Advanced Patient Assessment Practice Exam

What value represents a normal serum potassium level?

1. 98 to 105 mEq/L

2. 3.5 to 5.0 mEq/L

3. 7 to 20 mEq/L

4. 137 to 147 mEq/L

The correct answer is: 3.5 to 5.0 mEq/L

A normal serum potassium level falls within the range of 3.5 to 5.0 mEq/L. Potassium is a critical electrolyte that plays a vital role in various physiological functions, including maintaining cellular homeostasis, regulating heart rhythm, and ensuring proper muscle function. Values within this specified range indicate that the body's potassium levels are balanced, which is essential for proper electrical conduction in the heart and optimal muscle function. Obvious deviations from this range can lead to serious complications. For instance, levels below 3.5 mEq/L (hypokalemia) can cause muscle weakness, cramps, arrhythmias, and can be life-threatening. Conversely, high levels above 5.0 mEq/L (hyperkalemia) can also lead to dangerous cardiac issues, including potential cardiac arrest. The other ranges provided do not correspond to the normal serum potassium level: the other values represent different laboratory measurements or are value ranges for other substances. Knowing the correct value for serum potassium is crucial in both clinical settings and patient assessments to ensure appropriate diagnosis and treatment.