Adult Critical Care Specialty (ACCS) Practice Exam

In a patient experiencing renal failure, which laboratory value would likely be highest?

1. Glucose

2. Potassium

3. Sodium

4. Albumin

The correct answer is: Potassium

In the context of a patient experiencing renal failure, elevated potassium levels are a common and significant laboratory finding. The kidneys play a crucial role in regulating potassium balance in the body by excreting excess potassium. When renal function declines, as seen in renal failure, the kidney's ability to eliminate potassium diminishes, leading to hyperkalemia, which is an elevated concentration of potassium in the blood. Hyperkalemia can have serious consequences, including cardiac arrhythmias and muscle weakness, making it a critical parameter to monitor in patients with renal failure. This is why potassium is likely the highest laboratory value in these patients compared to glucose, sodium, or albumin. Glucose levels might be affected in various ways, such as due to stress, but they are not directly influenced by renal clearance to the same extent as potassium. Sodium levels can also fluctuate but are typically more regulated in comparison. Albumin levels can decrease with kidney disease but tend to be lower overall rather than significantly elevated. Consequently, elevated potassium is a hallmark of renal failure, making it the most pertinent choice in this case.