Chapter 25 Determinants and Assessment of Fluid and Electrolyte Balance

Question 1

1) A patient with hypoxia is at risk for disruption of the sodium potassium pump. Which would the nurse expect if this occurs?
1. Decreased serum potassium
2. Cell death
3. Increase in the cells’ ability to use active transport
4. Decreased extracellular fluid

Answer 1

Answer: 2

Explanation:
1. The amount of potassium in the extracellular fluids would increase.

2. Without the counterregulating forces provided by the sodium potassium pump, cells will fill with fluid and will rupture and die.
3. Dysfunction of the sodium potassium pump will not increase the cells’ ability to use active transport.
4. Since the cells can no longer hold fluid, the extracellular fluid component increases.

Question 2

2) A patient is admitted with bleeding from the gastrointestinal tract. The nurse plans interventions to support the balance of which fluid volume compartment?
1. Transcellular
2. Intravascular
3. Interstitial
4. Intracellular

Answer 2

Answer: 2

Explanation: 1. Transcellular fluid is cerebral spinal fluid, peritoneal fluid, and synovial fluid.

2. Intravascular fluid is one extracellular compartment that consists of plasma. In the case of bleeding, the fluid compartment that will be affected first will be the intravascular fluid.
3. Interstitial fluid is found between the cells.
4. Intracellular fluid is that fluid found within the cells.

Question 3

3) The nurse is planning the care of a patient in the intensive care unit. With regard to maintaining adequate fluid volume for this patient, the nurse realizes that interventions should be planned to reduce the risk of which condition?
1. Retention of potassium
2. Retention of sodium
3. Loss of calcium
4. Loss of magnesium

Answer 3

Answer: 2
Explanation:
1. Most intensive care patients experience a reduced potassium level and do not retain potassium. As retention of a different electrolyte occurs, potassium is excreted by the kidney.

2. Under normal situations, the regulation of water is through the thirst mechanism. In the intensive care unit, however, many patients have altered levels of consciousness and will not have this mechanism in place. Because of this, hypernatremia or retention of sodium is a common electrolyte imbalance in these types of patients.
3. Calcium balance is not typically associated with fluid volume.
4. Magnesium balance is not typically associated with fluid volume

Question 4

4) A patient in the intensive care unit has low blood pressure. If the patient’s baroreceptors are functioning appropriately, what will the nurse assess in this patient?
1. Reduced urine output
2. Weak hand grasps
3. Decreased level of consciousness
4. Peripheral edema

Answer 4

Explanation: 1. Arterial baroreceptors are in the arch of the aorta and carotid sinus. These receptors detect arterial pressure changes. When they sense a decrease in arterial blood pressure, they signal the autonomic nervous system, which will cause peripheral vasoconstriction to raise the blood pressure. Vasoconstriction of the renal arteries decreases glomerular filtration, which will reduce the urine output.

2. Weak hand grasps may or may not occur in the patient with hypotension and are not associated with baroreceptor response.
3. Decreased level of consciousness (LOC) is not always present in patients with hypotension. Decreased LOC is not related to baroreceptor response.
4. Peripheral edema may or may not be seen in patients with low blood pressure. Peripheral edema is not related to baroreceptor response

Question 5

5) The nurse is reviewing laboratory results for a patient just admitted to the intensive care unit. The nurse would anticipate interventions to be necessary for which values?
Note: Credit will be given only if all correct choices and no incorrect choices are selected.
Select all that apply.
1. Calcium 8 mg/dL
2. Potassium 3 mEq/L
3. Sodium 142 mEq/L
4. Phosphate 1.8 mEq/L
5. Magnesium 2.1 mEq/L

Answer 5

Answer: 1, 2
Explanation:
1. The normal range for serum calcium is 9 to 11 mg/dL. A low value may indicate need for intervention

2. The normal range for potassium is 3.5 to 5.3 mEq/L. A low value would indicate need for supplementation.
3. The normal range for serum sodium is between 135 to 145 mEq/L.
4. The normal range for serum phosphate is 1.7 to 2.6 mEq/L.
5. The normal range for serum magnesium is 1.5 to 2.5 mEq/L.

Question 6

6) Which laboratory value would require that the nurse closely monitor a patient’s cardiac rhythm?
1. Chloride 94 mEq/L
2. Calcium 2.2 mmol/L
3. Potassium 3.3 mEq/L
4. Phosphate 3 mg/dL

Answer 6

Answer: 3

Explanation:
1. This chloride level is slightly lower than normal but would not cause cardiac rhythm disturbances.

2. This normal calcium level would not be implicated in cardiac rhythm disturbances.
3. Both high and low potassium levels can adversely affect cardiac rhythm.
4. This normal phosphate level would not adversely affect cardiac rhythm.

Question 7

7) The nurse notes that a patient’s serum albumin level is elevated. Which other lab result should the nurse review?
1. Potassium
2. Calcium
3. Sodium
4. Chloride

Answer 7

Answer: 2

Explanation:
1. Changes in albumin level should not change potassium level.

