Fluid & Electrolyte Imbalance: 2026
Clinical Nursing Guide (Exam Prep)
Question 1: An elderly patient is admitted with severe dehydration. Which of the following is the
most reliable indicator of the patient’s daily fluid volume status?
A) Measuring skin turgor on the back of the hand.
B) Assessing the color of the patient's urine.
C) Taking daily daily weights at the same time every morning.
D) Monitoring hourly intake and output accurately.
Correct Answer: C
Rationale: While strict I&O is important, daily weight is the single most accurate indicator of fluid
volume status. A 1 kg (2.2 lbs) sudden weight change represents approximately 1 liter of fluid
gained or lost.
Question 2: A patient with heart failure is experiencing fluid volume excess (hypervolemia). The
nurse assesses the patient and expects to find which classic clinical manifestation?
A) Tachycardia and a thready pulse.
B) Jugular venous distention (JVD) and bounding pulses.
C) Decreased central venous pressure (CVP).
D) Orthostatic hypotension.
Correct Answer: B
Rationale: Fluid overload increases intravascular volume, leading to elevated central venous
pressure, which presents visibly as JVD, bounding peripheral pulses, and hypertension.
Question 3: Which specific laboratory value confirms a state of hemoconcentration in a patient
suffering from severe hypovolemia?
A) Elevated Hematocrit and elevated BUN.
B) Decreased Hematocrit and decreased Serum Sodium.
C) Low urine specific gravity.
D) Decreased serum osmolality.
Correct Answer: A
Rationale: In dehydration (hypovolemia), the loss of plasma water causes the remaining blood
cells and solutes to become more concentrated, leading to an elevated Hematocrit and Blood
Urea Nitrogen (BUN).
Question 4: A patient is receiving a loop diuretic (e.g., Furosemide). The nurse must closely
monitor the patient for which severe electrolyte imbalance?
A) Hypernatremia.
B) Hypokalemia.
,C) Hypercalcemia.
D) Hypermagnesemia.
Correct Answer: B
Rationale: Loop diuretics block the reabsorption of sodium, chloride, and potassium in the Loop
of Henle, leading to profound urinary potassium loss and dangerous hypokalemia.
Question 5: A patient's ECG shows tall, peaked T-waves, a prolonged PR interval, and a
widened QRS complex. These changes are highly indicative of:
A) Hypocalcemia.
B) Hyperkalemia.
C) Hypokalemia.
D) Hypernatremia.
Correct Answer: B
Rationale: Hyperkalemia alters the resting membrane potential of the myocardium. Peaked
T-waves are the earliest sign, which can progress to widened QRS complexes and lethal
arrhythmias like V-Fib or Asystole.
Question 6: The physician orders 40 mEq of Potassium Chloride (KCl) IV for a patient with
hypokalemia. What is the most critical safety rule for the nurse administering this medication?
A) Administer it as a rapid IV push.
B) Administer it intramuscularly if no IV access is available.
C) Never give KCl via IV push; it must always be diluted and infused slowly via a pump.
D) Give it as a bolus over 5 minutes.
Correct Answer: C
Rationale: IV Potassium must NEVER be given IV push or as a bolus. Rapid infusion of
potassium causes immediate cardiac arrest. It must be diluted and infused at a maximum rate of
10 mEq/hour for a peripheral line.
Question 7: A patient admitted with a serum sodium level of 120 mEq/L (Severe Hyponatremia)
is at the highest risk for which life-threatening complication?
A) Sudden cardiac arrest.
B) Seizures and cerebral edema.
C) Pathological bone fractures.
D) Paralytic ileus.
Correct Answer: B
Rationale: Sodium plays a critical role in extracellular osmolality. In severe hyponatremia, water
shifts rapidly into the brain cells (which have higher osmolality), causing cerebral edema,
increased ICP, and seizures.
, Question 8: A patient with Syndrome of Inappropriate Antidiuretic Hormone (SIADH) has
dilutional hyponatremia. The nurse anticipates which primary treatment order?
A) Strict fluid restriction.
B) Massive fluid resuscitation with D5W.
C) Administration of Desmopressin (DDAVP).
D) Increased dietary water intake.
Correct Answer: A
Rationale: In SIADH, the body retains excess free water, which dilutes serum sodium. The
primary treatment is restricting free water intake to allow serum sodium levels to concentrate
back to normal.
Question 9: A patient is undergoing a total thyroidectomy. The nurse knows to assess for signs
of hypocalcemia postoperatively because:
A) The thyroid gland produces calcium.
B) Thyroid surgery causes massive blood loss, depleting calcium.
C) The parathyroid glands may be accidentally removed or damaged during the procedure.
D) Anesthesia inhibits calcium absorption.
Correct Answer: C
Rationale: The parathyroid glands regulate calcium. Since they sit on the posterior aspect of the
thyroid gland, they are at high risk for injury during thyroid surgery, leading to acute
hypocalcemia.
Question 10: The nurse tests for Trousseau’s sign in a patient with suspected hypocalcemia by:
A) Tapping the facial nerve just in front of the ear.
B) Inflating a blood pressure cuff above systolic pressure for 3 minutes and observing for carpal
spasm.
C) Striking the patellar tendon.
D) Assessing the patient's pupillary reaction to light.
Correct Answer: B
Rationale: Trousseau's sign (carpal spasm induced by ischemia from a BP cuff) is a highly
specific clinical indicator of latent tetany caused by hypocalcemia.
Question 11: A patient with chronic alcoholism is admitted with tremors, confusion, and
hyperactive deep tendon reflexes. The nurse anticipates the provider will order lab tests to
check for which deficiency?
A) Hypomagnesemia.
B) Hyperkalemia.
C) Hypernatremia.
D) Hypophosphatemia.
