Deck 24: Fluid and Electrolyte Homeostasis and Imbalances

Question 1

Decreased neuromuscular excitability can be seen in which two electrolyte disorders?

A) Hypercalcemia and hypermagnesemia
B) Hyponatremia and hyperkalemia
C) Hypocalcemia and hypokalemia
D) Hypernatremia and hypomagnesemia

Answer 1

Hypercalcemia and hypermagnesemia

Question 2

Hypermagnesemia and hypercalcemia both cause excessive neuromuscular excitability.

Answer 2

False

Question 3

Administration of 5% dextrose in water (D₅W) is an effective way to manage saline deficit.

Answer 3

False

Question 4

Filtration and diffusion are passive mechanisms of capillary transport.

Question 5

One liter of fluid weighs about one pound.

Question 6

Which of the following statements best describes the pathophysiologic process of hypernatremia?

A) Saline excess leads to weight gain, edema, and congestive heart failure.
B) Increased extracellular osmolality leads to cellular shriveling.
C) Excess extracellular water leads to swelling of body cells.
D) Sodium excess leads to excessive water retention.

Question 7

If an individual with normal fluid balance is given 2 L of normal saline, how will this fluid distribute in the body (assuming no excretion)?

A) 50% extracellular, 50% intracellular
B) Two thirds extracellular, one third intracellular
C) All intravascular
D) All extracellular

Question 8

Patients with water deficit have an elevated serum osmolality.

Question 9

Hypernatremia causes cells to accumulate sodium and water so that they swell.

Question 10

Abnormalities in intracellular regulation of enzyme activity and cellular production of ATP are associated with

A) hyponatremia.
B) hypocalcemia.
C) hypophosphatemia.
D) hypokalemia.

Question 11

Which of the following serum electrolyte values is abnormal?

A) Magnesium 2.0 mEq/L
B) Potassium 4.0 mEq/L
C) Calcium 10.0 mEq/L
D) Phosphate 4.0 mg/dl

Question 12

An increase in the resting membrane potential (hyperpolarized) is associated with

A) hypokalemia.
B) hyperkalemia.
C) hypocalcemia.
D) hypercalcemia.

Question 13

The primary force promoting fluid movement from the capillary to the interstitium is capillary oncotic pressure.

Question 14

Patients with pure saline deficit have normal serum sodium concentrations.

Question 15

Which of the following is likely to lead to hyponatremia?

A) Insufficient ADH secretion
B) Excess aldosterone secretion
C) Administration of intravenous normal saline
D) Frequent nasogastric tube irrigation with water

Question 16

Orthostatic hypotension is a manifestation of saline deficit.

Question 17

The most appropriate therapy for an individual with hypernatremia is

A) volume expansion with normal saline.
B) administration of colloids.
C) hypotonic fluids.
D) diuretics.

Question 18

The best indicator of extracellular (saline) volume status would be

A) serum sodium ion.
B) serum osmolality.
C) weight change.
D) serum potassium ion.

Question 19

Osmoreceptors located in the hypothalamus control the release of

A) angiotensin.
B) atrial natriuretic peptide.
C) aldosterone.
D) vasopressin (antidiuretic hormone, ADH).

Question 20

Two thirds of body fluids are within the intracellular fluid compartments.

Question 21

After a patient has received fluid therapy for several hours, her supine and standing heart rate and blood pressure are recorded. Which of the following results indicates a need for further therapy?

A) Supine HR 88, BP 100/80; standing HR 85, BP 96/78
B) Supine HR 88, BP 100/80; standing HR 90, BP 110/80
C) Supine HR 88, BP 100/80; standing HR 110, BP 98/78
D) Supine HR 88, BP 100/80; standing HR 90, BP 98/78

Question 22

A patient's serum sodium level upon admission was 148 mEq/L, her heart rate was 110 lying supine, and her blood pressure was 88/60. What is the most appropriate fluid therapy?

A) Push oral fluids.
B) Free water restriction.
C) Administer IV 5% dextrose in water (D₅W).
D) Administer IV normal saline (0.9%).

Question 23

A serum sodium level is obtained and shows a level of 142 mEq/L. Which of the following is a correct interpretation of this value?

A) Indicative of water excess
B) Indicative of saline deficit
C) Indicative of water deficit
D) Normal value

Question 24

A 14-month-old girl is brought to urgent care by her parents for persistent fever, vomiting, and diarrhea. Upon questioning, the parents report that the child has had only one to two wet diapers per day for the last 2 days. The child's weight is noted to be 2 pounds less than her normal weight. This is equivalent to approximately how much fluid loss?

A) One fourth of a liter
B) One half of a liter
C) Two liters
D) One liter

Question 25

Which fluid will be most effective in restoring extracellular volume?

A) 5% dextrose in water (D₅W)
B) Normal saline (0.9%)
C) Half normal saline (0.045%)
D) 10% dextrose in water (D₁₀W)

Question 26

Because of continuing decreased urine output, the function of a patient's kidneys is evaluated with urine electrolytes. The urine Na⁺ is found to be quite low. This is most likely due to

A) kidney failure.
B) atrial natriuretic effect on kidney tubules.
C) aldosterone effect on kidney tubules.
D) antidiuretic effect on kidney tubules.

Question 27

An electrolyte disorder that frequently accompanies ketoacidosis is

A) hyponatremia.
B) hypochloremia.
C) hypokalemia.
D) hyperkalemia.

Question 28

C.G. is a 42-year-old patient with type 1 diabetes that is normally well controlled with insulin. Three days ago, she developed a viral infection with high fever and has not been checking her blood glucose regularly. She is now in the emergency department complaining of abdominal pain and flu symptoms. C.G.'s urine is positive for glucose and ketones, and serum glucose and blood gases are obtained. What fluid balance problem is C.G. at risk for secondary to glycosuria?

A) Water deficit
B) Water excess
C) Hyponatremia
D) Saline excess