Progressive Care Nursing Certification (PCCN) Practice Exam

Which condition can cause an elevation in Blood Urea Nitrogen (BUN)?

1. Hydration

2. Hypotension

3. Excess protein intake

4. All of the above

The correct answer is: Hydration

An elevation in Blood Urea Nitrogen (BUN) can be influenced by several factors, including hydration, hypotension, and excess protein intake. Each of these factors can contribute to an increase in BUN levels. When individuals are dehydrated, kidney perfusion can decrease, leading to reduced renal clearance of urea. This causes an accumulation of urea in the bloodstream, resulting in elevated BUN levels. Hypotension also affects kidney function. Reduced blood pressure may lead to poor perfusion of the kidneys, diminishing their ability to filter waste products, including urea, thus raising BUN levels. Excess protein intake can similarly elevate BUN levels. The metabolism of protein produces urea as a byproduct, and an increase in protein consumption leads to increased urea production, which can elevate BUN levels. Given that all the stated conditions can potentially lead to an elevation in BUN, the most comprehensive answer would acknowledge that all options contribute to this effect.