Fluid and Electrolyte Nur 112
The nurse is admitting an older adult with decompensated congestive heart failure. The
nursing assessment reveals adventitious lung sounds, dyspnea, and orthopnea. The nurse
should question which doctor's order?
A. Intravenous (IV) 500 mL of 0.9% NaCl at 125 mL/hr
B.Furosemide (Lasix) 20 mg PO now
C. Oxygen via face mask at 8 L/min
D. KCl 20 mEq PO two times per day -
ANS: A
A patient with decompensated heart failure has extracellular fluid volume (ECV) excess. The
IV of 0.9% NaCl is normal saline, which should be questioned because it would expand ECV
and place an additional load on the failing heart. Diuretics such as furosemide are appropriate
to decrease the ECV during heart failure. Increasing the potassium intake with KCl is
appropriate, because furosemide increases potassium excretion. Oxygen administration is
appropriate in this situation of near pulmonary edema from ECV excess.
The nurse assessed four patients at the beginning of the shift. Which finding should the nurse
report immediately to the physician?
A. Swollen ankles in patient with compensated heart failure
B. Positive Chvostek's sign in patient with acute pancreatitis
C. Dry mucous membranes in patient taking a new diuretic
D. Constipation in patient who has advanced breast cancer -
ANS: B
Positive Chvostek's sign indicates increased neuromuscular excitability, which can progress
to dangerous laryngospasm or seizures and thus needs to be reported first. The other
assessment findings are less urgent and need further assessment. Bilateral ankle edema is a
sign of ECV excess, and follow-up is needed, but the situation is not immediately life-
threatening. Dry mucous membranes in a patient taking a diuretic may be associated with
ECV deficit; however, additional assessments of ECV deficit are required before reporting to
the physician. Constipation has many causes, including hypercalcemia and opioid analgesics,
and it needs action, but not as urgently as a positive Chvostek's sign.
The nurse is assessing a patient before hanging an IV solution of 0.9% NaCl with KCl in it.
Which assessment finding should cause the nurse to hold the IV solution and contact the
physician?
a. Weight gain of 2 pounds since last week
b.Dry mucous membranes and skin tenting
c.Urine output 8 mL/hr
d.Blood pressure 98/58 -
ANS: C
Administering IV potassium to a patient who has oliguria is not safe, because potassium
intake faster than potassium output can cause hyperkalemia with dangerous cardiac
dysrhythmias. Dry mucous membranes, skin tenting, and blood pressure 98/58 are consistent
with the need for IV 0.9% NaCl. Weight gain of 2 pounds in a week does not necessarily
indicate fluid overload, because it can be from increased nutritional intake. An overnight
weight gain indicates a fluid gain.
1|Page
,At change-of-shift report, the nurse learns the medical diagnoses for four patients. Which
patient should the nurse assess most carefully for development of hyponatremia?
a. Vomiting all day and not replacing any fluid
b. Tumor that secretes excessive antidiuretic hormone (ADH)
c. Tumor that secretes excessive aldosterone
d. Tumor that destroyed the posterior pituitary gland -
ANS: B
ADH causes renal reabsorption of water, which dilutes the body fluids. Excessive ADH thus
causes hyponatremia. Excessive aldosterone causes ECV excess rather than hyponatremia.
The posterior pituitary gland releases ADH; lack of ADH causes hypernatremia. Vomiting
without fluid replacement causes ECV deficit and hypernatremia.
The patient is receiving tube feedings due to a jaw surgery. What change in assessment
findings should prompt the nurse to request an order for serum sodium concentration?
a. Development of ankle or sacral edema
b. Increased skin tenting and dry mouth
c. Postural hypotension and tachycardia
d. Decreased level of consciousness -
ANS: D
Tube feedings pose a risk for hypernatremia unless adequate water is administered between
tube feedings. Hypernatremia causes the level of consciousness to decrease. The serum
sodium concentration is a laboratory measure for osmolality imbalances, not ECV
imbalances. Edema is a sign of ECV excess, not hypernatremia. Skin tenting, dry mouth,
postural hypotension, and tachycardia all can be signs of ECV deficit.