2. Ionized calcium is the calcium used in physiological activities such as neuromuscular activity. The concentration of ionized calcium is inversely proportional to the albumin concentration, so the higher the serum albumin, the lower the plasma ionized calcium.
3. Albumin level does not affect sodium level.
4. Chloride level is not affected by albumin level.

Question 8

8) A patient’s potassium and calcium levels are below the normal range. The nurse should check for a decreased level of which other electrolyte?
1. Phosphorous
2. Sodium
3. Magnesium
4. Chloride

Answer 8

Answer: 3

Explanation:
1. The phosphorous level might be elevated since phosphorous has an inverse relationship to calcium.

2. Sodium level will not be affected.
3. Because magnesium is mainly excreted in the feces and a small amount is excreted through the urine, these mechanisms of excretion and conservation are similar to those of potassium and calcium. If the patient’s potassium and calcium levels are low, the patient might also demonstrate a low magnesium level since magnesium balance is closely related to potassium and calcium balance.
4. Chloride level will not be affected

Question 9

9) While assessing a high-acuity patient, the nurse learns the patient has a history of arthritis. Which question would provide the most information regarding potential impact on the patient’s fluid and electrolyte balance?
1. “How well are you able to take care of your daily needs?”
2. “How well do you sleep?”
3. “How often do you take nonsteroidal anti-inflammatory medications?”
4. “Does your arthritis affect mostly your hands or your feet and legs?”

Answer 9

Answer: 3
Explanation:
1. Ability to take care of activities of daily living (ADLs) would not have much impact on fluid and electrolyte balance.

2. Sleep has little relationship to fluid and electrolyte balance.
3. One question asked during the nursing history that relates to fluid and electrolyte assessment is if the patient is taking or receiving any medications that can alter the fluid and electrolyte balance. One such type of medication is nonsteroidal anti-inflammatory drugs (NSAIDs). The patient has arthritis and could be taking NSAIDs on a regular basis. Therefore, the nurse should assess the patient’s frequency of taking this category of medication, which could impact the fluid and electrolyte status.
4. The body part affected by arthritis would not have an impact on fluid and electrolyte status.

Question 10

10) A patient admitted to the intensive care unit has been taking high levels of magnesium supplements. The nurse would add which information to this patient’s plan of care?
1. Test for presence of Chvostek’s sign.
2. Monitor for sudden decrease in respiratory rate.
3. Monitor for cardiac dysrhythmias.
4. Monitor for hyperthermia.

Answer 10

Answer: 3
Explanation:
1. Chvostek’s sign is positive in hypomagnesemia.

2. A low respiratory rate can be seen with a low magnesium level.
3. Cardiac dysrhythmias have been associated with abnormal magnesium levels.
4. Magnesium does not affect temperature.

Question 11

11) A patient’s temperature has been elevated for the past 24 hours. The nurse should monitor which electrolyte?
1. Phosphorous
2. Sodium
3. Potassium
4. Magnesium

Answer 11

Answer: 2

Explanation:
1. It is unlikely that temperature elevation will affect phosphorus levels.

2. With an elevated temperature, there can be a loss of water and sodium through diaphoresis. The nurse should assess the patient’s sodium level.
3. It is unlikely that temperature elevation will affect potassium level.
4. It is unlikely that temperature level will affect magnesium level.

Question 12

12) Which findings would the nurse evaluate as indication that a pregnant female is hypovolemic?
Note: Credit will be given only if all correct choices and no incorrect choices are selected.
Select all that apply.
1. Flat neck veins
2. Bilateral adventitious lung sounds
3. Flat hand veins when dependent
4. Sunken eyes
5. Tenting of the skin

Answer 12

Answer: 3, 4, 5

Explanation:
1. Flat neck veins are normal and do not indicate hypovolemia. Distended neck veins indicate hypervolemia.

2. Adventitious lung sounds indicate hypervolemia.
3. If hand veins remain flat when in the dependent position, the nurse should suspect that the patient is hypovolemic.
4. Eyes that are sunken in their sockets may indicate hypovolemia.
5. Tenting of the skin reveals poor skin turgor, which can be a result of hypovolemia. This finding is not reliable in older adults.

Question 13

13) When assessing the patient’s edema of the lower extremities, the nurse notes that it takes 3 minutes before the 8-mm indentation created by applying pressure above the ankles disappears. This information should be documented as being which type of pitting edema?
1. +2
2. +1
3. +4
4. +3

Answer 13

Answer: 3

Explanation:
1. Indentations that are 4 mm and disappear within 10 to 15 seconds would be considered +2 pitting edema.

2. Indentations that are 2 mm and disappear rapidly would be considered +1 pitting edema.
3. Indentations that are 8 mm and disappear after 2 to 5 minutes would be considered +4 pitting edema.
4. Indentations that are 6 mm and disappear within 1 to 2 minutes would be considered +3 pitting edema.

Question 14

14) A patient’s BUN/creatinine ratio is 13:1. How would the nurse interpret this finding?
1. The patient is hypervolemic.
2. Renal tubule dysfunction may be present.
3. The patient is normovolemic.
4. The patient’s glomerular filtration rate is decreased

Answer 14

Answer: 3
Explanation:
1. A BUN/creatinine ratio of 13:1 does not indicate hypervolemia.

