STUVIA 2024/2025
Ch 12: Fluid Volume and Electrolytes
Ch 12: Fluid Volume and Electrolytes
ANS: C
Rationale: Normal osmolality is 275 to 295 mOsm/kg. This patient is therefore hyper-osmolar. - ✔✔A
patient's serum osmolality is 305 mOsm/kg. Which term describes this patient's body fluid osmolality?
a. Iso-osmolar
b. Hypo-osmolar
c. Hyper-osmolar
d. Isotonic
ANS: D
Rationale: Lactated Ringer's solution is an isotonic solution and is used to replace water and
electrolytes and is often used to replace gastrointestinal losses. Hypotonic fluids increase interstitial
and intracellular hydration. Colloidal solutions are used to maintain plasma volume over time.
Hypertonic solutions pull water from the interstitial space into the extracellular fluid. - ✔✔A patient is
admitted after experiencing vomiting and diarrhea for several days. The provider orders intravenous
%
lactated Ringer's solution. The nurse understands that this fluid is given for which purpose?
a. To increase interstitial and intracellular hydration
b. To maintain plasma volume over time
c. To pull water from the interstitial space into the extracellular fluid
d. To replace water and electrolytes
ANS: D
Rationale: 6% Dextran 75 is a high-molecular-weight colloidal solution and is used to treat shock from
hemorrhage, burns, or trauma. Colloids are plasma expanders, and the end result is an improvement
in heart rate (decreased) and blood pressure (increased). Plasma expanders will result in an increase
in urine output. Blood oxygenation is not affected, and colloids do not increase the amount of
interstitial fluid. - ✔✔A patient is being treated for shock after a motor vehicle accident. The provider
orders 6% dextran 75 to be given intravenously. The nurse should expect which outcome as the
result of this infusion?
a. Decreased urine output
b. Improved blood oxygenation
c. Increased interstitial fluid
d. Stabilization of heart rate and blood pressure
stuvia
, STUVIA 2024/2025
ANS: A
Rationale: The recommended daily fluid intake for adults is 30 to 40 mL/kg/day. This patient should
have a minimum of 2250 mL/day and is currently receiving 1200 mL IV plus 100 mL orally
for a total of 1300 mL. Increasing the IV rate to 90 mL/h would give the patient 2160 mL. If
the patient continues to take oral fluids, the amount of 2250 mL can be met. A rate of 150
mL/h would give the patient 3600 mL/day, which exceeds the recommended amount. Since
this patient is not taking fluids well and is not receiving adequate IV fluids, encouraging an
increased fluid intake is not indicated. Even if the patient drank 250 mL of water every 8
hours, the amount would not be sufficient. - ✔✔The nurse is caring for a patient who weighs 75 kg.
The patient has intravenous (IV) fluids infusing at a rate of 50 mL/h and has consumed 100 mL of
fluids orally in the past 24 hours. Which action will the nurse take?
a. Contact the provider to ask about increasing the IV rate to 90 mL/h.
b. Discuss with the provider the need to increase the IV rate to 150 mL/h.
c. Encourage the patient to drink more water so the IV can be discontinued.
d. Instruct the patient to drink 250 mL of water every 8 hours.
ANS: A
%
Rationale: Patients who are hyponatremic will have tachycardia and hypotension along with lethargy
and muscle weakness. The normal range for serum sodium is 135 to 145 mEq/L; a serum sodium
level of 126 mEq/L would be considered hyponatremic. - ✔✔The nurse is caring for a patient who
has a heart rate of 98 beats per minute and a blood pressure of 82/58 mm Hg. The patient is
lethargic, is complaining of muscle weakness, and has had gastroenteritis for several days. Based on
this patient's vital signs, which sodium value would the nurse expect?
a. 126 mEq/L
b. 140 mEq/L
c. 145 mEq/L
d. 158 mEq/L
ANS: C
Rationale: Patients with hyponatremia may be treated with oral sodium supplements if the patient is
able or if the deficit is mild. This patient is vomiting and would not be able to take supplements easily.