6. The patient with which diagnosis should have the highest priority for teaching regarding
foods that are high in magnesium?
a.Severe hemorrhage
b.Diabetes insipidus
c.Oliguric renal disease
d.Adrenal insufficiency -
ANS: C
When renal excretion is decreased, magnesium intake must be decreased also, to prevent
hypermagnesemia. The other conditions are not likely to require adjustment of magnesium
intake.
The patient's laboratory report today indicates severe hypokalemia, and the nurse has notified
the physician. Nursing assessment indicates that heart rhythm is regular. What is the most
important nursing intervention for this patient now?
a.Raise bed side rails due to potential decreased level of consciousness and confusion.
b.Examine sacral area and patient's heels for skin breakdown due to potential edema.
c.Establish seizure precautions due to potential muscle twitching, cramps, and seizures.
d.Institute fall precautions due to potential postural hypotension and weak leg muscles. -
ANS: D
Hypokalemia can cause postural hypotension and bilateral muscle weakness, especially in the
lower extremities. Both of these increase the risk of falls. Hypokalemia does not cause
edema, decreased level of consciousness, or seizures.
The home health nurse is caring for a patient with a diagnosis of acute immunodeficiency
syndrome (AIDS) who has chronic diarrhea. Which assessments should the nurse use to
2|Page
,detect the fluid and electrolyte imbalances for which the patient has high risk? (Select all that
apply.)
a.
Bilateral ankle edema
b.
Weaker leg muscles than usual
c.
Postural blood pressure and heart rate
d.
Positive Trousseau's sign
e.
Flat neck veins when upright
f.
Decreased patellar reflexes -
(B, C, D)
Chronic diarrhea has high risk of causing ECV deficit, hypokalemia, hypocalcemia, and
hypomagnesemia because it increases fecal excretion of sodium-containing fluid, potassium,
calcium, and magnesium. Appropriate assessments include postural blood pressure and heart
rate for ECV deficit; weaker leg muscles than usual for hypokalemia; and positive
Trousseau's sign for hypocalcemia and hypomagnesemia. Bilateral ankle edema is a sign of
ECV excess, which is not likely with chronic diarrhea. Flat neck veins when upright is a
normal finding. Decreased patellar reflexes is associated with hypermagnesemia, which is not
likely with chronic diarrhea.
The patient has recent bilateral, above-the-knee amputations and has developed C. difficile
diarrhea. What assessments should the nurse use to detect ECV deficit in this patient? (Select
all that apply.)
a.Test for skin tenting.
b.Measure rate and character of pulse.
c.Measure postural blood pressure and heart rate.
d.Check Trousseau's sign.
e.Observe for flatness of neck veins when upright.
f.Observe for flatness of neck veins when supine. -
ANS: A, B, F
ECV deficit is characterized by skin tenting; rapid, thready pulse; and flat neck veins when
supine, which can be assessed in this patient. Although ECV deficit also causes postural
blood pressure drop with tachycardia, this assessment is not appropriate for a patient with
recent bilateral, above-the-knee amputations. Trousseau's sign is a test for increased
neuromuscular excitability, which is not characteristic of ECV deficit. Flat neck veins when
upright is a normal finding.
What substance is released from the posterior pituitary gland and promotes water retention in
the renal system?
A. Renin
B. Aldosterone
C.Angiotensin
D. Antidiuretic hormone (ADH) -
ANS: D
3|Page
, ADH is released in response to increased osmolality and decreased volume of intravascular
fluid; it promotes water retention in the renal system by increasing the permeability of renal
tubules to water. Renin release is stimulated by diminished blood flow to the kidneys.
Aldosterone is secreted by the adrenal cortex. It enhances sodium reabsorption in renal
tubules, promoting osmotic reabsorption of water. Renin reacts with a plasma globulin to
generate angiotensin, which is a powerful vasoconstrictor. Angiotensin also stimulates the
release of aldosterone.
