Disorders of Fluid Volume, Osmolality, and Electrolytes
Price: Pathophysiology, 6th Edition
Study Questions Chapter 21

1.
ECF volume imbalances are characterized by:
A.Isotonic body fluid losses or gains
B.Relatively greater losses or gains of Na+ than that of water
C.Relatively greater losses or gains of water than that of Na+
D.None of the above

2.
Na+ ions account for what percentage of the osmotically active particles in the ECF?
A.5%
B.15%
C.20%
D.90%

3.
Which of the following effects would result from a decrease of the serum Na+ concentration below the normal range?
A.Shift of water from the ICF to the ECF, causing cell shrinkage
B.Shift of water from the ECF to the ICF, causing cell swelling
C.Shift of water and Na+ from the ECF to the interstitial fluid (ISF), causing edema
D.None of the above

4.
The most common condition that causes a fluid volume deficit is:
A.GI losses (e.g., vomiting, diarrhea) combined with inadequate fluid intake
B.Third-space losses
C.Osmotic diuresis
D.Aldosterone deficiency

5.
Rapid administration of IV fluids can result in pulmonary edema because:
A.Tissue hydrostatic pressure in the lung parenchyma increases
B.Colloid osmotic pressure in the pulmonary vessels increases
C.Hydrostatic pressure in the pulmonary vessels increases
D.Lymphatic clearance in the interstitium increases

6.
You are caring for Mr. Brown, a 75-year-old patient with congestive heart failure who is receiving IV fluids. You notice that he is becoming increasingly restless and short of breath. His blood pressure and respiratory rate are increasing, and he has a moist-sounding cough. You also note that he has neck vein distention up to the jaw angle in the sitting position. You hear medium rales (crackles) throughout both posterior lung fields. Mr. Brown's symptoms are probably caused by:
A.Decreased venous return to the right ventricle
B.Circulatory overload and pulmonary edema
C.Liver congestion from fluid reflux from the heart
D.Increased tissue hydrostatic pressure in the alveoli
E.Decreased hydrostatic pressure in the pulmonary capillaries

7.
The best nursing intervention for Mr. Brown (see question #6) would be:
A.Elevating the foot of the bed to aid venous return
B.Slowing down the IV to a keep open rate and notifying the physician
C.Continuing to monitor the vital signs
D.Encouraging the patient to cough and breathe deeply to improve alveolar ventilation

8.
The first emergency action in the treatment of severe acute pulmonary edema is:
A.Positioning the patient in high Fowler's position with the legs lowered to reduce hydrostatic pressure in the chest
B.Placing the patient in a supine position to aid venous return to the heart
C.Increasing the IV rate to increase the effective circulating volume
D.Applying rotating tourniquets

9.
Serum osmolality changes represent total body water changes provided that:
A.No solute is lost from the body
B.Only electrolytes are lost from the body
C.Cell membranes are impermeable to water
D.The serum osmolality is corrected for the urea concentration

10.
What is the estimated serum osmolality in a patient with a serum Na+ concentration of 140 mEq/L and serum glucose of 100 mg/dl?
A.280 mOsm/kg
B.140 mOsm/kg
C.100 mOsm/kg
D.240 mOsm/kg

11.
The osmolality of urine in a person with normal renal function:
A.Is only lowered to 100 mOsm/kg in water diuresis
B.May be lowered to less than 30 mOsm/kg in water diuresis
C.Is raised only to 900 mOsm/kg in fluid volume deficit
D.Is iso-osmotic with the plasma in an isotonic fluid volume deficit
E.Is iso-osmotic with the plasma in water diuresis

12.
A 65-year-old man with a 40-year history of heavy cigarette smoking and a recent diagnosis of oat cell carcinoma of the lung is admitted to the hospital with a 2-week history of progressive lethargy and headaches. Physical assessment is within normal limits except for the lethargy, headaches, and diminished deep tendon reflexes. Serum laboratory values reveal the following: Na+, 105 mEq/L; Cl-, 72 mEq/L; K+, 4 mEq/L; HCO-3, 23 mEq/L; plasma osmolality, 222 mOsm/kg. Urine laboratory values include the following: urine Na+, 78 mEq/L; urine osmolality, 804 mOsm/kg; specific gravity, 1.029. The most likely cause of this patient's problem is:
A.Diabetes insipidus (ADH deficiency)
B.Isotonic ECF volume excess
C.SIADH (ectopic source)
D.Hyperaldosteronism
E.Compulsive water drinking (psychogenic polydipsia)

