100 multiple-choice questions with correct answers and detailed rationales.
Covers potassium, sodium, calcium, magnesium, phosphate, chloride imbalances,
acid-base disorders (metabolic/respiratory acidosis/alkalosis), IV fluid therapy,
diuretic effects, clinical manifestations, nursing interventions, and priority
assessments. Designed for nursing students to reinforce critical thinking,
lab value interpretation, and safe patient care. Updated with latest evidence -based
content. Ideal for exam preparation and remediation.
1. The nurse is caring for a client with hypocalcemia. Which clinical manifestation should the
nurse expect to assess?
a. Positive Trousseau's sign.
b. Decreased deep tendon reflexes.
c. Lethargy and confusion.
d. Constipation.
Correct Answer: a. Positive Trousseau's sign.
Rationale: Hypocalcemia (low serum calcium) increases neuromuscular excitability because
calcium acts as a membrane stabilizer. A positive Trousseau's sign is elicited by inflating a blood
pressure cuff above systolic pressure for 3 minutes; if the client develops carpal spasm (flexion
of the wrist and fingers), it indicates hypocalcemia. Chvostek's sign is another indicator (facial
twitching when tapping the facial nerve). Decreased deep tendon reflexes, lethargy, and
constipation are associated with hypercalcemia. Therefore, Trousseau's sign is a specific
manifestation of hypocalcemia.
[1]
,2. The nurse is assessing a client who has a serum sodium level of 120 mEq/L. Which neurologic
finding would be most concerning?
a. Headache.
b. Nausea.
c. Seizures.
d. Confusion.
Correct Answer: c. Seizures.
Rationale: Hyponatremia (serum sodium < 135 mEq/L) causes water to shift into brain cells,
leading to cerebral edema. As the sodium level drops to 120 mEq/L, neurologic symptoms
worsen. Seizures are a severe and life-threatening complication of hyponatremia because the
cerebral edema increases intracranial pressure and disrupts neuronal electrical activity. While
headache, nausea, and confusion are also symptoms, seizures indicate a critical level of
neurologic impairment requiring immediate intervention. Therefore, seizures are the most
concerning finding.
3. A client with heart failure is prescribed furosemide (Lasix). Which laboratory value should the
nurse monitor most closely?
a. Serum sodium.
b. Serum potassium.
c. Serum calcium.
d. Serum magnesium.
Correct Answer: b. Serum potassium.
Rationale: Furosemide is a loop diuretic that inhibits sodium and chloride reabsorption in the
ascending loop of Henle. It also increases potassium excretion because sodium delivery to the
[2]
,distal tubule is enhanced, promoting sodium-potassium exchange. Hypokalemia is a common
and dangerous side effect, especially in clients with heart failure who may also take digoxin,
because hypokalemia increases the risk of digoxin toxicity. While sodium, calcium, and
magnesium can also be affected, potassium imbalance poses the greatest immediate risk. Thus,
serum potassium should be monitored most closely.
4. The nurse is caring for assigned clients. The nurse should see the client with which of the
following symptoms first?
a. Serum potassium concentration is decreasing; abdominal distention, but denies any
difficulty breathing.
b. Serum calcium concentration is increasing; reports constipation; is alert and denies any
discomfort.
c. Serum potassium concentration is increasing; has developed cardiac dysrhythmias, but
denies any difficulty breathing.
d. Serum calcium concentration is decreasing; reports constipation; is alert and reports a pain
level of 3 on a scale of 0 (no pain) to 10 (severe pain).
Correct Answer: c. Serum potassium concentration is increasing; has developed cardiac
dysrhythmias, but denies any difficulty breathing.
Rationale: Hyperkalemia (increasing serum potassium) is a life-threatening electrolyte
imbalance because it can cause fatal cardiac dysrhythmias, including ventricular fibrillation and
asystole. The presence of cardiac dysrhythmias indicates that the hyperkalemia is already
affecting the heart, requiring immediate intervention regardless of the absence of respiratory
distress. Hypokalemia with abdominal distention (option a) is concerning but less immediately
life-threatening. Hypercalcemia with constipation (option b) and hypocalcemia with
constipation and mild pain (option d) are serious but do not carry the same immediate risk of
sudden cardiac death. Thus, the client with hyperkalemia and cardiac dysrhythmias must be
seen first.
