Prescribing Safety Assessment (PSA) Practice Exam

What mechanism causes NSAIDs to potentially lead to renal failure?

1. By increasing blood flow to the kidneys

2. By inhibiting renin production

3. By blocking prostaglandins necessary for vasodilation

4. By promoting glomerular filtration

The correct answer is: By blocking prostaglandins necessary for vasodilation

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to have a significant impact on renal function, and the mechanism that primarily contributes to potential renal failure involves their ability to block prostaglandins necessary for vasodilation. Prostaglandins play a crucial role in maintaining adequate blood flow to the kidneys, especially in situations where the kidney's blood supply may be compromised, such as during dehydration or in the presence of other cardiovascular issues. NSAIDs inhibit the cyclooxygenase (COX) enzymes, which are responsible for the synthesis of prostaglandins. When prostaglandin production is reduced, the afferent arterioles (small blood vessels leading into the glomeruli) may constrict, leading to a decrease in renal blood flow and glomerular filtration rate (GFR). This reduction in blood flow can result in acute kidney injury or worsening of chronic kidney disease, eventually leading to renal failure if the underlying issue is not addressed. As for the other choices, they do not accurately reflect the primary mechanism of NSAID-induced renal impairment. Increasing blood flow to the kidneys, inhibiting renin production, or promoting glomerular filtration would not contribute to renal failure in the way that the inhibition of