13.
The direct cause of the patient's neurologic symptoms in question #12 is:
A.Brain cell shrinkage
B.Increased levels of circulating ADH
C.Decreased serum Na+ concentration
D.Brain cell swelling and increased intracranial pressure

14.
Which of the following is the best treatment for the patient in question #12?
A.Water restriction alone
B.Isotonic saline alone
C.Hypotonic saline
D.Hypertonic saline and water restriction

15.
When hypertonic (3% to 5%) saline is injected IV, which of the following will occur?
A.Water will be drawn out of the cells to the ECF compartment
B.Water will shift from the ECF compartment to the ICF compartment
C.The Na+ pump will maintain equilibrium
D.Urine output will decrease

16.
Which of the following conditions associated with hyponatremia causes plasma hyperosmolality rather than hypoosmolality?
A.Acute renal failure
B.SIADH
C.Uncontrolled diabetes mellitus
D.Diuretic excess

17.
Some iatrogenic causes of hypernatremia include
A.High-protein enteral tube feedings with insufficient water intake
B.Insufficient fluid provided for confused older adults
C.Prolonged use of artificial ventilator
D.Therapeutic abortion with hypertonic saline entry into circulation
E.All of the above

18.
Hypokalemia is associated with all of the following conditions except:
A.Protracted vomiting or diarrhea
B.Cushing's syndrome
C.Administration of IV glucose and regular insulin to correct diabetic ketoacidosis (DKA)
D.Mineralocorticoid deficiency in Addison's disease
E.Metabolic acidosis

19.
Hypokalemia associated with protracted vomiting is caused by:
A.Loss of K+ in vomitus
B.Loss of K+ in the urine
C.Lowering of serum K+ because of a shift into the cells
D.All of the above

20.
The most frequent cause of hypokalemia is likely:
A.Licorice ingestion
B.Diuretic drugs
C.Mg++ depletion
D.Primary hyperaldosteronism

21.
Clinical manifestations of hypokalemia include all of the following except:
A.Fatigue and generalized muscle weakness
B.Serum K+ < 3.5 mEq/L
C. Tall, peaked T waves
D. Decreased bowel sounds
E. Paresthesias

22.
Which statement about hypokalemia is false?
A.Diuretics, digitalis, and hypokalemia are a particularly dangerous combination.
B.Hypokalemia can be diagnosed on the basis of clinical signs and symptoms alone.
C.The rate of K+ administration should not exceed 20 mEq/hr when it is added to an IV line to correct hypokalemia.
D.Ingestion of citrus fruits and juices should be encouraged in persons on long-term diuretic therapy.

23.
Hyperkalemia can be treated by all of the following procedures except:
A.IV calcium gluconate
B.IV glucose and insulin
C.IV sodium bicarbonate
D.Oral or rectal ion exchange resin (Kayexalate)
E.IV acidic solution

24.
Which of the following statements best describes normal Ca++ homeostasis?
A.The rate of Ca++ absorption from the gut is equal to the urinary excretion of Ca++.
B.The rate of Ca++ reabsorption from the bone is equal to the amount of serum calcitonin.
C.The rate of Ca++ reabsorption by the renal tubules is equal to the rate of HPO=4 reabsorption by the renal tubules.

25.
Body processes affected by the concentration of Ca++ ion include:
A.Contraction of cardiac and skeletal muscle
B.Permeability of the cell membrane to Na+ and K+
C.Release of neurotransmitters at synaptic junctions
D.Excitability of nerve tissue
E.All of the above

26.
All of the following statements concerning 1,25(OH)2D3 are true except:
A.It is the most metabolically active form of vitamin D.
B.It acts in concert with PTH to increase osteoclastic bone activity.
C.It increases the absorption of Ca++ and HPO=4 from the gut.
D.PTH stimulates its final hydroxylation in the liver.

