NURSING
Fluid & Electrolytes
POP Review Exam
Q&A
2024
,1. A patient with chronic heart failure is admitted to the hospital with
signs of fluid overload. The nurse expects to administer which of the
following medications to reduce the excess fluid volume?
a) Furosemide (Lasix)
b) Spironolactone (Aldactone)
c) Hydrochlorothiazide (HydroDIURIL)
d) Mannitol (Osmitrol)
*Answer: a) Furosemide (Lasix)*
Rationale: Furosemide is a loop diuretic that inhibits sodium and water
reabsorption in the ascending loop of Henle, resulting in increased urine
output and decreased fluid volume. Spironolactone is a potassium-sparing
diuretic that has a weaker diuretic effect than furosemide and may cause
hyperkalemia. Hydrochlorothiazide is a thiazide diuretic that is less
effective than furosemide in treating fluid overload and may also cause
hypokalemia. Mannitol is an osmotic diuretic that is used to treat cerebral
edema and increased intracranial pressure, not fluid overload.
2. A patient with diabetic ketoacidosis (DKA) has a blood glucose level of
600 mg/dL, a serum bicarbonate level of 10 mEq/L, and a blood pH of
7.25. The nurse anticipates that the patient will receive which of the
following intravenous fluids to correct the acid-base imbalance?
a) 0.9% sodium chloride
b) 0.45% sodium chloride
c) Lactated Ringer's solution
d) 5% dextrose in water
*Answer: b) 0.45% sodium chloride*
Rationale: 0.45% sodium chloride is a hypotonic solution that provides
free water to dilute the high serum glucose and sodium levels, as well as
to replace the fluid losses from osmotic diuresis. It also helps to restore the
intracellular fluid volume and prevent cellular dehydration. Lactated
Ringer's solution is an isotonic solution that contains lactate, which can be
converted to bicarbonate in the liver and increase the serum bicarbonate
level, but it may also worsen the hyperglycemia and fluid overload. 0.9%
sodium chloride is an isotonic solution that does not provide free water or
bicarbonate, and may increase the serum sodium level and fluid volume.
5% dextrose in water is a hypertonic solution that will further increase the
serum glucose level and fluid volume, and may cause cerebral edema.
, 3. A patient with severe burns has a serum sodium level of 150 mEq/L, a
serum potassium level of 6 mEq/L, and a serum calcium level of 7 mg/dL.
The nurse recognizes that these electrolyte imbalances are most likely
caused by which of the following mechanisms?
a) Increased aldosterone secretion
b) Decreased antidiuretic hormone secretion
c) Increased cellular membrane permeability
d) Decreased parathyroid hormone secretion
*Answer: c) Increased cellular membrane permeability*
Rationale: Increased cellular membrane permeability due to tissue damage
from burns allows sodium and calcium to leak out of the cells into the
extracellular fluid, resulting in hypernatremia and hypocalcemia.
Potassium also leaks out of the cells into the extracellular fluid, resulting
in hyperkalemia. Aldosterone secretion is decreased in response to
hyperkalemia, leading to further sodium retention and potassium
excretion. Antidiuretic hormone secretion is increased in response to
hypernatremia, leading to water retention and dilutional hyponatremia.
Parathyroid hormone secretion is increased in response to hypocalcemia,
leading to increased calcium reabsorption from the bones and kidneys.
4. A patient with chronic renal failure is receiving hemodialysis three
times a week. The nurse monitors the patient for signs of disequilibrium
syndrome, which may occur during or after dialysis. Which of the
following are manifestations of this syndrome? (Select all that apply.)
a) Headache
b) Nausea
c) Hypertension
d) Muscle cramps
e) Seizures
*Answer: a) Headache, b) Nausea, c) Hypertension, e) Seizures*
Rationale: Disequilibrium syndrome is a complication of hemodialysis
that occurs when there is a rapid decrease in blood urea nitrogen (BUN)
and other solutes during dialysis, creating an osmotic gradient between the
blood and the brain. This causes fluid to shift into the brain cells, resulting
in cerebral edema and increased intracranial pressure. The manifestations
of this syndrome include headache, nausea, vomiting, restlessness,
confusion, hypertension, tachycardia, and seizures. Muscle cramps are not
Fluid & Electrolytes
POP Review Exam
Q&A
2024
,1. A patient with chronic heart failure is admitted to the hospital with
signs of fluid overload. The nurse expects to administer which of the
following medications to reduce the excess fluid volume?
