Fluids, Electrolytes, and Acid-base Balance Practice Questions

95 multiple-choice questions on Fluids, electrolytes, and acid-base balance for paramedic and EMT students, from Chapter 9 (Pathophysiology). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

95 practice questions

1. Edema results from:

   1. A. Increased cellular metabolic activity
   2. B. Low serum sodium from water loss
   3. C. High plasma albumin pulling fluid into tissue
   4. D. Pressure imbalance or leaky capillaries
   Show answer

   Answer: D. Pressure imbalance or leaky capillaries

   An imbalance of hydrostatic and oncotic pressures, or increased capillary permeability, causes edema. Heart failure, liver disease, and sepsis all produce it by different routes. Albumin holds fluid inside the vessels, so a low level, not a high one, favors edema.

2. Low plasma albumin causes edema because it:

   1. A. Increases sodium retention by kidneys
   2. B. Blocks lymphatic drainage of tissue
   3. C. Raises capillary hydrostatic pressure
   4. D. Lowers plasma oncotic pressure
   Show answer

   Answer: D. Lowers plasma oncotic pressure

   With lower oncotic pressure, water is not held in the vessels. Malnutrition and liver failure both lower albumin.

3. Dehydration in an adult commonly presents with:

   1. A. Bounding pulses and moist membranes
   2. B. Tachycardia and dry mucous membranes
   3. C. Hypertension and distended neck veins
   4. D. Bradycardia and warm, flushed skin
   Show answer

   Answer: B. Tachycardia and dry mucous membranes

   Expect tachycardia, dry mucous membranes, poor skin turgor, and reduced urine output. Orthostatic changes may appear before frank hypotension.

4. Hyponatremia can cause:

   1. A. Cardiac dysrhythmias as its only effect
   2. B. Muscle cramps but no neurologic signs
   3. C. Confusion, weakness, and seizures
   4. D. Thirst and shrinkage of brain cells
   Show answer

   Answer: C. Confusion, weakness, and seizures

   Water shifts into brain cells. It can result from excessive water intake or certain medications.

5. Hyperkalemia is dangerous mainly because it:

   1. A. Causes metabolic alkalosis
   2. B. Paralyzes the respiratory drive
   3. C. Disrupts cardiac conduction
   4. D. Causes a hypertensive crisis
   Show answer

   Answer: C. Disrupts cardiac conduction

   It can cause lethal dysrhythmias. Renal failure and crush injury are common causes. Hyperkalemia is linked to acidosis, which shifts potassium out of cells, not to alkalosis.

6. Hypokalemia may result from:

   1. A. Acidosis and potassium supplements
   2. B. Crush injury and rhabdomyolysis
   3. C. Renal failure and missed dialysis
   4. D. Vomiting, diarrhea, and diuretics
   Show answer

   Answer: D. Vomiting, diarrhea, and diuretics

   It also causes weakness and dysrhythmias.

7. Calcium is essential for:

   1. A. Oxygen transport by hemoglobin
   2. B. Glucose transport into muscle cells
   3. C. Muscle contraction and clotting
   4. D. Acid-base buffering in plasma
   Show answer

   Answer: C. Muscle contraction and clotting

   Calcium is needed for muscle contraction, nerve conduction, and coagulation. Low ionized calcium impairs cardiac contractility.

8. Respiratory acidosis results from:

   1. A. Loss of gastric acid from vomiting
   2. B. Retained CO2 from hypoventilation
   3. C. Hyperventilation from anxiety or pain
   4. D. Bicarbonate loss from severe diarrhea
   Show answer

   Answer: B. Retained CO2 from hypoventilation

   Inadequate ventilation retains carbon dioxide. Any cause of hypoventilation produces it.

9. Respiratory alkalosis results from:

   1. A. Hyperventilation lowering CO2
   2. B. Hypoventilation retaining CO2
   3. C. Renal failure retaining acid
   4. D. Bicarbonate loss in diarrhea
   Show answer

   Answer: A. Hyperventilation lowering CO2

   Anxiety, pain, and early sepsis can all cause it.

