Chapter 17 Fluid, Electrolyte, and Acid-Base Imbalances VOCAB

Question 1

Acidosis

Answer 1

blood pH below 7.35

Question 2

Active transport

Answer 2

a process in which molecules move against the concentration gradient. External energy is required for this process. An example is the sodium-potassium pump

Question 3

Alkalosis

Answer 3

blood pH above 7.45

Question 4

Anions

Answer 4

negatively charged ions

Question 5

Buffers

Answer 5

act chemically to change strong acids into weaker acids or to bind acids to neutralize their effect (primary regulator of acid-base balance)

Question 6

Cations

Answer 6

positively charged ions

Question 7

Central Venous Access Devices (CVADs)

Answer 7

catheters placed in large blood vessels (e.g., subclavian vein, jugular vein) of people who require frequent or special access to the vascular system

Question 8

Electrolytes

Answer 8

substances whose molecules dissociate, or split into ions, when placed in water

Question 9

Fluid spacing

Answer 9

a term used to describe the distribution of body water

Question 10

Hydrostatic pressure

Answer 10

the force that fluid exerts within a compartment.

Question 11

Hypertonic

Answer 11

a solution that increases the degree of osmotic pressure on a semipermeable membrane.

Question 12

Hypotonic

Answer 12

a solution that has a lower concentration of solute than another solution, thus exerting less osmotic pressure on a semipermeable membrane.

Question 13

Isotonic

Answer 13

fluids with the same osmolality as the cell interior

Question 14

Oncotic pressure

Answer 14

the osmotic pressure of a colloid in solution.

Question 15

Osmolality

Answer 15

the number of milliosmoles per kilogram of water, or the concentration of molecules per weight of water

Question 16

Osmosis

Answer 16

the movement of water “down” a concentration gradient, that is, from a region of low solute concentration to one of high solute concentration, across a semipermeable membrane

Question 17

Osmotic pressure

Answer 17

measured in milliosmoles (mOsm) and may be expressed as either fluid osmolarity or fluid osmolality

Question 18

1. During the postoperative care of a 76-year-old patient, the nurse monitors the patient’s intake and output carefully, knowing that the patient is at risk for fluid and electrolyte imbalances primarily because
   a. older adults have an impaired thirst mechanism and need reminding to drink fluids.
   b. water accounts for a greater percentage of body weight in the older adult than in younger adults.
   c. older adults are more likely than younger adults to lose extracellular fluid during surgical procedures.
   d. small losses of fluid are more significant because body fluids account for only about 50% of body weight in older adults.

Answer 18

1. d,

Question 19

2. During administration of a hypertonic IV solution, the mechanism involved in equalizing the fluid concentration between ECF and the cells is
   a. osmosis.
   b. diffusion.
   c. active transport.
   d. facilitated diffusion.

Answer 19

2. a,

Question 20

3a. An older woman was admitted to the medical unit with dehydration. Clinical indications of this problem are (select all that apply)

a. weight loss.
b. dry oral mucosa.
c. full bounding pulse.
d. engorged neck veins.
e. decreased central venous pressure.

Answer 20

3a. a, b, e,

Question 21

3b. The nursing care for a patient with hyponatremia includes
a. fluid restriction.
b. administration of hypotonic IV fluids.
c. administration of a cation-exchange resin.
d. increased water intake for patients on nasogastric suction.

Answer 21

3b. a,

Question 22

3c. The nurse should be alert for which manifestations in a patient receiving a loop diuretic?
a. Restlessness and agitation
b. Paresthesias and irritability
c. Weak, irregular pulse and poor muscle tone
d. Increased blood pressure and muscle spasms

Answer 22

3c. c,

Question 23

3d. Which patient would be at greatest risk for the potential development of hypermagnesemia?
a. 83-year-old man with lung cancer and hypertension
b. 65-year-old woman with hypertension taking β-adrenergic blockers
c. 42-year-old woman with systemic lupus erythematosus and renal failure
d. 50-year-old man with benign prostatic hyperplasia and a urinary tract infection

Answer 23

3d. c,

Question 24

3e. It is especially important for the nurse to assess for which clinical manifestation(s) in a patient who has just undergone a total thyroidectomy (select all that apply)?

a. Confusion
b. Weight gain
c. Depressed reflexes
d. Circumoral numbness
e. Positive Chvostek’s sign

Answer 24

3e. a, d, e,

Question 25

3f. The nurse anticipates that treatment of the patient with hyperphosphatemia secondary to renal failure will include
a. fluid restriction.
b. calcium supplements.
c. loop diuretic therapy.
d. magnesium supplements.

Answer 25

3f. b,

Question 26

4. The lungs act as an acid-base buffer by
   a. increasing respiratory rate and depth when CO2 levels in the blood are high, reducing acid load.
   b. increasing respiratory rate and depth when CO2 levels in the blood are low, reducing base load.
   c. decreasing respiratory rate and depth when CO2 levels in the blood are high, reducing acid load.
   d. decreasing respiratory rate and depth when CO2 levels in the blood are low, increasing acid load.