a) Furosemide (Lasix)
b) Spironolactone (Aldactone)
c) Hydrochlorothiazide (HydroDIURIL)
d) Mannitol (Osmitrol)
*Answer: a) Furosemide (Lasix)*
Rationale: Furosemide is a loop diuretic that inhibits sodium and water
reabsorption in the ascending loop of Henle, resulting in increased urine
output and decreased fluid volume. Spironolactone is a potassium-sparing
diuretic that has a weaker diuretic effect than furosemide and may cause
hyperkalemia. Hydrochlorothiazide is a thiazide diuretic that is less
effective than furosemide in treating fluid overload and may also cause
hypokalemia. Mannitol is an osmotic diuretic that is used to treat cerebral
edema and increased intracranial pressure, not fluid overload.
2. A patient with diabetic ketoacidosis (DKA) has a blood glucose level of
600 mg/dL, a serum bicarbonate level of 10 mEq/L, and a blood pH of
7.25. The nurse anticipates that the patient will receive which of the
following intravenous fluids to correct the acid-base imbalance?
a) 0.9% sodium chloride
b) 0.45% sodium chloride
c) Lactated Ringer's solution
d) 5% dextrose in water
*Answer: b) 0.45% sodium chloride*
Rationale: 0.45% sodium chloride is a hypotonic solution that provides
free water to dilute the high serum glucose and sodium levels, as well as
to replace the fluid losses from osmotic diuresis. It also helps to restore the
intracellular fluid volume and prevent cellular dehydration. Lactated
Ringer's solution is an isotonic solution that contains lactate, which can be
converted to bicarbonate in the liver and increase the serum bicarbonate
level, but it may also worsen the hyperglycemia and fluid overload. 0.9%
sodium chloride is an isotonic solution that does not provide free water or
bicarbonate, and may increase the serum sodium level and fluid volume.
5% dextrose in water is a hypertonic solution that will further increase the
serum glucose level and fluid volume, and may cause cerebral edema.
, 3. A patient with severe burns has a serum sodium level of 150 mEq/L, a
serum potassium level of 6 mEq/L, and a serum calcium level of 7 mg/dL.
The nurse recognizes that these electrolyte imbalances are most likely
caused by which of the following mechanisms?
a) Increased aldosterone secretion
b) Decreased antidiuretic hormone secretion
c) Increased cellular membrane permeability
d) Decreased parathyroid hormone secretion
*Answer: c) Increased cellular membrane permeability*
Rationale: Increased cellular membrane permeability due to tissue damage
from burns allows sodium and calcium to leak out of the cells into the
extracellular fluid, resulting in hypernatremia and hypocalcemia.
Potassium also leaks out of the cells into the extracellular fluid, resulting
in hyperkalemia. Aldosterone secretion is decreased in response to
hyperkalemia, leading to further sodium retention and potassium
excretion. Antidiuretic hormone secretion is increased in response to
hypernatremia, leading to water retention and dilutional hyponatremia.
Parathyroid hormone secretion is increased in response to hypocalcemia,
leading to increased calcium reabsorption from the bones and kidneys.
4. A patient with chronic renal failure is receiving hemodialysis three
times a week. The nurse monitors the patient for signs of disequilibrium
syndrome, which may occur during or after dialysis. Which of the
following are manifestations of this syndrome? (Select all that apply.)
a) Headache
b) Nausea
c) Hypertension
d) Muscle cramps
e) Seizures
*Answer: a) Headache, b) Nausea, c) Hypertension, e) Seizures*
Rationale: Disequilibrium syndrome is a complication of hemodialysis
that occurs when there is a rapid decrease in blood urea nitrogen (BUN)
and other solutes during dialysis, creating an osmotic gradient between the
blood and the brain. This causes fluid to shift into the brain cells, resulting
in cerebral edema and increased intracranial pressure. The manifestations
of this syndrome include headache, nausea, vomiting, restlessness,
confusion, hypertension, tachycardia, and seizures. Muscle cramps are not