10. Metabolic acidosis may be caused by:

    1. A. Hyperventilation from pain or anxiety
    2. B. Prolonged vomiting of stomach acid
    3. C. Shock, DKA, renal failure, or diarrhea
    4. D. Hypoventilation from opioid overdose
    Show answer

    Answer: C. Shock, DKA, renal failure, or diarrhea

    Lactic acid in shock, ketoacidosis, renal failure, and bicarbonate loss in severe diarrhea all cause it. The lungs compensate by increasing ventilation.

11. Metabolic alkalosis is commonly caused by:

    1. A. Renal failure with acid retention
    2. B. Prolonged vomiting or antacid excess
    3. C. Shock with lactic acid buildup
    4. D. Severe diarrhea with bicarbonate loss
    Show answer

    Answer: B. Prolonged vomiting or antacid excess

    Loss of gastric acid leaves the blood relatively alkaline.

12. Kussmaul respirations represent:

    1. A. Fatigue signaling respiratory failure
    2. B. Compensation for metabolic acidosis
    3. C. Brainstem injury after head trauma
    4. D. Partial upper airway obstruction
    Show answer

    Answer: B. Compensation for metabolic acidosis

    They are deep, rapid breaths compensating for metabolic acidosis, classically seen in diabetic ketoacidosis.

13. Respiratory compensation for a metabolic problem occurs:

    1. A. Only after the kidneys respond
    2. B. Within minutes
    3. C. Within seconds
    4. D. Over several days
    Show answer

    Answer: B. Within minutes

    Renal compensation takes hours to days.

14. The body's response to acidosis includes:

    1. A. Shift of potassium into the cells
    2. B. Renal retention of hydrogen ions
    3. C. Slower breathing to conserve bicarbonate
    4. D. Increased ventilation and H+ excretion
    Show answer

    Answer: D. Increased ventilation and H+ excretion

    Ventilation rises to blow off carbon dioxide and the kidneys excrete hydrogen ions. Acidosis also shifts potassium out of cells, raising serum potassium.

15. An isotonic fluid such as normal saline given IV will:

    1. A. Draw water out of cells, shrinking them
    2. B. Remain mostly in the extracellular space
    3. C. Shift largely into the intracellular space
    4. D. Supply calories along with volume
    Show answer

    Answer: B. Remain mostly in the extracellular space

    It expands intravascular volume, though much of it redistributes into the interstitial space over time.

16. Third spacing refers to:

    1. A. Fluid trapped outside the circulation
    2. B. Fluid retained within the blood vessels
    3. C. Fluid moving into the intracellular space
    4. D. Insensible fluid loss through the skin
    Show answer

    Answer: A. Fluid trapped outside the circulation

    Fluid shifts into a space such as the abdomen or interstitium where it is unavailable to the circulation. The patient can be hypovolemic while total body water is high.

17. Total body water is approximately what fraction of body weight in an average adult male?

    1. A. 20 percent
    2. B. 60 percent
    3. C. 40 percent
    4. D. 80 percent
    Show answer

    Answer: B. 60 percent

    Lower in women and older adults because of fat.

18. Intracellular fluid makes up approximately:

    1. A. Half of body water
    2. B. Two-thirds of body water
    3. C. All body water
    4. D. One-third of body water
    Show answer

    Answer: B. Two-thirds of body water

    About 40 percent of body weight.

19. Extracellular fluid includes:

    1. A. Lymph and cerebrospinal fluid only
    2. B. Interstitial fluid and plasma
    3. C. Plasma and intracellular fluid
    4. D. Intracellular and interstitial fluid
    Show answer

    Answer: B. Interstitial fluid and plasma

    It includes interstitial fluid, plasma, and transcellular fluids, about 20 percent of body weight.

20. Transcellular fluid includes:

    1. A. Plasma and lymph in the vessels
    2. B. Water inside red cells
    3. C. Cerebrospinal and pleural fluid
    4. D. Interstitial fluid around cells
    Show answer

    Answer: C. Cerebrospinal and pleural fluid

    Cerebrospinal, synovial, pleural, and peritoneal fluids are transcellular. Small in volume but important.

21. Water moves between compartments primarily by:

    1. A. Active transport by pumps
    2. B. Capillary filtration alone
    3. C. Facilitated diffusion
    4. D. Osmosis across membranes
    Show answer

    Answer: D. Osmosis across membranes

    Following solute concentration.