For a serum sodium level between 125 and 135 mEq/L, normal saline may increase sodium content
in vascular fluid. Hypertonic saline is used for severe hyponatremia with a serum sodium <120
mEq/L. Diuretics would further deplete sodium and fluid volume in a patient already likely to be
dehydrated from severe vomiting. - ✔✔The nurse is caring for a patient who has had severe
stuvia
Ch 12: Fluid Volume and Electrolytes
Ch 12: Fluid Volume and Electrolytes
ANS: C
Rationale: Normal osmolality is 275 to 295 mOsm/kg. This patient is therefore hyper-osmolar. - ✔✔A
patient's serum osmolality is 305 mOsm/kg. Which term describes this patient's body fluid osmolality?
a. Iso-osmolar
b. Hypo-osmolar
c. Hyper-osmolar
d. Isotonic
ANS: D
Rationale: Lactated Ringer's solution is an isotonic solution and is used to replace water and
electrolytes and is often used to replace gastrointestinal losses. Hypotonic fluids increase interstitial
and intracellular hydration. Colloidal solutions are used to maintain plasma volume over time.
Hypertonic solutions pull water from the interstitial space into the extracellular fluid. - ✔✔A patient is
admitted after experiencing vomiting and diarrhea for several days. The provider orders intravenous
%
lactated Ringer's solution. The nurse understands that this fluid is given for which purpose?
a. To increase interstitial and intracellular hydration
b. To maintain plasma volume over time
c. To pull water from the interstitial space into the extracellular fluid
d. To replace water and electrolytes
ANS: D
Rationale: 6% Dextran 75 is a high-molecular-weight colloidal solution and is used to treat shock from
hemorrhage, burns, or trauma. Colloids are plasma expanders, and the end result is an improvement
in heart rate (decreased) and blood pressure (increased). Plasma expanders will result in an increase
in urine output. Blood oxygenation is not affected, and colloids do not increase the amount of
interstitial fluid. - ✔✔A patient is being treated for shock after a motor vehicle accident. The provider
orders 6% dextran 75 to be given intravenously. The nurse should expect which outcome as the
result of this infusion?
a. Decreased urine output
b. Improved blood oxygenation
c. Increased interstitial fluid
d. Stabilization of heart rate and blood pressure
stuvia
, STUVIA 2024/2025
ANS: A
Rationale: The recommended daily fluid intake for adults is 30 to 40 mL/kg/day. This patient should
have a minimum of 2250 mL/day and is currently receiving 1200 mL IV plus 100 mL orally
for a total of 1300 mL. Increasing the IV rate to 90 mL/h would give the patient 2160 mL. If
the patient continues to take oral fluids, the amount of 2250 mL can be met. A rate of 150
mL/h would give the patient 3600 mL/day, which exceeds the recommended amount. Since
this patient is not taking fluids well and is not receiving adequate IV fluids, encouraging an
increased fluid intake is not indicated. Even if the patient drank 250 mL of water every 8
hours, the amount would not be sufficient. - ✔✔The nurse is caring for a patient who weighs 75 kg.
The patient has intravenous (IV) fluids infusing at a rate of 50 mL/h and has consumed 100 mL of
fluids orally in the past 24 hours. Which action will the nurse take?
a. Contact the provider to ask about increasing the IV rate to 90 mL/h.
b. Discuss with the provider the need to increase the IV rate to 150 mL/h.
c. Encourage the patient to drink more water so the IV can be discontinued.
d. Instruct the patient to drink 250 mL of water every 8 hours.
ANS: A
%
Rationale: Patients who are hyponatremic will have tachycardia and hypotension along with lethargy
and muscle weakness. The normal range for serum sodium is 135 to 145 mEq/L; a serum sodium
level of 126 mEq/L would be considered hyponatremic. - ✔✔The nurse is caring for a patient who
has a heart rate of 98 beats per minute and a blood pressure of 82/58 mm Hg. The patient is
lethargic, is complaining of muscle weakness, and has had gastroenteritis for several days. Based on
this patient's vital signs, which sodium value would the nurse expect?
a. 126 mEq/L
b. 140 mEq/L
c. 145 mEq/L
d. 158 mEq/L
ANS: C
Rationale: Patients with hyponatremia may be treated with oral sodium supplements if the patient is
able or if the deficit is mild. This patient is vomiting and would not be able to take supplements easily.
For a serum sodium level between 125 and 135 mEq/L, normal saline may increase sodium content
in vascular fluid. Hypertonic saline is used for severe hyponatremia with a serum sodium <120
mEq/L. Diuretics would further deplete sodium and fluid volume in a patient already likely to be
dehydrated from severe vomiting. - ✔✔The nurse is caring for a patient who has had severe
stuvia