5. The nurse is caring for the following clients. The nurse identifies which client as being at risk
for developing metabolic acidosis?
[3]
, a. The client who is extremely anxious.
b. The client who has had diarrhea for over a week.
c. The client who has a nasogastric (NG) tube.
d. The client who has newly diagnosed pneumonia.
Correct Answer: b. The client who has had diarrhea for over a week.
Rationale: Prolonged diarrhea leads to excessive loss of bicarbonate-rich intestinal fluid,
resulting in metabolic acidosis. The normal GI tract secretes and reabsorbs bicarbonate; when
diarrhea occurs, this bicarbonate is lost, causing a decrease in serum pH. Extreme anxiety leads
to respiratory alkalosis due to hyperventilation, not metabolic acidosis. NG tube suctioning
removes gastric acid (HCl), leading to metabolic alkalosis, not acidosis. Pneumonia can cause
respiratory acidosis due to impaired gas exchange and CO2 retention, but it is a respiratory, not
metabolic, acid-base disturbance. Therefore, the client with prolonged diarrhea is at risk for
metabolic acidosis.
6. The nurse is assessing a client with severe vomiting for 3 days. Which acid-base imbalance is
this client most at risk for developing?
a. Metabolic acidosis.
b. Metabolic alkalosis.
c. Respiratory acidosis.
d. Respiratory alkalosis.
Correct Answer: b. Metabolic alkalosis.
Rationale: Severe vomiting leads to the loss of gastric hydrochloric acid (HCl). The stomach
normally secretes HCl, which contains hydrogen ions (H+). When these are lost, the serum
bicarbonate level increases relative to acid, causing metabolic alkalosis. This is characterized by
an elevated pH and elevated bicarbonate. Metabolic acidosis would occur with diarrhea or
renal failure. Respiratory acidosis and alkalosis are related to lung function and CO2 retention
[4]
Covers potassium, sodium, calcium, magnesium, phosphate, chloride imbalances,
acid-base disorders (metabolic/respiratory acidosis/alkalosis), IV fluid therapy,
diuretic effects, clinical manifestations, nursing interventions, and priority
assessments. Designed for nursing students to reinforce critical thinking,
lab value interpretation, and safe patient care. Updated with latest evidence -based
content. Ideal for exam preparation and remediation.
1. The nurse is caring for a client with hypocalcemia. Which clinical manifestation should the
nurse expect to assess?
a. Positive Trousseau's sign.
b. Decreased deep tendon reflexes.
c. Lethargy and confusion.
d. Constipation.
Correct Answer: a. Positive Trousseau's sign.
Rationale: Hypocalcemia (low serum calcium) increases neuromuscular excitability because
calcium acts as a membrane stabilizer. A positive Trousseau's sign is elicited by inflating a blood
pressure cuff above systolic pressure for 3 minutes; if the client develops carpal spasm (flexion
of the wrist and fingers), it indicates hypocalcemia. Chvostek's sign is another indicator (facial
twitching when tapping the facial nerve). Decreased deep tendon reflexes, lethargy, and
constipation are associated with hypercalcemia. Therefore, Trousseau's sign is a specific
manifestation of hypocalcemia.
[1]
,2. The nurse is assessing a client who has a serum sodium level of 120 mEq/L. Which neurologic
finding would be most concerning?
a. Headache.
b. Nausea.
c. Seizures.
d. Confusion.
Correct Answer: c. Seizures.
Rationale: Hyponatremia (serum sodium < 135 mEq/L) causes water to shift into brain cells,
leading to cerebral edema. As the sodium level drops to 120 mEq/L, neurologic symptoms
worsen. Seizures are a severe and life-threatening complication of hyponatremia because the
cerebral edema increases intracranial pressure and disrupts neuronal electrical activity. While
headache, nausea, and confusion are also symptoms, seizures indicate a critical level of
neurologic impairment requiring immediate intervention. Therefore, seizures are the most
concerning finding.