22. Tonicity refers to:

    1. A. The pressure exerted by plasma proteins
    2. B. The hydrogen ion concentration
    3. C. The effect of a solution on cell volume
    4. D. The total solute content of a solution
    Show answer

    Answer: C. The effect of a solution on cell volume

    It depends on solutes that cannot cross the membrane.

23. Starling forces govern:

    1. A. Hormone release from the pituitary
    2. B. Ion movement across nerve membranes
    3. C. Oxygen diffusion across the alveoli
    4. D. Fluid movement across capillary walls
    Show answer

    Answer: D. Fluid movement across capillary walls

    Hydrostatic and oncotic pressures.

24. Capillary hydrostatic pressure is highest at the:

    1. A. Arterial end
    2. B. Lymphatic end
    3. C. Midpoint
    4. D. Venous end
    Show answer

    Answer: A. Arterial end

    Fluid filters out there.

25. Oncotic pressure pulls fluid back into the capillary at the:

    1. A. Venous end
    2. B. Midpoint
    3. C. Arterial end
    4. D. Lymphatic end
    Show answer

    Answer: A. Venous end

    Hydrostatic pressure has fallen there, so oncotic pressure draws fluid back. Reabsorption.

26. Lymphatics return:

    1. A. The entire filtered fluid volume
    2. B. The small excess not reabsorbed
    3. C. No fluid under normal conditions
    4. D. Escaped protein but no water
    Show answer

    Answer: B. The small excess not reabsorbed

    They return the small excess of filtered fluid not reabsorbed, about 3 liters daily.

27. Edema from increased hydrostatic pressure occurs in:

    1. A. Heart failure and venous clots
    2. B. Nephrotic protein loss
    3. C. Liver failure and malnutrition
    4. D. Burns and septic capillary leak
    Show answer

    Answer: A. Heart failure and venous clots

    Heart failure and venous obstruction raise hydrostatic pressure. Blood backs up.

28. Edema from decreased oncotic pressure occurs in:

    1. A. Lymph node removal after surgery
    2. B. Heart failure and fluid overload
    3. C. Liver failure and malnutrition
    4. D. Deep vein thrombosis in a leg
    Show answer

    Answer: C. Liver failure and malnutrition

    Liver failure, malnutrition, and nephrotic syndrome all lower albumin.

29. Edema from increased capillary permeability occurs in:

    1. A. Lymphatic obstruction from surgery
    2. B. Heart failure with venous congestion
    3. C. Burns, sepsis, and allergic reactions
    4. D. Malnutrition with low albumin
    Show answer

    Answer: C. Burns, sepsis, and allergic reactions

    Inflammation, burns, sepsis, and allergic reactions make capillaries leaky. Protein leaks out.

30. Edema from lymphatic obstruction occurs in:

    1. A. Right-sided heart failure
    2. B. Severe protein malnutrition
    3. C. After lymph node removal
    4. D. Septic capillary leak
    Show answer

    Answer: C. After lymph node removal

    It also occurs in parasitic infection. Lymphedema.

31. Pitting edema is assessed by:

    1. A. Measuring limb circumference with tape
    2. B. Comparing serial body weights
    3. C. Pressing in and watching for a dent
    4. D. Visual inspection of the swollen limb
    Show answer

    Answer: C. Pressing in and watching for a dent

    Press a finger into the tissue and see whether a depression remains. Graded 1 to 4.

32. Pulmonary edema impairs:

    1. A. Circulation
    2. B. Upper airway patency
    3. C. Hemoglobin's oxygen binding
    4. D. Gas exchange
    Show answer

    Answer: D. Gas exchange

    Fluid in the alveoli. The upper airway stays open, and hemoglobin binds oxygen normally; the problem is the fluid barrier at the alveoli.

33. Cerebral edema is dangerous because:

    1. A. It compresses the spinal cord first
    2. B. It blocks oxygen binding to hemoglobin
    3. C. It lowers blood volume dangerously
    4. D. The rigid skull lets pressure rise
    Show answer

    Answer: D. The rigid skull lets pressure rise

    The skull cannot expand, so pressure rises. Herniation can follow. Swelling pushes brain tissue toward the brainstem, not the spinal cord first, and it does not affect hemoglobin's ability to bind oxygen.

