the patient has a bleeding disorder

Question 5

How much pressure must be applied to a radial artery puncture site to achieve hemostasis in a patient with normal coagulation?

Accepted Answer

At least 3–5 minutes of continuous firm pressure

Answer

30 seconds of firm pressure

Answer

1–2 minutes of light pressure

Answer

Until a clot is visibly formed at the surface

Question 6

A patient's ABG specimen was left at room temperature for 2 hours before analysis. Which result is MOST likely to be falsely altered?

Accepted Answer

pH falsely decreased, PO2 falsely decreased, PCO2 falsely increased

Answer

pH falsely elevated, PO2 falsely elevated, PCO2 falsely decreased

Answer

No significant changes occur within 2 hours at room temperature

Answer

Only pH changes; PO2 and PCO2 remain stable

Question 7

What does the term 'base excess' (BE) represent in an ABG report?

Accepted Answer

The amount of strong acid or base required to return blood pH to normal at standard conditions

Answer

The amount of oxygen bound to hemoglobin above normal

Answer

The excess bicarbonate above the normal 22–26 mEq/L range

Answer

The difference between arterial and venous pH

Question 8

After ABG collection, the phlebotomist must label the syringe with which of the following patient information immediately at the bedside?

Accepted Answer

Patient name, date of birth (or ID number), date and time of collection, and FiO2 or oxygen delivery information

Answer

Only the patient's name and date of birth

Answer

Room number and collection time only

Answer

The phlebotomist's name only—the nurse documents the rest