27.
The major effect of calcitonin is to:
A.Stimulate hydroxylation of cholecalciferol in the liver
B.Inhibit PTH secretion by the parathyroid glands
C.Inhibit osteoclastic bone activity
D.Stimulate hydroxylation of 25-cholecalciferol in the kidney

28.
Direct effects of PTH secretion on target organs include all of the following except:
A.Increased osteoclastic bone resorption of Ca++ and HPO=4
B.Increased renal tubular Ca++ reabsorption
C.Increased renal tubular HPO=4 reabsorption
D.Increased serum Ca++

29.
Which of the following forms of Ca++ is physiologically active (i.e., plays a role in muscle contraction, nerve conduction, and blood coagulation)?
A.Ionized Ca++
B.Calcium bound to albumin
C.Calcium bound to globulin
D.Calcium complexed with HPO=4

30.
To accurately assess the total serum calcium concentration in the laboratory report, the examiner must correlate the measurement with:
A.Serum Na+ level
B.Serum Cl- level
C.Serum albumin level
D.Serum K+ level

31.
The most common cause of hypoparathyroidism and hypocalcemia is:
A.Idiopathic
B.End-organ resistance
C.Surgical removal of the parathyroids
D.Postradiation therapy

32.
A postoperative complication that results from sudden increased skeletal absorption of Ca++ and HPO=4 from the blood is called:
A.Hungry bone syndrome
B.Hypercalcemic crisis
C.Thyroid crisis
D.Acromegaly

33.
Signs and symptoms of hypocalcemia are more likely to be manifested under conditions of:
A.Metabolic acidosis
B.Metabolic alkalosis
C.ECF volume deficit
D.Hyperphosphatemia

34.
To check for Trousseau's sign (indicating latent tetany), a blood pressure cuff is applied to the arm and inflated above systolic pressure for 3 to 5 minutes. A positive response would be:
A.Paresthesias of the fingers
B.Bounding pulses in the wrist following removal of the cuff
C.Spasm of the wrist and finger muscles
D.Hyperemia of the hand

35.
Spasm of the facial muscles induced by tapping the facial nerve in front of the ear (indicating latent tetany) is known as:
A.Chvostek's sign
B.Temporomandibular sign
C.Homans' sign
D.Brudzinski's sign

36.
The most common cause of hypercalcemia is:
A.Malignancies
B.Primary hyperparathyroidism
C.Vitamin D intoxication
D.Adrenal insufficiency

37.
Factors important in the development of humoral hypercalcemia of malignancy include all of the following except:
A.Transforming growth factors such as TGF-alpha
B.Parathyroid hormone-related peptide (PTHrP)
C.Lymphotoxin
D.Osteoclast deactivating factors
E.Interleukin-1

38.
ECG changes characteristic of hypercalcemia are:
A.Shortened PR interval
B.Shortened QT interval
C.Prolonged QT interval
D.Sinus tachycardia

39.
The treatment of hypercalcemia requires adequate:
A.Vitamin D intake
B.Treatment with thiazide diuretics
C.Protein intake
D.Hydration with saline followed by giving loop diuretics

40.
Asymptomatic patients with malignancy-related hypercalcemia (< 12 mg/dl) who are receiving antineoplastic treatment may only require:
A. Increased oral fluid intake
B. Restriction of dietary calcium
C. Limitation of weight-bearing activities
D. Liberal use of sedatives to ensure a good night's rest

41.
Gallium nitrate, used in the treatment of malignancy-related hypercalcemia, exerts a hypocalcemic effect by:
A.Stimulating an antitumor response
B.Reducing renal Na+ excretion
C.Blocking PTH-induced bone resorption of calcium
D.Enhancing the action of prostaglandin-synthesis inhibitors

42.
The most common cause contributing to hypomagnesemia is:
A.Alcohol abuse
B.Vitamin D intoxication
C.Administration of cisplatin
D.Hyperparathyroidism

43.
The effect of hypomagnesemia on the neuromuscular system is:
A.Decreased excitability
B.Increased excitability
C.Significant paralysis
D.Release of ATP from cells

44.
The most common cause of hypermagnesemia is:
A.Ingestion of magnesium-containing drugs by a patient with renal insufficiency or failure
B.Diabetic ketoacidosis (DKA)
C.Adrenal insufficiency
D.Hemodialysis using untreated (hard) water

45.
Which of the following drugs should the nurse have available for emergency use when Mg++ is administered IV?
A.Digoxin
B.Lidocaine
C.Potassium chloride
D.Calcium gluconate