2. There is no information that supports this interpretation.
3. The normal ratio of BUN to creatinine is 10:1 to 20:1. Based on this value alone, the nurse would evaluate this patient as normovolemic.
4. There is not enough information to make this determination.

Question 15

15) After reviewing a patient’s laboratory values, the nurse determines the patient is experiencing fluid volume deficit. Which laboratory value would the nurse cite as supporting this determination?
1. Serum sodium 140 mEq/L
2. Urine specific gravity of 1.003
3. Urine osmolality 330 mOsm/kg
4. Serum potassium 4.3 mEq/L

Answer 15

Answer: 3
Explanation:
1. This serum sodium level is within normal limits and would not help determine the patient’s hydration status.

2. Low urine specific gravity develops in conditions that cause fluid volume excess.
3. Normal urine osmolality is 280 to 320 mOsm/kg. The urine osmolality will increase during fluid volume deficit because the kidneys retain water. This is the laboratory value that indicates the patient is experiencing fluid volume deficit.
4. This normal serum potassium level would not help determine if the patient is experiencing a fluid volume deficit.

Question 16

16) A patient’s laboratory report indicates critically low serum calcium levels. The nurse would conduct further assessment for which conditions?
Note: Credit will be given only if all correct choices and no incorrect choices are selected.
Select all that apply.
1. Disruption of the parathyroid glands
2. Decreased supply of vitamin D
3. Low levels of calcitonin
4. Insufficient levels of calcitriol
5. Insufficient levels of calcidiol

Answer 16

Answer: 1, 2, 4, 5

Explanation:
1. Parathyroid hormone is essential to the release of calcium from bony tissue into the blood and the conversion of calcidiol to calcitriol.

2. If insufficient amounts of vitamin D are present, calcium absorption in the intestine is reduced.
3. Low levels of calcitonin would result in high calcium levels.
4. Calcitriol is the active form of vitamin D, which causes the small intestine to absorb more calcium. Insufficient levels of calcitriol would result in low serum calcium levels.
5. Calcidiol converts to calcitriol. Insufficient levels would result in low calcium levels.

Question 17

17) The nurse is assessing for the presence of Trousseau sign. Which findings would the nurse evaluate as indicating this sign is present?
Note: Credit will be given only if all correct choices and no incorrect choices are selected.
Select all that apply.
1. The fingers hyperflex.
2. The thumb flexes toward the palm.
3. The fingers hyperextend.
4. The thumb hyperextends.
5. The hand makes a fist

Answer 17

Answer: 2, 3
Explanation:
1. Flexion of the fingers does not indicate positive Trousseau sign.

2. Flexion of the thumb toward the palm indicates a positive Trousseau sign.
3. Hyperextension of the fingers indicates a positive Trousseau sign.
4. Hyperextension of the thumb does not indicate a positive Trousseau sign.
5. Fisting of the hand does not indicate a positive Trousseau sign.

Question 18

18) A urine electrolyte test is ordered to evaluate aldosterone disorder in a patient just admitted to the intensive care unit. How would the nurse collect this specimen?
1. Collect the first specimen voided in the morning.
2. Prepare a 24-hour urine collection system.
3. Collect the specimen from the indwelling urinary catheter inserted in the emergency department.
4. Use a temporary straight catheter to collect the specimen.

Answer 18

Answer: 2

Explanation:
1. This specimen should be collected in a different manner.

2. Urine electrolytes typically require a 24-hour urine specimen.
3. This specimen is not collected in this manner.
4. This specimen is not collected in this manner.

Question 19

19) Which patient would the nurse expect to have the least amount of body fluid?
1. A 75-year-old woman with a body mass index (BMI) in the obese range
2. A 23-year-old female with history of type 1 diabetes
3. A 72-year-old male who had a myocardial infarction at age 50
4. A 16-year-old male who plays football on his high school team

Answer 19

Answer: 1
Explanation: 1. Fat cells contain little water, so obese individuals have less fluid. Women have more body fat than men, so they have less fluid. Older patients tend to have reduced body water.
2. Since this female is young, she will have more body fluid than older females. Diabetes is not a factor.
3. Since this older adult is male, he tends to have more body fluid than women at that age.
4. This patient is young and male, which tends to increase fluid level. The fact that he plays football is not a factor.

Question 20

20) Laboratory testing reveals a patient’s serum osmolality to be 240 mOsm/kg. The nurse would assess for which conditions?
Note: Credit will be given only if all correct choices and no incorrect choices are selected.
Select all that apply.
1. Excessive infusion of D5W
2. Dehydration
3. Hyperglycemia
4. Syndrome of inappropriate ADH (SIADH)
5. Acute kidney injury

Answer 20

Answer: 1, 4

Explanation:
1. Excessive D5W IV intake will result in decreased serum osmolality.

2. Dehydration results in increased serum osmolality.
3. Hyperglycemia results in increased serum osmolality.
4. SIADH will result in decreased serum osmolality.
5. Acute kidney injury results in decreased urine osmolality