Q.1 Which electrolyte is primarily responsible for maintaining extracellular fluid volume?
Potassium
Sodium
Calcium
Magnesium
Explanation - Sodium is the major cation in extracellular fluid and plays a key role in regulating water balance and extracellular fluid volume.
Correct answer is: Sodium
Q.2 A patient with prolonged vomiting is most at risk for which acid-base imbalance?
Respiratory acidosis
Metabolic acidosis
Respiratory alkalosis
Metabolic alkalosis
Explanation - Loss of gastric acid through vomiting leads to an increase in bicarbonate relative to hydrogen ions, resulting in metabolic alkalosis.
Correct answer is: Metabolic alkalosis
Q.3 Which laboratory value indicates hyperkalemia?
K+ 3.0 mEq/L
K+ 4.5 mEq/L
K+ 5.8 mEq/L
K+ 2.8 mEq/L
Explanation - Normal potassium levels are 3.5–5.0 mEq/L. Levels above 5.0 mEq/L indicate hyperkalemia.
Correct answer is: K+ 5.8 mEq/L
Q.4 Which fluid is considered isotonic?
0.45% NaCl
0.9% NaCl
D5W
3% NaCl
Explanation - 0.9% sodium chloride has the same osmolarity as plasma and is therefore isotonic, used for fluid replacement.
Correct answer is: 0.9% NaCl
Q.5 A patient with dehydration is likely to have which of the following vital sign changes?
Bradycardia
Hypotension
Tachypnea
Low temperature
Explanation - Dehydration leads to decreased circulating volume, resulting in hypotension. Tachycardia is also common as a compensatory mechanism.
Correct answer is: Hypotension
Q.6 Which electrolyte imbalance is most commonly associated with tetany?
Hypokalemia
Hypernatremia
Hypocalcemia
Hypermagnesemia
Explanation - Low calcium levels increase neuromuscular excitability, leading to tetany (muscle spasms).
Correct answer is: Hypocalcemia
Q.7 Which clinical sign is indicative of fluid overload?
Dry mucous membranes
Peripheral edema
Weight loss
Hypotension
Explanation - Excess fluid in the extracellular space often manifests as peripheral edema, along with weight gain and hypertension.
Correct answer is: Peripheral edema
Q.8 Which acid-base imbalance is commonly seen in uncontrolled diabetes mellitus?
Metabolic acidosis
Respiratory alkalosis
Metabolic alkalosis
Respiratory acidosis
Explanation - Diabetic ketoacidosis causes accumulation of ketone bodies, which are acidic, leading to metabolic acidosis.
Correct answer is: Metabolic acidosis
Q.9 A patient receiving loop diuretics is at risk for which electrolyte imbalance?
Hyperkalemia
Hypokalemia
Hypercalcemia
Hypernatremia
Explanation - Loop diuretics increase renal potassium excretion, leading to hypokalemia.
Correct answer is: Hypokalemia
Q.10 Which of the following is a symptom of hyponatremia?
Polyuria
Confusion
Muscle cramps
Constipation
Explanation - Low sodium levels affect neural function, leading to confusion, lethargy, and possibly seizures.
Correct answer is: Confusion
Q.11 Which fluid is most appropriate for rapid volume replacement in hypovolemic shock?
0.45% NaCl
5% Dextrose in water
0.9% NaCl
10% Dextrose in water
Explanation - Isotonic saline quickly restores intravascular volume without causing fluid shifts.
Correct answer is: 0.9% NaCl
Q.12 Which electrolyte is essential for cardiac muscle contraction and nerve conduction?
Sodium
Potassium
Magnesium
All of the above
Explanation - Sodium, potassium, and magnesium are all critical for cardiac and nerve function.
Correct answer is: All of the above
Q.13 Which laboratory test is most reliable for assessing a patient’s acid-base status?
Serum potassium
Arterial blood gas (ABG)
Serum calcium
Urine pH
Explanation - ABG analysis provides accurate measurement of pH, CO2, and bicarbonate, reflecting acid-base status.
Correct answer is: Arterial blood gas (ABG)
Q.14 A patient with hyperventilation is most likely experiencing which acid-base imbalance?
Metabolic acidosis
Respiratory alkalosis
Metabolic alkalosis
Respiratory acidosis
Explanation - Excessive exhalation of CO2 decreases hydrogen ion concentration, causing respiratory alkalosis.
Correct answer is: Respiratory alkalosis
Q.15 Which is a common cause of hypomagnesemia?
Chronic alcoholism
Excessive antacid use
Hyperparathyroidism
Hyperkalemia
Explanation - Alcohol increases magnesium excretion and decreases intake, causing hypomagnesemia.
Correct answer is: Chronic alcoholism
Q.16 Which electrolyte imbalance may cause peaked T waves on an ECG?
Hypokalemia
Hyperkalemia
Hypocalcemia
Hypernatremia
Explanation - Elevated potassium levels alter cardiac conduction, producing characteristic ECG changes such as peaked T waves.
Correct answer is: Hyperkalemia
Q.17 Which fluid shift occurs in hypernatremia?
Water moves into cells
Water moves out of cells
No fluid shift
Depends on potassium levels
Explanation - High extracellular sodium draws water out of cells, leading to cellular dehydration.
Correct answer is: Water moves out of cells
Q.18 A patient with renal failure is at risk for which electrolyte imbalance?
Hyperkalemia
Hypokalemia
Hypercalcemia
Hyponatremia
Explanation - Impaired renal excretion of potassium causes hyperkalemia in patients with renal failure.
Correct answer is: Hyperkalemia
Q.19 Which condition is associated with low bicarbonate levels?
Metabolic acidosis
Metabolic alkalosis
Respiratory acidosis
Respiratory alkalosis
Explanation - Low bicarbonate reflects loss of base or accumulation of acid, typical in metabolic acidosis.
Correct answer is: Metabolic acidosis
Q.20 Which electrolyte is primarily regulated by the parathyroid hormone?
Sodium
Potassium
Calcium
Chloride
Explanation - Parathyroid hormone increases blood calcium by stimulating bone resorption and enhancing renal reabsorption.
Correct answer is: Calcium
Q.21 Which symptom is commonly seen in hypokalemia?
Muscle weakness
Bradycardia
Confusion
Twitching
Explanation - Low potassium levels impair neuromuscular function, leading to muscle weakness and cramps.
Correct answer is: Muscle weakness
Q.22 Which intervention is most appropriate for a patient with hypernatremia?
Restrict fluids
Administer hypotonic fluids
Administer isotonic fluids
Increase sodium intake
Explanation - Hypotonic fluids help move water into cells, correcting the hypernatremia safely.
Correct answer is: Administer hypotonic fluids
Q.23 Which electrolyte imbalance can cause Chvostek’s sign?
Hypocalcemia
Hypercalcemia
Hypernatremia
Hypokalemia
Explanation - Tapping the facial nerve elicits facial muscle twitching in hypocalcemia, known as Chvostek’s sign.
Correct answer is: Hypocalcemia
Q.24 Which acid-base disturbance is most likely in a patient with chronic obstructive pulmonary disease (COPD)?
Respiratory acidosis
Respiratory alkalosis
Metabolic acidosis
Metabolic alkalosis
Explanation - COPD causes impaired CO2 excretion, leading to CO2 retention and respiratory acidosis.
Correct answer is: Respiratory acidosis
Q.25 Which sign is associated with fluid deficit?
Jugular vein distension
Tenting of the skin
Peripheral edema
Bounding pulse
Explanation - Loss of skin elasticity (tenting) is a classic sign of dehydration and fluid deficit.
Correct answer is: Tenting of the skin