Fluid & Electrolyte Mastery Quiz
Test your knowledge of nursing fundamentals
Score: 0/100
Question 1/100
Category 1: Fluid Compartments & Homeostasis
1. What percentage of the adult body is composed of water?
Answer: 60%
Explanation: In a healthy adult, about 60% of total body weight is water.
2. The majority of body fluid is located in which compartment?
Answer: Intracellular
Explanation: Approximately two-thirds of body water is located inside the cells, in the intracellular space.
3. Which hormone regulates water reabsorption in the kidneys?
Answer: ADH (Antidiuretic hormone)
Explanation: ADH acts on the kidneys to promote water reabsorption and maintain fluid balance.
4. Which pressure pulls fluid into capillaries from interstitial space?
Answer: Oncotic pressure
Explanation: Oncotic pressure, caused by plasma proteins, pulls water into the circulatory system.
5. Which electrolyte has the highest concentration in the intracellular fluid?
Answer: Potassium
Explanation: Potassium is the major cation in intracellular fluid and essential for cell function.
6. What mechanism is responsible for movement of water between compartments?
Answer: Osmosis
Explanation: Osmosis moves water from areas of low solute concentration to high solute concentration across membranes.
7. Aldosterone primarily affects which electrolyte balance?
Answer: Sodium
Explanation: Aldosterone increases sodium reabsorption and potassium excretion in the renal tubules.
8. The thirst mechanism is primarily controlled by:
Answer: Hypothalamus
Explanation: The hypothalamus detects increased osmolality and triggers thirst to restore fluid balance.
9. Which of the following is a transcellular fluid?
Answer: Synovial fluid
Explanation: Transcellular fluids include synovial, cerebrospinal, and pleural fluids, separate from interstitial or plasma compartments.
10. Which fluid compartment is plasma a part of?
Answer: Intravascular
Explanation: Plasma is the fluid portion of blood found within the intravascular space.
Category 2: Edema and Fluid Movement
11. What is edema?
Answer: Excess fluid in the interstitial space
Explanation: Edema is caused by accumulation of fluid in the interstitial tissue spaces.
12. Which of the following contributes to edema formation?
Answer: Increased capillary hydrostatic pressure
Explanation: Edema occurs when hydrostatic pressure pushes fluid out of capillaries into the interstitial space.
13. Which condition commonly causes edema due to low oncotic pressure?
Answer: Liver failure
Explanation: Liver failure reduces albumin production, lowering plasma oncotic pressure and causing edema.
14. What type of edema is seen in heart failure?
Answer: Pitting edema
Explanation: Right-sided heart failure leads to increased venous pressure and pitting edema in dependent areas.
15. What is a key characteristic of non-pitting edema?
Answer: Often associated with lymphatic obstruction
Explanation: Non-pitting edema occurs when lymphatic drainage is impaired and does not indent when pressed.
16. Which electrolyte is most involved in fluid shift and edema?
Answer: Sodium
Explanation: Sodium attracts water, and its retention causes fluid accumulation in extracellular compartments.
17. Which of the following reduces edema?
Answer: Diuretics
Explanation: Diuretics increase fluid excretion, helping to reduce fluid accumulation in the tissues.
18. Which type of fluid shift occurs in burns?
Answer: Intravascular to interstitial
Explanation: Burn injuries increase capillary permeability, causing fluid to leak into interstitial spaces.
19. Which plasma protein helps maintain oncotic pressure?
Answer: Albumin
Explanation: Albumin is the most abundant plasma protein that pulls fluid into the bloodstream via oncotic pressure.
20. A decrease in which factor will worsen edema?
Answer: Plasma protein level
Explanation: Low plasma proteins like albumin reduce oncotic pressure, promoting fluid shift into interstitial spaces.
Category 3: Fluid Volume Deficit and Excess
21. Which of the following is a sign of fluid volume deficit?
Answer: Tachycardia
Explanation: Tachycardia is a compensatory response to hypovolemia to maintain blood pressure and perfusion.
22. Which condition most commonly leads to fluid volume excess?
Answer: Heart failure
Explanation: Heart failure causes fluid retention due to poor cardiac output and activation of the RAAS system.
23. Which laboratory value is likely increased in dehydration?
Answer: Hematocrit
Explanation: Hemoconcentration during dehydration leads to increased hematocrit and hemoglobin levels.
24. What is the best indicator of fluid volume status?
Answer: Body weight
Explanation: Daily weight changes are the most accurate, non-invasive measure of fluid gain or loss.
25. Which symptom indicates hypovolemia?
Answer: Postural hypotension
Explanation: Postural hypotension is a drop in BP when standing, often seen in volume depletion.
