CAMRT Contrast Media and Pharmacology Questions and Answers 3

Question 1

What is the mechanism of contrast-induced nephropathy, and who is at highest risk?

Accepted Answer

Direct tubular toxicity and renal vasoconstriction; patients with renal insufficiency and diabetes

Answer

CIN involves direct tubular cell toxicity and vasoconstriction. Pre-existing renal disease and diabetes are key risk factors.

Question 2

Oesophageal perforation is suspected during a barium swallow. Which contrast should be used?

Accepted Answer

Water-soluble low-osmolality non-ionic contrast

Answer

Low-osmolality non-ionic contrast is safest when perforation is suspected.

Question 3

What is the appropriate action when contrast extravasation is detected during power injection?

Accepted Answer

Stop immediately, elevate the limb, apply cold compress

Answer

Stop the injection, elevate the limb, and apply cold compresses to reduce swelling.

Question 4

What distinguishes ionic from non-ionic iodinated contrast media?

Accepted Answer

Non-ionic agents do not dissociate, resulting in lower osmolality

Answer

Non-ionic agents remain as single molecules in solution, reducing particle count and osmolality.

Question 5

A patient with pheochromocytoma is scheduled for contrast CT. What risk must the technologist know?

Accepted Answer

Potential hypertensive crisis from catecholamine release

Answer

Contrast can trigger catecholamine release from the tumour, causing hypertensive crisis.

CAMRT - Canadian Association of Medical Radiation Technologists Practice Test