46.
A 35-year-old male alcoholic was brought to the hospital in a comatose state after being discovered in an alley behind a tavern. The patient's skull was fractured. An indwelling catheter inserted into his bladder revealed a urine output of 175 ml/hr. Serum laboratory tests revealed the following: Na+, 170 mEq/L; Cl-, 132 mEq/L; K+, 4.0 mEq/L; serum glucose, 80 mg/dl; plasma osmolality, 345 mOsm/kg. The urine osmolality was 100 mOsm/kg. After administration of the vasopressin test, the urine output decreased to 90 ml/hr, and the osmolality increased to 270 mOsm/kg. His vital signs included the following: blood pressure 120/84 mm Hg; oral temperature, 99.6° F; pulse, 90 beats/min; respirations, 20 breaths/min. The probable cause of this patient's problem is:
A.Central diabetes insipidus
B.Nephrogenic diabetes insipidus
C.Osmotic diuresis
D.SIADH

47.
Which of the following statements are correct regarding the treatment of the fluid and electrolyte imbalance of the patient in question #46? (More than one answer may be correct.)
A.The primary goal is to lower the serum Na+ gradually to avoid causing cerebral edema.
B.A hypotonic IV solution (D5W or D5-0.2% NaCl) should be given.
C.Water restriction is the treatment of choice to decrease polyuria.
D.Chronic treatment consists of administering exogenous ADH.

48.
Third-space fluid loss: (More than one answer may be correct.)
A.Is manifested by rapid decrease in body weight
B.Is the accumulation of fluid in a non-ECF or non-ICF compartment, which is not easily exchangeable with the ECF
C.May reduce the effective circulating blood volume
D.Represents a distributional loss of fluids from the ECF

49.
Which of the following test results indicate an isotonic fluid volume deficit caused by extrarenal losses? (More than one answer may be correct.)
A.Serum Na+ 140 mEq/L
B.Hematocrit 55%
C.Urine specific gravity 1.038 (or 1200 mOsm/kg)
D.Urine Na+ < name="Q_080B04F036664FB8B7071DAE8D222F6C">50.

50.
Somatic compensatory responses to the rapid loss of a large amount of body fluid (e.g., sequestration in intestinal obstruction, bleeding) include: (More than one answer may be correct.)
A.Sympathetic activation and peripheral vasoconstriction
B.Diminished renal perfusion
C.Stimulation of the ADH mechanism, causing thirst and increased renal water reabsorption
D.Activation of the renin-angiotensin-aldosterone mechanism, causing increased renal Na+ (and water) reabsorption
E.Increased heart rate and contractility to restore cardiac output

51.
Which of the following situations presents a danger of circulatory overload (hypervolemia)? (More than one answer may be correct.)
A.Administration of a hypertonic IV solution
B.Congestive heart failure
C.Acute renal failure
D.Pyrexia lasting 4 days

52.
SIADH may be associated with: (More than one answer may be correct.)
A.Massive edema
B.CNS lesions and injuries
C.Postoperative conditions: cardiac surgery
D.Administration of oxytocin for labor induction
E.Administration of oral hypoglycemic agents

53.
Some causes of hyperkalemia include: (More than one answer may be correct.)
A.Poor venipuncture technique
B.Acute and chronic renal failure
C.Ingestion of salt substitutes in a person with renal insufficiency
D.Aldosterone deficiency
E.Tissue damage (e.g., surgery, burns)

54.
ECG changes suggesting hyperkalemia include: (More than one answer may be correct.)
A.High, peaked T waves
B.Prolonged PR interval
C.Depressed ST segment
D.Prolonged QRS intervals

55.
Hyperkalemia that reaches critical levels (> 7 to 8 mEq/L) presents a distinct danger of: (More than one answer may be correct.)
A.Cardiac dysrhythmias
B.Cardiac arrest
C.Hypertensive crisis
D.Hypovolemic shock
E.Increased cardiac contractility

56.
Hypocalcemia may be treated by giving: (More than one answer may be correct.)
A.Calcitonin
B.Calcium gluconate
C.Vitamin D
D.Diphosphonates
E.Plicamycin (Mithracin)

57.
In primary hyperparathyroidism: (More than one answer may be correct.)
A.Serum levels of PTH are always greater than it is in patients with hypercalcemia caused by vitamin D3 intoxication
B.An adenoma of one or more of the parathyroid glands is often the cause of the PTH hypersecretion
C.A generalized loss of bone mineralization may be evident on x-ray examination

58.
Which of the following signs or symptoms would the nurse most likely observe when assessing for hypophosphatemia? (More than one answer may be correct.)
A.Irritability, apprehension
B.Paresthesias
C.Diarrhea
D.Hypertension