26. Which hormone helps conserve water in hypovolemia?
Answer: ADH
Explanation: Antidiuretic hormone increases water reabsorption in the kidneys during hypovolemia.
27. Which of the following is NOT a symptom of fluid overload?
Answer: Dry mucous membranes
Explanation: Dry mucous membranes suggest dehydration, not fluid overload.
28. Fluid volume excess can cause which complication?
Answer: Pulmonary edema
Explanation: Excess fluid can accumulate in the lungs, leading to pulmonary edema and respiratory distress.
29. What is the treatment for severe hypovolemia?
Answer: IV fluid replacement
Explanation: Rapid IV fluid replacement restores circulating volume in hypovolemia.
30. Which lab finding supports diagnosis of fluid overload?
Answer: Decreased BUN
Explanation: Hemodilution in fluid overload may lower BUN and hematocrit values.
Category 4: Sodium Imbalance
31. What is the normal serum sodium level?
Answer: 135–145 mEq/L
Explanation: Normal sodium levels range from 135 to 145 mEq/L and are vital for nerve and muscle function.
32. What is a major cause of hyponatremia?
Answer: Diuretic use
Explanation: Diuretics can increase sodium loss in urine, leading to hyponatremia.
33. Which symptom is most commonly associated with hyponatremia?
Answer: Confusion
Explanation: Low sodium affects brain function, causing confusion, lethargy, and seizures.
34. What is the most dangerous complication of severe hyponatremia?
Answer: Cerebral edema
Explanation: Severe hyponatremia can cause brain cells to swell, leading to cerebral edema and herniation.
35. What is a cause of hypernatremia?
Answer: Diabetes insipidus
Explanation: Diabetes insipidus causes excessive water loss, leading to concentrated sodium in the blood.
36. Which symptom is consistent with hypernatremia?
Answer: Thirst
Explanation: Thirst is an early and primary symptom of hypernatremia as the body tries to correct water imbalance.
37. What is the safest treatment for mild hypernatremia?
Answer: Gradual oral water intake
Explanation: Gradual replacement of free water prevents cerebral edema caused by too-rapid correction.
38. Which hormone is primarily responsible for sodium retention?
Answer: Aldosterone
Explanation: Aldosterone promotes sodium retention in the distal renal tubules to maintain fluid balance.
39. Which of the following can cause dilutional hyponatremia?
Answer: Syndrome of inappropriate ADH (SIADH)
Explanation: SIADH causes water retention, diluting serum sodium concentration.
40. Which complication can occur if hypernatremia is corrected too rapidly?
Answer: Cerebral edema
Explanation: Rapid correction of hypernatremia allows water to rush into brain cells, causing swelling and potentially fatal cerebral edema.
Category 5: Potassium Imbalance
41. What is the normal serum potassium range?
Answer: 3.5–5.0 mEq/L
Explanation: Potassium is essential for neuromuscular function and cardiac rhythm regulation.
42. Which condition is a common cause of hypokalemia?
Answer: Diarrhea
Explanation: Potassium is lost through the GI tract in cases of diarrhea, leading to hypokalemia.
43. Which symptom is associated with hypokalemia?
Answer: Muscle weakness
Explanation: Hypokalemia impairs muscle function, often leading to generalized weakness and fatigue.
44. What is the ECG change seen in hypokalemia?
Answer: U waves
Explanation: U waves are an ECG hallmark of hypokalemia, reflecting delayed ventricular repolarization.
45. What is a major risk of hypokalemia?
Answer: Cardiac arrhythmias
Explanation: Hypokalemia alters cardiac conduction, increasing the risk for dangerous arrhythmias.
46. Which food is highest in potassium?
Answer: Banana
Explanation: Bananas are rich in potassium and often recommended to correct or prevent hypokalemia.
47. What is the danger of IV potassium given too quickly?
Answer: Cardiac arrest
Explanation: Rapid IV potassium can cause fatal cardiac arrhythmias or arrest; it must be diluted and infused slowly.
48. What is a key cause of hyperkalemia?
Answer: Renal failure
Explanation: The kidneys excrete potassium, so impaired function leads to accumulation and hyperkalemia.
49. What ECG change is typical in hyperkalemia?
Answer: Peaked T waves
Explanation: Peaked or tented T waves reflect early repolarization changes seen in hyperkalemia.
50. Which medication is used to lower potassium in emergencies?
Answer: All of the above
Explanation: Calcium gluconate protects the heart, furosemide increases excretion, and Kayexalate binds potassium in the gut.
Category 6: Calcium Imbalance
51. What is the normal serum calcium range?
Answer: 8.5–10.5 mg/dL
Explanation: Normal calcium is tightly regulated and essential for muscle contraction, blood clotting, and nerve transmission.