34. Dehydration can result from:

    1. A. Inadequate oral intake, not losses
    2. B. Sweating and fever but not bleeding
    3. C. GI losses but not urine or blood
    4. D. Intake deficits and multiple losses
    Show answer

    Answer: D. Intake deficits and multiple losses

    Causes include inadequate intake, vomiting, diarrhea, sweating, polyuria, and bleeding. Many routes of loss.

35. Isotonic dehydration involves loss of:

    1. A. More water than electrolytes
    2. B. Water and electrolytes in proportion
    3. C. Water alone, without electrolytes
    4. D. Electrolytes alone, without water
    Show answer

    Answer: B. Water and electrolytes in proportion

    Hemorrhage and vomiting.

36. Hypertonic dehydration involves:

    1. A. More water lost than solute
    2. B. Loss of plasma protein only
    3. C. Equal water and solute losses
    4. D. More solute lost than water
    Show answer

    Answer: A. More water lost than solute

    Losing more water than solute raises osmolarity. Diabetes insipidus or inadequate intake.

37. Hypotonic dehydration involves:

    1. A. More solute lost than water
    2. B. Equal water and solute losses
    3. C. Loss of plasma protein only
    4. D. More water lost than solute
    Show answer

    Answer: A. More solute lost than water

    Losing more solute than water lowers osmolarity, often when losses are replaced with plain water.

38. Signs of dehydration in infants include:

    1. A. Periorbital edema and puffy eyelids
    2. B. Sunken fontanelle and fewer wet diapers
    3. C. Bulging fontanelle and irritability
    4. D. Hypertension with a slow heart rate
    Show answer

    Answer: B. Sunken fontanelle and fewer wet diapers

    Decreased tears and dry mucous membranes also appear. Weight loss is the most accurate measure.

39. Signs of dehydration in older adults include:

    1. A. Bradycardia and warm, moist skin
    2. B. Confusion and orthostatic changes
    3. C. Hypertension and bounding pulses
    4. D. Peripheral edema and weight gain
    Show answer

    Answer: B. Confusion and orthostatic changes

    Look for confusion, orthostatic hypotension, and dry mucous membranes. Skin turgor is unreliable.

40. Fluid overload presents with:

    1. A. Flat neck veins and tachycardia
    2. B. Edema, crackles, and JVD
    3. C. Intense thirst and dark urine
    4. D. Dry mucosa and poor skin turgor
    Show answer

    Answer: B. Edema, crackles, and JVD

    Edema, crackles, JVD, and weight gain are typical. Heart and kidney failure are common causes.

41. Sodium's normal serum range is approximately:

    1. A. 150 to 160 mEq/L
    2. B. 95 to 105 mEq/L
    3. C. 115 to 125 mEq/L
    4. D. 135 to 145 mEq/L
    Show answer

    Answer: D. 135 to 145 mEq/L

    Tight regulation.

42. Hypernatremia symptoms include:

    1. A. Peripheral edema and weight gain
    2. B. Peaked T waves and bradycardia
    3. C. Thirst, confusion, and seizures
    4. D. Muscle cramps without confusion
    Show answer

    Answer: C. Thirst, confusion, and seizures

    Weakness also occurs. Brain cells shrink.

43. Rapid correction of hyponatremia can cause:

    1. A. Cerebral edema from water shift
    2. B. Acute renal tubular necrosis
    3. C. Rebound severe hypernatremia
    4. D. Osmotic demyelination syndrome
    Show answer

    Answer: D. Osmotic demyelination syndrome

    Correct slowly. Renal tubular necrosis results from ischemia or toxins, not from sodium correction.

44. Potassium's normal serum range is approximately:

    1. A. 1.5 to 2.5 mEq/L
    2. B. 5.5 to 6.5 mEq/L
    3. C. 3.5 to 5.0 mEq/L
    4. D. 2.5 to 3.5 mEq/L
    Show answer

    Answer: C. 3.5 to 5.0 mEq/L

    Narrow and critical.

45. ECG changes in hyperkalemia include:

    1. A. Prominent U waves and a long QT
    2. B. Peaked T waves and a widening QRS
    3. C. Flattened T waves and U waves
    4. D. ST elevation in contiguous leads
    Show answer

    Answer: B. Peaked T waves and a widening QRS

    Peaked T waves and a widening QRS progress to a sine wave as levels rise.