Nurses should be alert for increased fluid requirements in which circumstance?
A. Fever
B. Mechanical Ventilation
C. Congestive Heart Failure
D. Increased intracranial pressure -
ANS: A
Fever leads to great insensible fluid loss in young children because of increased body surface
area relative to fluid volume. The mechanically ventilated child has decreased fluid
requirements. Congestive heart failure is a case of fluid overload in children. Increased
intracranial pressure does not lead to increased fluid requirements in children.
What factor predisposes an infant to fluid imbalances?
A. Decreased surface area
B. Lower metabolic rate
C. Immature kidney functioning
D. Decreased daily exchange of extracellular fluid -
ANS: C
The infants kidneys are functionally immature at birth and are inefficient in excreting waste
products of metabolism. Infants have a relatively high body surface area (BSA) compared
with adults. This allows a higher loss of fluid to the environment. A higher metabolic rate is
present as a result of the higher BSA in relation to active metabolic tissue. The higher
metabolic rate increases heat production, which results in greater insensible water loss.
Infants have a greater exchange of extracellular fluid, leaving them with a reduced fluid
reserve in conditions of dehydration.
What is the required number of milliliters of fluid needed per day for a 14-kg child?
A. 800
B. 1000
C. 1200
D. 1400 -
ANS: C
For the first 10 kg of body weight, a child requires 100 ml/kg. For each additional kilogram
of body weight, an extra 50 ml is needed.
10 kg 100 ml/kg/day = 1000 ml4 kg 50 ml/kg/day = 200 ml1000 ml + 200 ml = 1200
ml/dayEight hundred to 1000 ml is too little; 1400 ml is too much.
An infant is brought to the emergency department with the following clinical manifestations:
poor skin turgor, weight loss, lethargy, tachycardia, and tachypnea. This is suggestive of
which situation?
a. Water excess
4|Page
The nurse is admitting an older adult with decompensated congestive heart failure. The
nursing assessment reveals adventitious lung sounds, dyspnea, and orthopnea. The nurse
should question which doctor's order?
A. Intravenous (IV) 500 mL of 0.9% NaCl at 125 mL/hr
B.Furosemide (Lasix) 20 mg PO now
C. Oxygen via face mask at 8 L/min
D. KCl 20 mEq PO two times per day -
ANS: A
A patient with decompensated heart failure has extracellular fluid volume (ECV) excess. The
IV of 0.9% NaCl is normal saline, which should be questioned because it would expand ECV
and place an additional load on the failing heart. Diuretics such as furosemide are appropriate
to decrease the ECV during heart failure. Increasing the potassium intake with KCl is
appropriate, because furosemide increases potassium excretion. Oxygen administration is
appropriate in this situation of near pulmonary edema from ECV excess.
The nurse assessed four patients at the beginning of the shift. Which finding should the nurse
report immediately to the physician?
A. Swollen ankles in patient with compensated heart failure
B. Positive Chvostek's sign in patient with acute pancreatitis
C. Dry mucous membranes in patient taking a new diuretic
D. Constipation in patient who has advanced breast cancer -
ANS: B
Positive Chvostek's sign indicates increased neuromuscular excitability, which can progress
to dangerous laryngospasm or seizures and thus needs to be reported first. The other
assessment findings are less urgent and need further assessment. Bilateral ankle edema is a
sign of ECV excess, and follow-up is needed, but the situation is not immediately life-
threatening. Dry mucous membranes in a patient taking a diuretic may be associated with
ECV deficit; however, additional assessments of ECV deficit are required before reporting to
the physician. Constipation has many causes, including hypercalcemia and opioid analgesics,
and it needs action, but not as urgently as a positive Chvostek's sign.
The nurse is assessing a patient before hanging an IV solution of 0.9% NaCl with KCl in it.