Answer 26

4. a,

Question 27

5. A patient has the following arterial blood gas results: pH 7.52; PaCO2 30 mm Hg; HCO3− 24 mEq/L. The nurse determines that these results indicate
   a. metabolic acidosis.
   b. metabolic alkalosis.
   c. respiratory acidosis.
   d. respiratory alkalosis.

Answer 27

5. d,

Question 28

6. The typical fluid replacement for the patient with a fluid volume deficit is
   a. dextran.
   b. 0.45% saline.
   c. lactated Ringer’s.
   d. 5% dextrose in 0.45% saline.

Answer 28

6. c,

Question 29

7. The nurse is unable to flush a central venous access device and suspects occlusion. The best nursing intervention would be to
   a. apply warm moist compresses to the insertion site.
   b. attempt to force 10 mL of normal saline into the device.
   c. place the patient on the left side with head-down position.
   d. instruct the patient to change positions, raise arm, and cough.

Answer 29

7. d

Question 30

1. A 50-year-old woman with hypertension has a serum potassium level that has acutely risen to 6.2 mEq/L. Which type of order, if written by the health care provider, should be questioned by the nurse?

A. Limit foods high in potassium

B. Spironolactone (Aldactone) daily

C. Calcium gluconate IV piggyback

D. Administer intravenous insulin and glucose

Answer 30

B. Spironolactone (Aldactone) daily

Rationale
Spironolactone (Aldactone) is a potassium-sparing diuretic that inhibits the exchange of sodium for potassium in the distal renal tubule and helps to prevent potassium loss. Spironolactone is contraindicated in a patient with hyperkalemia (serum potassium >5.0 mEq/L). Collaborative management for patients with hyperkalemia may include limiting foods high in potassium, IV insulin and glucose, administration of calcium gluconate, potassium-wasting diuretics (e.g., furosemide [Lasix]), hemodialysis, sodium polystyrene sulfonate (Kayexalate), and IV fluid administration.

Pre-Test

Question 31

2. The nurse is caring for a 76-year-old woman admitted to the clinical unit with hypernatremia and dehydration after prolonged fever. Which beverage would be safest for the nurse to offer the patient?

A. Malted milk

B. Orange juice

C. Tomato juice

D. Hot chocolate

Answer 31

B. Orange juice

Rationale
Orange juice has the least amount of sodium (approximately 2 mg in 8 ounces). Hot chocolate has approximately 75 mg sodium in 8 ounces. Tomato juice has approximately 650 mg sodium in 8 ounces. Malted milk has approximately 625 mg sodium in 8 ounces.

Pre-Test

Question 32

3. The nurse on a medical-surgical unit identifies that which patient has the highest risk for metabolic alkalosis?

A. A patient with a traumatic brain injury

B. A patient with type 1 diabetes mellitus

C. A patient with acute respiratory failure

D. A patient with nasogastric tube suction

Answer 32

D. A patient with nasogastric tube suction

Rationale
Excessive nasogastric suctioning may cause metabolic alkalosis. Brain injury may cause hyperventilation and respiratory alkalosis. Type 1 diabetes mellitus (diabetic ketoacidosis) is associated with metabolic acidosis. Acute respiratory failure may lead to respiratory acidosis.

Pre-Test

Question 33

4. A 22-year-old male is admitted to the emergency department with a stab wound to the abdomen. The patient’s vital signs are blood pressure 82/56 mm Hg, pulse 132 beats/minute, respirations 28 breaths/minute, and temperature 97.9° F (36.6° C). Which fluid, if ordered by the health care provider, should the nurse question?

A. 0.9% saline

B. 0.45% saline

C. Packed red blood cells

D. Lactated Ringer’s solution

Answer 33

B. 0.45% saline

Rationale
IV administration of 0.45% saline is hypotonic and is used for maintenance fluid replacement and dilutes the extracellular fluid. Intravenous solutions used for volume expansion for hypovolemic shock include lactated Ringer’s solution and 0.9% saline. If hypovolemia is due to blood loss, blood may be administered.

Pre-Test

Question 34

5. A 46-year-old woman with a subclavian triple-lumen catheter is transferred from a critical care unit after an extended stay for respiratory failure. Which action is important for the nurse to take?

A. Change the injection cap after the administration of IV medications.

B. Use a 5-mL syringe to flush the catheter between medications and after use.

C. During removal of the catheter, have the patient perform the Valsalva maneuver.

D. If resistance is met when flushing, use the push-pause technique to dislodge the clot.

Answer 34

C. During removal of the catheter, have the patient perform the Valsalva maneuver.

Rationale
The nurse should withdraw the catheter while the patient performs the Valsalva maneuver to prevent an air embolism. Injection caps should be changed at regular intervals but not routinely after medications. Flushing should be performed with at least a 10-mL syringe to avoid excess pressure on the catheter. If resistance is encountered during flushing, force should not be applied. The push-pause method is preferred for flushing catheters but not used if resistance is encountered during flushing.

Pre-Test