46. ECG changes in hypokalemia include:

    1. A. Peaked T waves and wide QRS
    2. B. Flattened T waves and U waves
    3. C. A sine-wave QRS-T pattern
    4. D. A shortened QT and tall T waves
    Show answer

    Answer: B. Flattened T waves and U waves

    Dysrhythmias follow.

47. Causes of hyperkalemia include:

    1. A. Loop diuretic use and vomiting
    2. B. Diarrhea and laxative abuse
    3. C. Alkalosis and insulin therapy
    4. D. Renal failure and crush injury
    Show answer

    Answer: D. Renal failure and crush injury

    Renal failure, crush injury, acidosis, and certain medications raise potassium. Potassium shifts out of cells in acidosis.

48. A patient taking furosemide has vomited for 3 days and now has muscle weakness, flattened T waves, and U waves. Which treatment will the hospital most likely need?

    1. A. Calcium gluconate
    2. B. Insulin with dextrose
    3. C. Sodium bicarbonate
    4. D. Potassium replacement
    Show answer

    Answer: D. Potassium replacement

    Loop diuretics and vomiting both waste potassium, and U waves with flat T waves are the ECG signs of hypokalemia, so potassium must be replaced. Calcium, insulin with dextrose, and bicarbonate are treatments for hyperkalemia and would make this worse or do nothing.

49. A patient with chronic kidney disease has a calcium of 6.8 mg/dL. Which finding would you expect?

    1. A. Constipation and kidney stones
    2. B. Carpopedal spasm and a prolonged QT
    3. C. Peaked T waves and a wide QRS
    4. D. U waves and flattened T waves
    Show answer

    Answer: B. Carpopedal spasm and a prolonged QT

    Calcium stabilizes nerve and muscle membranes. When it is low, they become irritable (tetany, carpopedal spasm), and repolarization lengthens (prolonged QT). Constipation and stones suggest hypercalcemia. Peaked T waves suggest hyperkalemia, and U waves suggest hypokalemia.

50. Hypocalcemia signs include:

    1. A. Kidney stones and bone pain
    2. B. Tetany and a prolonged QT
    3. C. Weakness and a shortened QT
    4. D. Constipation and abdominal pain
    Show answer

    Answer: B. Tetany and a prolonged QT

    Tetany, tingling, muscle spasms, and a prolonged QT occur. Chvostek and Trousseau signs.

51. Hypercalcemia signs include:

    1. A. Tetany and carpopedal spasm
    2. B. Prolonged QT and laryngospasm
    3. C. Perioral tingling and paresthesias
    4. D. Constipation and kidney stones
    Show answer

    Answer: D. Constipation and kidney stones

    Weakness, confusion, constipation, and kidney stones: stones, bones, groans, and psychiatric overtones.

52. Magnesium is important for:

    1. A. Oxygen transport in red blood cells
    2. B. Clotting factor activation only
    3. C. Bone mineral structure alone
    4. D. Enzyme function and cardiac rhythm
    Show answer

    Answer: D. Enzyme function and cardiac rhythm

    It supports enzyme function, neuromuscular activity, and cardiac rhythm stability. Low magnesium worsens hypokalemia.

53. Hypomagnesemia is associated with:

    1. A. Peaked T waves and bradycardia
    2. B. Hypertensive crisis and stroke
    3. C. Constipation and kidney stones
    4. D. Torsades and other dysrhythmias
    Show answer

    Answer: D. Torsades and other dysrhythmias

    It is common in alcoholism. Replace magnesium to control torsades.

54. Phosphate is important for:

    1. A. Bone mineralization only
    2. B. Clotting and muscle contraction
    3. C. Bone, ATP, and buffering
    4. D. Nerve conduction and clotting
    Show answer

    Answer: C. Bone, ATP, and buffering

    Phosphate is needed for bone, ATP production, and buffering. It moves opposite to calcium.

55. Chloride generally follows:

    1. A. Calcium
    2. B. Potassium
    3. C. Sodium
    4. D. Magnesium
    Show answer

    Answer: C. Sodium

    Maintaining electrical neutrality.

56. Bicarbonate's main role is:

    1. A. Clotting
    2. B. Buffering acid
    3. C. Oxygen transport
    4. D. Muscle contraction
    Show answer

    Answer: B. Buffering acid

    The main extracellular buffer.