52. What is a common cause of hypocalcemia?
Answer: Vitamin D deficiency
Explanation: Vitamin D is needed for calcium absorption in the gut; its deficiency leads to hypocalcemia.
53. Which symptom is characteristic of hypocalcemia?
Answer: Tetany
Explanation: Low calcium levels increase neuromuscular excitability, causing spasms and tetany.
54. Which sign indicates hypocalcemia?
Answer: Trousseau's sign
Explanation: Trousseau's sign (carpal spasm with BP cuff inflation) is a classic indicator of hypocalcemia.
55. What is a typical ECG finding in hypocalcemia?
Answer: Prolonged QT interval
Explanation: Hypocalcemia lengthens the ST segment and QT interval, increasing risk of arrhythmia.
56. What is the main hormone that increases serum calcium levels?
Answer: Parathyroid hormone (PTH)
Explanation: PTH increases calcium by stimulating bone resorption, kidney reabsorption, and activating vitamin D.
57. What is a common cause of hypercalcemia?
Answer: Hyperparathyroidism
Explanation: Overproduction of PTH increases calcium levels through bone resorption and kidney reabsorption.
58. Which symptom is associated with hypercalcemia?
Answer: Bone pain
Explanation: High calcium levels from bone resorption may cause weakness and bone pain.
59. What ECG finding is typical in hypercalcemia?
Answer: Shortened QT interval
Explanation: Hypercalcemia shortens the repolarization phase, leading to a shorter QT interval.
60. Which intervention is appropriate for severe hypercalcemia?
Answer: IV saline with loop diuretics
Explanation: Hydration with saline promotes calcium excretion; loop diuretics (not thiazides) enhance renal loss.
Category 7: Magnesium Imbalance
61. What is the normal range of serum magnesium?
Answer: 1.5–2.5 mg/dL
Explanation: Normal serum magnesium levels are 1.5–2.5 mg/dL and are essential for enzyme function and neuromuscular activity.
62. Which condition commonly causes hypomagnesemia?
Answer: Chronic alcoholism
Explanation: Chronic alcohol use leads to poor dietary intake and increased renal magnesium loss.
63. Which symptom is associated with hypomagnesemia?
Answer: Muscle tremors
Explanation: Hypomagnesemia increases neuromuscular excitability, causing tremors, twitching, and seizures.
64. What ECG change is seen with hypomagnesemia?
Answer: Prolonged QT interval
Explanation: Hypomagnesemia can prolong the QT interval, increasing the risk of arrhythmias like torsades de pointes.
65. What is a primary cause of hypermagnesemia?
Answer: Renal failure
Explanation: Impaired renal function reduces magnesium excretion, leading to accumulation and hypermagnesemia.
66. Which symptom is associated with hypermagnesemia?
Answer: Lethargy
Explanation: High magnesium levels depress the nervous system, causing lethargy, weakness, and respiratory depression.
67. What is a treatment for hypermagnesemia?
Answer: Calcium gluconate
Explanation: Calcium gluconate antagonizes magnesium's effects, stabilizing cardiac and neuromuscular function.
68. Which ECG change is seen in hypermagnesemia?
Answer: Prolonged PR interval
Explanation: Hypermagnesemia slows cardiac conduction, often causing a prolonged PR interval and bradycardia.
69. Which medication can contribute to hypomagnesemia?
Answer: Loop diuretics
Explanation: Loop diuretics increase magnesium excretion in urine, contributing to hypomagnesemia.
70. Which food is a good source of magnesium?
Answer: Spinach
Explanation: Leafy greens like spinach are rich in magnesium, aiding in correcting deficiencies.
Category 8: Phosphate Imbalance
71. What is the normal serum phosphate range?
Answer: 2.5–4.5 mg/dL
Explanation: Phosphate is essential for bone health, energy production, and acid-base balance.
72. What is a common cause of hypophosphatemia?
Answer: Alcoholism
Explanation: Chronic alcoholism causes poor intake, malabsorption, and increased renal loss of phosphate.
73. Which symptom is associated with hypophosphatemia?
Answer: Muscle weakness
Explanation: Low phosphate impairs ATP production, leading to muscle weakness and fatigue.
74. What is a cause of hyperphosphatemia?
Answer: Renal failure
Explanation: Impaired kidneys cannot excrete phosphate, leading to accumulation in the blood.
75. Which treatment is used for hyperphosphatemia?
Answer: Phosphate binders
Explanation: Phosphate binders reduce absorption of dietary phosphate in the gut, lowering serum levels.
76. Which hormone decreases serum phosphate levels?
Answer: Parathyroid hormone (PTH)
Explanation: PTH increases renal phosphate excretion, lowering serum phosphate levels.