Correct Answer: A
Clinical Nursing Guide (Exam Prep)
Question 1: An elderly patient is admitted with severe dehydration. Which of the following is the
most reliable indicator of the patient’s daily fluid volume status?
A) Measuring skin turgor on the back of the hand.
B) Assessing the color of the patient's urine.
C) Taking daily daily weights at the same time every morning.
D) Monitoring hourly intake and output accurately.
Correct Answer: C
Rationale: While strict I&O is important, daily weight is the single most accurate indicator of fluid
volume status. A 1 kg (2.2 lbs) sudden weight change represents approximately 1 liter of fluid
gained or lost.
Question 2: A patient with heart failure is experiencing fluid volume excess (hypervolemia). The
nurse assesses the patient and expects to find which classic clinical manifestation?
A) Tachycardia and a thready pulse.
B) Jugular venous distention (JVD) and bounding pulses.
C) Decreased central venous pressure (CVP).
D) Orthostatic hypotension.
Correct Answer: B
Rationale: Fluid overload increases intravascular volume, leading to elevated central venous
pressure, which presents visibly as JVD, bounding peripheral pulses, and hypertension.
Question 3: Which specific laboratory value confirms a state of hemoconcentration in a patient
suffering from severe hypovolemia?
A) Elevated Hematocrit and elevated BUN.
B) Decreased Hematocrit and decreased Serum Sodium.
C) Low urine specific gravity.
D) Decreased serum osmolality.
Correct Answer: A
Rationale: In dehydration (hypovolemia), the loss of plasma water causes the remaining blood
cells and solutes to become more concentrated, leading to an elevated Hematocrit and Blood
Urea Nitrogen (BUN).
Question 4: A patient is receiving a loop diuretic (e.g., Furosemide). The nurse must closely
monitor the patient for which severe electrolyte imbalance?
A) Hypernatremia.
B) Hypokalemia.
,C) Hypercalcemia.
D) Hypermagnesemia.
Correct Answer: B
Rationale: Loop diuretics block the reabsorption of sodium, chloride, and potassium in the Loop
of Henle, leading to profound urinary potassium loss and dangerous hypokalemia.
Question 5: A patient's ECG shows tall, peaked T-waves, a prolonged PR interval, and a
widened QRS complex. These changes are highly indicative of:
A) Hypocalcemia.
B) Hyperkalemia.
C) Hypokalemia.
D) Hypernatremia.
Correct Answer: B
Rationale: Hyperkalemia alters the resting membrane potential of the myocardium. Peaked
T-waves are the earliest sign, which can progress to widened QRS complexes and lethal
arrhythmias like V-Fib or Asystole.
Question 6: The physician orders 40 mEq of Potassium Chloride (KCl) IV for a patient with
hypokalemia. What is the most critical safety rule for the nurse administering this medication?
A) Administer it as a rapid IV push.
B) Administer it intramuscularly if no IV access is available.
C) Never give KCl via IV push; it must always be diluted and infused slowly via a pump.
D) Give it as a bolus over 5 minutes.
Correct Answer: C
Rationale: IV Potassium must NEVER be given IV push or as a bolus. Rapid infusion of
potassium causes immediate cardiac arrest. It must be diluted and infused at a maximum rate of
10 mEq/hour for a peripheral line.
Question 7: A patient admitted with a serum sodium level of 120 mEq/L (Severe Hyponatremia)
is at the highest risk for which life-threatening complication?
A) Sudden cardiac arrest.
B) Seizures and cerebral edema.
C) Pathological bone fractures.
D) Paralytic ileus.
Correct Answer: B
Rationale: Sodium plays a critical role in extracellular osmolality. In severe hyponatremia, water
shifts rapidly into the brain cells (which have higher osmolality), causing cerebral edema,
increased ICP, and seizures.
, Question 8: A patient with Syndrome of Inappropriate Antidiuretic Hormone (SIADH) has
dilutional hyponatremia. The nurse anticipates which primary treatment order?
A) Strict fluid restriction.
B) Massive fluid resuscitation with D5W.
C) Administration of Desmopressin (DDAVP).
D) Increased dietary water intake.
Correct Answer: A
Rationale: In SIADH, the body retains excess free water, which dilutes serum sodium. The
primary treatment is restricting free water intake to allow serum sodium levels to concentrate
back to normal.
Question 9: A patient is undergoing a total thyroidectomy. The nurse knows to assess for signs
of hypocalcemia postoperatively because:
A) The thyroid gland produces calcium.
B) Thyroid surgery causes massive blood loss, depleting calcium.
C) The parathyroid glands may be accidentally removed or damaged during the procedure.
D) Anesthesia inhibits calcium absorption.
Correct Answer: C
Rationale: The parathyroid glands regulate calcium. Since they sit on the posterior aspect of the
thyroid gland, they are at high risk for injury during thyroid surgery, leading to acute
hypocalcemia.
Question 10: The nurse tests for Trousseau’s sign in a patient with suspected hypocalcemia by:
A) Tapping the facial nerve just in front of the ear.
B) Inflating a blood pressure cuff above systolic pressure for 3 minutes and observing for carpal
spasm.
C) Striking the patellar tendon.
D) Assessing the patient's pupillary reaction to light.
Correct Answer: B
Rationale: Trousseau's sign (carpal spasm induced by ischemia from a BP cuff) is a highly
specific clinical indicator of latent tetany caused by hypocalcemia.
Question 11: A patient with chronic alcoholism is admitted with tremors, confusion, and
hyperactive deep tendon reflexes. The nurse anticipates the provider will order lab tests to
check for which deficiency?
A) Hypomagnesemia.
B) Hyperkalemia.
C) Hypernatremia.
D) Hypophosphatemia.
Correct Answer: A