57. The normal arterial pH range is:

    1. A. 7.25 to 7.35
    2. B. 7.45 to 7.55
    3. C. 7.35 to 7.45
    4. D. 7.00 to 7.20
    Show answer

    Answer: C. 7.35 to 7.45

    Life is compatible with roughly 6.8 to 7.8.

58. Normal PaCO2 is approximately:

    1. A. 25 to 30 mm Hg
    2. B. 50 to 60 mm Hg
    3. C. 60 to 70 mm Hg
    4. D. 35 to 45 mm Hg
    Show answer

    Answer: D. 35 to 45 mm Hg

    The respiratory component.

59. Normal serum bicarbonate is approximately:

    1. A. 22 to 26 mEq/L
    2. B. 30 to 35 mEq/L
    3. C. 12 to 16 mEq/L
    4. D. 40 to 45 mEq/L
    Show answer

    Answer: A. 22 to 26 mEq/L

    The metabolic component.

60. The three systems that regulate pH are:

    1. A. Lungs, skin, and intestines
    2. B. Kidneys, liver, and spleen
    3. C. Heart, lungs, and liver
    4. D. Buffers, lungs, and kidneys
    Show answer

    Answer: D. Buffers, lungs, and kidneys

    Chemical buffers, the respiratory system, and the renal system act fast, medium, and slow.

61. Chemical buffers act within:

    1. A. Days
    2. B. Minutes
    3. C. Seconds
    4. D. Hours
    Show answer

    Answer: C. Seconds

    Immediate but limited capacity.

62. A patient in DKA has a serum bicarbonate of 8 mEq/L. Within minutes, which compensation do you expect to see?

    1. A. Deep, rapid Kussmaul breathing
    2. B. Slow, shallow breathing
    3. C. Renal bicarbonate retention only, over days
    4. D. No compensation until treatment begins
    Show answer

    Answer: A. Deep, rapid Kussmaul breathing

    The respiratory system compensates for metabolic acidosis within minutes by blowing off CO2, which produces Kussmaul respirations. Slow breathing would worsen the acidosis. Renal compensation works over hours to days. Compensation starts without treatment.

63. The renal system compensates within:

    1. A. Several weeks
    2. B. Seconds to minutes
    3. C. Hours to days
    4. D. Minutes to an hour
    Show answer

    Answer: C. Hours to days

    Slow but most powerful.

64. In respiratory acidosis, the kidneys compensate by:

    1. A. Excreting extra sodium
    2. B. Retaining bicarbonate
    3. C. Excreting bicarbonate
    4. D. Retaining hydrogen ions
    Show answer

    Answer: B. Retaining bicarbonate

    They retain bicarbonate and excrete hydrogen ions. Chronic COPD patients show elevated bicarbonate.

65. In metabolic acidosis, the lungs compensate by:

    1. A. Reducing oxygen uptake
    2. B. Decreasing ventilation
    3. C. Increasing ventilation
    4. D. Retaining carbon dioxide
    Show answer

    Answer: C. Increasing ventilation

    Increased ventilation blows off carbon dioxide: Kussmaul respirations.

66. In metabolic alkalosis, the lungs compensate by:

    1. A. Increasing oxygen uptake
    2. B. Increasing ventilation
    3. C. Decreasing ventilation
    4. D. Blowing off carbon dioxide
    Show answer

    Answer: C. Decreasing ventilation

    Decreased ventilation retains carbon dioxide. Limited by hypoxia.

67. In respiratory alkalosis, the kidneys compensate by:

    1. A. Excreting potassium
    2. B. Excreting bicarbonate
    3. C. Retaining bicarbonate
    4. D. Retaining hydrogen
    Show answer

    Answer: B. Excreting bicarbonate

    Takes days.

68. Anion gap acidosis results from:

    1. A. Bicarbonate loss from severe diarrhea
    2. B. Renal tubular bicarbonate wasting
    3. C. Excess chloride from saline infusion
    4. D. Added acids such as lactate or ketones
    Show answer

    Answer: D. Added acids such as lactate or ketones

    Unmeasured acids such as lactate, ketones, or toxins widen the gap. MUDPILES mnemonic.