Which assessment finding should cause the nurse to hold the IV solution and contact the
physician?
a. Weight gain of 2 pounds since last week
b.Dry mucous membranes and skin tenting
c.Urine output 8 mL/hr
d.Blood pressure 98/58 -
ANS: C
Administering IV potassium to a patient who has oliguria is not safe, because potassium
intake faster than potassium output can cause hyperkalemia with dangerous cardiac
dysrhythmias. Dry mucous membranes, skin tenting, and blood pressure 98/58 are consistent
with the need for IV 0.9% NaCl. Weight gain of 2 pounds in a week does not necessarily
indicate fluid overload, because it can be from increased nutritional intake. An overnight
weight gain indicates a fluid gain.
1|Page
,At change-of-shift report, the nurse learns the medical diagnoses for four patients. Which
patient should the nurse assess most carefully for development of hyponatremia?
a. Vomiting all day and not replacing any fluid
b. Tumor that secretes excessive antidiuretic hormone (ADH)
c. Tumor that secretes excessive aldosterone
d. Tumor that destroyed the posterior pituitary gland -
ANS: B
ADH causes renal reabsorption of water, which dilutes the body fluids. Excessive ADH thus
causes hyponatremia. Excessive aldosterone causes ECV excess rather than hyponatremia.
The posterior pituitary gland releases ADH; lack of ADH causes hypernatremia. Vomiting
without fluid replacement causes ECV deficit and hypernatremia.
The patient is receiving tube feedings due to a jaw surgery. What change in assessment
findings should prompt the nurse to request an order for serum sodium concentration?
a. Development of ankle or sacral edema
b. Increased skin tenting and dry mouth
c. Postural hypotension and tachycardia
d. Decreased level of consciousness -
ANS: D
Tube feedings pose a risk for hypernatremia unless adequate water is administered between
tube feedings. Hypernatremia causes the level of consciousness to decrease. The serum
sodium concentration is a laboratory measure for osmolality imbalances, not ECV
imbalances. Edema is a sign of ECV excess, not hypernatremia. Skin tenting, dry mouth,
postural hypotension, and tachycardia all can be signs of ECV deficit.
6. The patient with which diagnosis should have the highest priority for teaching regarding
foods that are high in magnesium?
a.Severe hemorrhage
b.Diabetes insipidus
c.Oliguric renal disease
d.Adrenal insufficiency -
ANS: C
When renal excretion is decreased, magnesium intake must be decreased also, to prevent
hypermagnesemia. The other conditions are not likely to require adjustment of magnesium
intake.
The patient's laboratory report today indicates severe hypokalemia, and the nurse has notified
the physician. Nursing assessment indicates that heart rhythm is regular. What is the most
important nursing intervention for this patient now?
a.Raise bed side rails due to potential decreased level of consciousness and confusion.
b.Examine sacral area and patient's heels for skin breakdown due to potential edema.
c.Establish seizure precautions due to potential muscle twitching, cramps, and seizures.
d.Institute fall precautions due to potential postural hypotension and weak leg muscles. -
ANS: D
Hypokalemia can cause postural hypotension and bilateral muscle weakness, especially in the
lower extremities. Both of these increase the risk of falls. Hypokalemia does not cause
edema, decreased level of consciousness, or seizures.
The home health nurse is caring for a patient with a diagnosis of acute immunodeficiency
syndrome (AIDS) who has chronic diarrhea. Which assessments should the nurse use to
2|Page
,detect the fluid and electrolyte imbalances for which the patient has high risk? (Select all that
apply.)
a.
Bilateral ankle edema
b.
Weaker leg muscles than usual
c.
Postural blood pressure and heart rate
d.
Positive Trousseau's sign
e.
Flat neck veins when upright
f.