77. Which condition is associated with hyperphosphatemia?
Answer: Hypoparathyroidism
Explanation: Low PTH reduces phosphate excretion, causing serum phosphate to rise.
78. What is a complication of severe hypophosphatemia?
Answer: Cardiac arrhythmias
Explanation: Severe hypophosphatemia impairs cardiac function, increasing arrhythmia risk due to low ATP.
79. Which food is high in phosphate?
Answer: Dairy products
Explanation: Dairy products like milk and cheese are rich in phosphate, aiding in deficiency correction.
80. What is a risk of rapid phosphate correction?
Answer: Hypocalcemia
Explanation: Rapid phosphate infusion can bind calcium, causing hypocalcemia and related complications.
Category 9: Acid-Base Balance
81. What is the normal arterial blood pH range?
Answer: 7.35–7.45
Explanation: Normal arterial pH is tightly regulated to maintain homeostasis and support metabolic functions.
82. Which condition causes metabolic acidosis?
Answer: Diabetic ketoacidosis
Explanation: DKA produces excess ketones, lowering blood pH and causing metabolic acidosis.
83. What is a compensatory mechanism for metabolic acidosis?
Answer: Hyperventilation
Explanation: The lungs compensate by exhaling more CO2, reducing carbonic acid and raising pH.
84. Which condition leads to respiratory acidosis?
Answer: COPD
Explanation: Chronic obstructive pulmonary disease causes CO2 retention, increasing carbonic acid and lowering pH.
85. What is a hallmark sign of respiratory acidosis?
Answer: Hypoventilation
Explanation: Hypoventilation reduces CO2 exhalation, leading to acid accumulation and respiratory acidosis.
86. Which condition causes metabolic alkalosis?
Answer: Prolonged vomiting
Explanation: Vomiting causes loss of HCl, increasing blood pH and leading to metabolic alkalosis.
87. What compensates for respiratory alkalosis?
Answer: Increased bicarbonate excretion
Explanation: Kidneys excrete bicarbonate to lower pH in response to low CO2 from hyperventilation.
88. Which lab value indicates metabolic acidosis?
Answer: Low pH, low bicarbonate
Explanation: Metabolic acidosis is marked by low pH and reduced bicarbonate due to acid accumulation.
89. Which condition causes respiratory alkalosis?
Answer: Anxiety-induced hyperventilation
Explanation: Hyperventilation reduces CO2, decreasing carbonic acid and raising pH.
90. What is a treatment for metabolic alkalosis?
Answer: Ammonium chloride
Explanation: Ammonium chloride provides acid to correct the excess base in metabolic alkalosis.
Category 10: Clinical Applications
91. Which IV fluid is isotonic and used for fluid replacement?
Answer: 0.9% NaCl
Explanation: Normal saline (0.9% NaCl) is isotonic, ideal for restoring intravascular volume without shifting fluids.
92. Which electrolyte imbalance is a risk with rapid IV saline infusion?
Answer: Hypernatremia
Explanation: Rapid infusion of 0.9% NaCl can increase sodium levels, risking hypernatremia if not monitored.
93. Which assessment is critical before administering IV potassium?
Answer: Urine output
Explanation: Adequate renal function (urine output) is essential to prevent hyperkalemia during potassium infusion.
94. Which condition requires careful fluid restriction?
Answer: SIADH
Explanation: SIADH causes water retention, so fluid restriction is used to prevent dilutional hyponatremia.
95. What is a priority nursing action for a patient with hyperkalemia?
Answer: Monitor ECG
Explanation: Hyperkalemia can cause life-threatening arrhythmias, making ECG monitoring critical.
96. What is the treatment for severe hyponatremia?
Answer: 3% NaCl
Explanation: Hypertonic 3% NaCl is used cautiously to correct severe hyponatremia, preventing rapid fluid shifts.
97. Which electrolyte imbalance is a risk with prolonged nasogastric suction?
Answer: Hyponatremia
Explanation: NG suction removes sodium-rich gastric fluid, increasing the risk of hyponatremia.
98. Which symptom indicates severe hypocalcemia in a postoperative patient?
Answer: Laryngeal spasm
Explanation: Severe hypocalcemia can cause life-threatening laryngeal spasms.
99. Which lab value should be monitored during diuretic therapy?
Answer: All of the above
Explanation: Diuretics can alter sodium, potassium, and calcium levels, requiring comprehensive monitoring.
100. What is the priority action for a patient with suspected fluid overload?
Answer: Assess lung sounds
Explanation: Lung sounds can reveal crackles indicating pulmonary edema, a critical complication of fluid overload.