69. Non-anion gap acidosis results from:

    1. A. Methanol or ethylene glycol
    2. B. Bicarbonate loss, as in diarrhea
    3. C. Lactate buildup during shock
    4. D. Ketone buildup in diabetic crisis
    Show answer

    Answer: B. Bicarbonate loss, as in diarrhea

    Diarrhea and renal tubular acidosis are examples. Chloride rises to compensate.

70. Lactic acidosis occurs in:

    1. A. Shock, seizures, and severe exertion
    2. B. Hyperventilation with alkalosis
    3. C. Long-term loop diuretic therapy
    4. D. Prolonged vomiting of gastric acid
    Show answer

    Answer: A. Shock, seizures, and severe exertion

    Certain toxins also cause it. Anaerobic metabolism.

71. Ketoacidosis occurs in:

    1. A. Prolonged vomiting of stomach acid
    2. B. Diabetes, starvation, or alcoholism
    3. C. Overhydration with free water
    4. D. Renal failure without diabetes
    Show answer

    Answer: B. Diabetes, starvation, or alcoholism

    Uncontrolled diabetes, starvation, and alcohol excess cause it. Fat metabolism produces ketones.

72. Respiratory acidosis signs include:

    1. A. Tetany and carpopedal spasm
    2. B. Rapid, deep breathing and agitation
    3. C. Drowsiness, confusion, and headache
    4. D. Perioral tingling and lightheadedness
    Show answer

    Answer: C. Drowsiness, confusion, and headache

    These can progress to coma. Carbon dioxide narcosis.

73. Respiratory alkalosis signs include:

    1. A. Confusion progressing to coma
    2. B. Flushed skin and headache
    3. C. Tingling and carpopedal spasm
    4. D. Drowsiness and slow breathing
    Show answer

    Answer: C. Tingling and carpopedal spasm

    Lightheadedness is also common. Ionized calcium falls.

74. Metabolic alkalosis signs include:

    1. A. Rapid, deep Kussmaul breathing
    2. B. Twitching and slow breathing
    3. C. Tetany without any confusion
    4. D. Flushed skin and fruity breath
    Show answer

    Answer: B. Twitching and slow breathing

    Confusion, muscle twitching, and slow breathing occur. Often from vomiting or diuretics.

75. What is a mixed acid-base disorder?

    1. A. One primary disturbance with compensation
    2. B. Two or more primary disturbances at once
    3. C. One primary disturbance without compensation
    4. D. A disturbance that has been fully compensated
    Show answer

    Answer: B. Two or more primary disturbances at once

    A mixed disorder means two or more primary acid-base disturbances occur at the same time, as when cardiac arrest produces both respiratory and metabolic acidosis. A single disorder with expected compensation, an uncompensated single disorder, and a fully compensated single disorder each involve only one primary process; compensation is the body's response, not a second disorder.

76. Acidosis affects the heart by:

    1. A. Faster, more reliable conduction
    2. B. Better catecholamine response
    3. C. Stronger contractions and faster rate
    4. D. Weaker contraction and dysrhythmias
    Show answer

    Answer: D. Weaker contraction and dysrhythmias

    It reduces contractility and increases dysrhythmia risk. Catecholamines work poorly in acidosis.

77. Acidosis shifts the oxyhemoglobin curve:

    1. A. Left, holding oxygen tightly
    2. B. Right, easing oxygen release
    3. C. Right, holding oxygen tightly
    4. D. Upward, raising saturation
    Show answer

    Answer: B. Right, easing oxygen release

    A right shift releases oxygen more easily, a partial compensation.

78. Alkalosis shifts the oxyhemoglobin curve:

    1. A. Left, holding oxygen tightly
    2. B. Right, easing oxygen release
    3. C. Downward, lowering saturation
    4. D. Left, easing oxygen release
    Show answer

    Answer: A. Left, holding oxygen tightly

    A left shift holds oxygen more tightly. Tissue delivery falls.

79. Treating metabolic acidosis in shock focuses on:

    1. A. Diuretics to excrete acid
    2. B. Restoring tissue perfusion
    3. C. Routine sodium bicarbonate
    4. D. Hyperventilating the patient
    Show answer

    Answer: B. Restoring tissue perfusion

    Restoring perfusion lets aerobic metabolism resume. Fix the cause.

