CIR Contrast Media Administration & Adverse Reaction Management 3

Question 1

According to ACR guidelines, at what eGFR threshold is the risk of contrast-induced acute kidney injury MOST significantly elevated?

Accepted Answer

eGFR < 30 mL/min/1.73m²

Answer

The ACR identifies eGFR < 30 mL/min/1.73m² as the threshold of highest risk for contrast-induced acute kidney injury, warranting careful risk-benefit analysis before contrast use.

Question 2

How long should metformin be withheld AFTER contrast administration in a patient with renal impairment (eGFR < 45)?

Accepted Answer

48 hours

Answer

Metformin must be held for 48 hours after contrast in renally impaired patients to prevent lactic acidosis, which can develop if CIN further reduces metformin clearance.

Question 3

The Laskey formula for estimating safe contrast volume in renally impaired patients uses which ratio?

Accepted Answer

Contrast volume ÷ eGFR (should be < 3.7)

Answer

The Laskey formula defines contrast volume (mL) divided by eGFR (mL/min/1.73m²); a ratio below 3.7 is associated with lower CIN risk in patients with renal impairment.

Question 4

A pregnant patient requires emergency coronary angiography. What is the PRIMARY contrast-related concern for the neonate?

Accepted Answer

Transient neonatal hypothyroidism from iodine exposure

Answer

Iodinated contrast crosses the placenta and free iodine can suppress neonatal thyroid function, making neonatal thyroid function testing recommended after in-utero exposure.

Question 5

Which contrast media property is MOST important for minimizing direct cardiac toxicity during intracoronary injection?

Accepted Answer

Low ionicity and low osmolality

Answer

Low ionicity reduces the direct electrophysiologic effects on myocardium while low osmolality minimizes osmotic stress on red blood cells and endothelium during coronary injections.

CIR - Cardiac Interventional Radiology Practice Test

CIR - Cardiac Interventional Radiology Practice Test

CIR Contrast Media Administration & Adverse Reaction Management 3