Decreased patellar reflexes -
(B, C, D)
Chronic diarrhea has high risk of causing ECV deficit, hypokalemia, hypocalcemia, and
hypomagnesemia because it increases fecal excretion of sodium-containing fluid, potassium,
calcium, and magnesium. Appropriate assessments include postural blood pressure and heart
rate for ECV deficit; weaker leg muscles than usual for hypokalemia; and positive
Trousseau's sign for hypocalcemia and hypomagnesemia. Bilateral ankle edema is a sign of
ECV excess, which is not likely with chronic diarrhea. Flat neck veins when upright is a
normal finding. Decreased patellar reflexes is associated with hypermagnesemia, which is not
likely with chronic diarrhea.
The patient has recent bilateral, above-the-knee amputations and has developed C. difficile
diarrhea. What assessments should the nurse use to detect ECV deficit in this patient? (Select
all that apply.)
a.Test for skin tenting.
b.Measure rate and character of pulse.
c.Measure postural blood pressure and heart rate.
d.Check Trousseau's sign.
e.Observe for flatness of neck veins when upright.
f.Observe for flatness of neck veins when supine. -
ANS: A, B, F
ECV deficit is characterized by skin tenting; rapid, thready pulse; and flat neck veins when
supine, which can be assessed in this patient. Although ECV deficit also causes postural
blood pressure drop with tachycardia, this assessment is not appropriate for a patient with
recent bilateral, above-the-knee amputations. Trousseau's sign is a test for increased
neuromuscular excitability, which is not characteristic of ECV deficit. Flat neck veins when
upright is a normal finding.
What substance is released from the posterior pituitary gland and promotes water retention in
the renal system?
A. Renin
B. Aldosterone
C.Angiotensin
D. Antidiuretic hormone (ADH) -
ANS: D
3|Page
, ADH is released in response to increased osmolality and decreased volume of intravascular
fluid; it promotes water retention in the renal system by increasing the permeability of renal
tubules to water. Renin release is stimulated by diminished blood flow to the kidneys.
Aldosterone is secreted by the adrenal cortex. It enhances sodium reabsorption in renal
tubules, promoting osmotic reabsorption of water. Renin reacts with a plasma globulin to
generate angiotensin, which is a powerful vasoconstrictor. Angiotensin also stimulates the
release of aldosterone.
Nurses should be alert for increased fluid requirements in which circumstance?
A. Fever
B. Mechanical Ventilation
C. Congestive Heart Failure
D. Increased intracranial pressure -
ANS: A
Fever leads to great insensible fluid loss in young children because of increased body surface
area relative to fluid volume. The mechanically ventilated child has decreased fluid
requirements. Congestive heart failure is a case of fluid overload in children. Increased
intracranial pressure does not lead to increased fluid requirements in children.
What factor predisposes an infant to fluid imbalances?
A. Decreased surface area
B. Lower metabolic rate
C. Immature kidney functioning
D. Decreased daily exchange of extracellular fluid -
ANS: C
The infants kidneys are functionally immature at birth and are inefficient in excreting waste
products of metabolism. Infants have a relatively high body surface area (BSA) compared
with adults. This allows a higher loss of fluid to the environment. A higher metabolic rate is
present as a result of the higher BSA in relation to active metabolic tissue. The higher
metabolic rate increases heat production, which results in greater insensible water loss.
Infants have a greater exchange of extracellular fluid, leaving them with a reduced fluid
reserve in conditions of dehydration.
What is the required number of milliliters of fluid needed per day for a 14-kg child?
A. 800
B. 1000
C. 1200
D. 1400 -
ANS: C
For the first 10 kg of body weight, a child requires 100 ml/kg. For each additional kilogram
of body weight, an extra 50 ml is needed.
10 kg 100 ml/kg/day = 1000 ml4 kg 50 ml/kg/day = 200 ml1000 ml + 200 ml = 1200
ml/dayEight hundred to 1000 ml is too little; 1400 ml is too much.
An infant is brought to the emergency department with the following clinical manifestations:
poor skin turgor, weight loss, lethargy, tachycardia, and tachypnea. This is suggestive of
which situation?
a. Water excess
4|Page
