Contrast Media and Pharmacology Questions and Answers Flashcards
6 cards from real CAMRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Contrast Media and Pharmacology Questions and Answers flashcards as text
What is the mechanism of contrast-induced nephropathy, and who is at highest risk?
Answer: Direct tubular toxicity and renal vasoconstriction; patients with renal insufficiency and diabetes
CIN involves direct tubular cell toxicity and vasoconstriction. Pre-existing renal disease and diabetes are key risk factors.
Oesophageal perforation is suspected during a barium swallow. Which contrast should be used?
Answer: Water-soluble low-osmolality non-ionic contrast
Low-osmolality non-ionic contrast is safest when perforation is suspected.
What is the appropriate action when contrast extravasation is detected during power injection?
Answer: Stop immediately, elevate the limb, apply cold compress
Stop the injection, elevate the limb, and apply cold compresses to reduce swelling.
What distinguishes ionic from non-ionic iodinated contrast media?
Answer: Non-ionic agents do not dissociate, resulting in lower osmolality
Non-ionic agents remain as single molecules in solution, reducing particle count and osmolality.
A patient with pheochromocytoma is scheduled for contrast CT. What risk must the technologist know?
Answer: Potential hypertensive crisis from catecholamine release
Contrast can trigger catecholamine release from the tumour, causing hypertensive crisis.
What is the current Canadian fasting protocol for elective contrast-enhanced CT?
Answer: No fasting required; adequate hydration encouraged
Current guidelines no longer require routine fasting, as it does not reduce reactions and may worsen dehydration.