MSNCB Fluid & Electrolyte Balance

Question 1

A patient's serum sodium level is 128 mEq/L. Which condition does this reflect?

Accepted Answer

Hyponatremia

Answer

Hyponatremia is defined as a serum sodium level below 135 mEq/L, making 128 mEq/L a clear indicator of this imbalance.

Question 2

A nurse assesses a patient and finds muscle weakness, fatigue, and ECG changes showing flattened T waves with prominent U waves. Which electrolyte imbalance is most likely?

Accepted Answer

Hypokalemia

Answer

Hypokalemia causes muscle weakness, fatigue, and characteristic ECG changes including flattened T waves and prominent U waves due to altered myocardial repolarization.

Question 3

Which IV solution is classified as isotonic?

Accepted Answer

0.9% NaCl

Answer

0.9% NaCl (normal saline) has an osmolarity of approximately 308 mOsm/L, matching plasma osmolarity and making it isotonic.

Question 4

A patient with heart failure presents with bilateral lung crackles, peripheral edema, and a 4-pound weight gain in 2 days. Which fluid imbalance does this represent?

Accepted Answer

Fluid volume excess

Answer

Bilateral crackles, peripheral edema, and rapid weight gain are hallmark signs of fluid volume excess (hypervolemia) due to sodium and water retention.

Question 5

A patient with prolonged vomiting and nasogastric suction is at greatest risk for which acid-base imbalance?

Accepted Answer

Metabolic alkalosis

Answer

Loss of hydrochloric acid through vomiting or NG suction removes hydrogen ions from the body, resulting in metabolic alkalosis.

(MSNCB) Medical-Surgical Nursing Certification Board Practice Test

(MSNCB) Medical-Surgical Nursing Certification Board Practice Test

MSNCB Fluid & Electrolyte Balance