3. A client with heart failure is prescribed furosemide (Lasix). Which laboratory value should the
nurse monitor most closely?
a. Serum sodium.
b. Serum potassium.
c. Serum calcium.
d. Serum magnesium.
Correct Answer: b. Serum potassium.
Rationale: Furosemide is a loop diuretic that inhibits sodium and chloride reabsorption in the
ascending loop of Henle. It also increases potassium excretion because sodium delivery to the
[2]
,distal tubule is enhanced, promoting sodium-potassium exchange. Hypokalemia is a common
and dangerous side effect, especially in clients with heart failure who may also take digoxin,
because hypokalemia increases the risk of digoxin toxicity. While sodium, calcium, and
magnesium can also be affected, potassium imbalance poses the greatest immediate risk. Thus,
serum potassium should be monitored most closely.
4. The nurse is caring for assigned clients. The nurse should see the client with which of the
following symptoms first?
a. Serum potassium concentration is decreasing; abdominal distention, but denies any
difficulty breathing.
b. Serum calcium concentration is increasing; reports constipation; is alert and denies any
discomfort.
c. Serum potassium concentration is increasing; has developed cardiac dysrhythmias, but
denies any difficulty breathing.
d. Serum calcium concentration is decreasing; reports constipation; is alert and reports a pain
level of 3 on a scale of 0 (no pain) to 10 (severe pain).
Correct Answer: c. Serum potassium concentration is increasing; has developed cardiac
dysrhythmias, but denies any difficulty breathing.
Rationale: Hyperkalemia (increasing serum potassium) is a life-threatening electrolyte
imbalance because it can cause fatal cardiac dysrhythmias, including ventricular fibrillation and
asystole. The presence of cardiac dysrhythmias indicates that the hyperkalemia is already
affecting the heart, requiring immediate intervention regardless of the absence of respiratory
distress. Hypokalemia with abdominal distention (option a) is concerning but less immediately
life-threatening. Hypercalcemia with constipation (option b) and hypocalcemia with
constipation and mild pain (option d) are serious but do not carry the same immediate risk of
sudden cardiac death. Thus, the client with hyperkalemia and cardiac dysrhythmias must be
seen first.
5. The nurse is caring for the following clients. The nurse identifies which client as being at risk
for developing metabolic acidosis?
[3]
, a. The client who is extremely anxious.
b. The client who has had diarrhea for over a week.
c. The client who has a nasogastric (NG) tube.
d. The client who has newly diagnosed pneumonia.
Correct Answer: b. The client who has had diarrhea for over a week.
Rationale: Prolonged diarrhea leads to excessive loss of bicarbonate-rich intestinal fluid,
resulting in metabolic acidosis. The normal GI tract secretes and reabsorbs bicarbonate; when
diarrhea occurs, this bicarbonate is lost, causing a decrease in serum pH. Extreme anxiety leads
to respiratory alkalosis due to hyperventilation, not metabolic acidosis. NG tube suctioning
removes gastric acid (HCl), leading to metabolic alkalosis, not acidosis. Pneumonia can cause
respiratory acidosis due to impaired gas exchange and CO2 retention, but it is a respiratory, not
metabolic, acid-base disturbance. Therefore, the client with prolonged diarrhea is at risk for
metabolic acidosis.
6. The nurse is assessing a client with severe vomiting for 3 days. Which acid-base imbalance is
this client most at risk for developing?
a. Metabolic acidosis.
b. Metabolic alkalosis.
c. Respiratory acidosis.
d. Respiratory alkalosis.
Correct Answer: b. Metabolic alkalosis.
Rationale: Severe vomiting leads to the loss of gastric hydrochloric acid (HCl). The stomach
normally secretes HCl, which contains hydrogen ions (H+). When these are lost, the serum
bicarbonate level increases relative to acid, causing metabolic alkalosis. This is characterized by
an elevated pH and elevated bicarbonate. Metabolic acidosis would occur with diarrhea or
renal failure. Respiratory acidosis and alkalosis are related to lung function and CO2 retention
[4]