80. Bicarbonate administration can cause:

    1. A. Hypocapnia from less CO2 production
    2. B. Paradoxical intracellular acidosis
    3. C. Increased ionized calcium
    4. D. Hyperkalemia and low serum sodium
    Show answer

    Answer: B. Paradoxical intracellular acidosis

    It generates carbon dioxide, which enters cells and worsens intracellular acidosis; the sodium load can cause hypernatremia. The alkalosis it causes lowers ionized calcium rather than raising it.

81. Volume replacement in hypovolemia uses:

    1. A. Hypertonic saline for every patient
    2. B. Hypotonic fluids such as half saline
    3. C. Dextrose in water to restore volume
    4. D. Isotonic crystalloid or blood products
    Show answer

    Answer: D. Isotonic crystalloid or blood products

    Isotonic crystalloids are used initially, with blood products for hemorrhage. Blood replaces blood.

82. Over-resuscitation with crystalloid can cause:

    1. A. Coagulopathy, hypothermia, and edema
    2. B. Hypothermia only, without edema
    3. C. No harm if pressure normalizes
    4. D. Edema only, without clotting effects
    Show answer

    Answer: A. Coagulopathy, hypothermia, and edema

    Dilution causes coagulopathy. Permissive hypotension is used in some trauma.

83. Twelve hours after a major burn, a patient is hypotensive despite weight gain and massive edema. The best explanation is:

    1. A. Too much IV fluid has overloaded the vessels
    2. B. The burn has caused heart failure
    3. C. The kidneys are holding all the fluid in the blood
    4. D. Fluid has shifted into the tissues and left the circulation
    Show answer

    Answer: D. Fluid has shifted into the tissues and left the circulation

    Burns cause capillary leak, so plasma moves into the interstitium (third spacing). The patient gains weight and swells but has too little volume in the vessels. Overloaded vessels would cause hypertension and pulmonary edema. Heart failure and renal retention do not explain this pattern.

84. Fluid balance is regulated by:

    1. A. Hormones alone, without thirst
    2. B. Thirst, hormones, and the kidneys
    3. C. Thirst alone, without hormonal input
    4. D. The kidneys acting without hormones
    Show answer

    Answer: B. Thirst, hormones, and the kidneys

    Thirst, ADH, aldosterone, natriuretic peptides, and the kidneys are multiple overlapping systems.

85. Natriuretic peptides act to:

    1. A. Promote sodium and water excretion
    2. B. Constrict systemic arterioles
    3. C. Increase renal water reabsorption
    4. D. Promote sodium retention by kidneys
    Show answer

    Answer: A. Promote sodium and water excretion

    They are released by the atria and ventricles when the heart is stretched.

86. The thirst mechanism is triggered by:

    1. A. Rising osmolarity and low volume
    2. B. Low serum potassium levels
    3. C. Falling osmolarity and high volume
    4. D. High serum sodium, but not volume
    Show answer

    Answer: A. Rising osmolarity and low volume

    Hypothalamic osmoreceptors sense rising osmolarity; decreased volume also triggers thirst.

87. Older adults are prone to dehydration because:

    1. A. Their kidneys conserve water better
    2. B. They usually drink extra fluid daily
    3. C. They have more total body water
    4. D. Thirst and urine concentrating decline
    Show answer

    Answer: D. Thirst and urine concentrating decline

    Thirst sensation declines and renal concentrating ability falls. Add medications and mobility limits.

88. Burns cause fluid loss through:

    1. A. Bleeding from the burn wound
    2. B. Evaporation and capillary leak
    3. C. Increased sweating from intact skin
    4. D. Evaporation alone from wounds
    Show answer

    Answer: B. Evaporation and capillary leak

    Fluid evaporates from damaged skin and leaks from permeable capillaries. Massive volume requirements.

89. Diabetic ketoacidosis causes dehydration through:

    1. A. Osmotic diuresis plus vomiting
    2. B. Vomiting alone, without diuresis
    3. C. Severe watery diarrhea
    4. D. Profuse sweating from fever
    Show answer

    Answer: A. Osmotic diuresis plus vomiting

    Glucose causes osmotic diuresis. Patients may be liters down.

90. Rhabdomyolysis causes which electrolyte problem?

    1. A. Hypokalemia and hypercalcemia
    2. B. Hyponatremia and hypokalemia
    3. C. Hypernatremia and hypokalemia
    4. D. Hyperkalemia and hypocalcemia
    Show answer

    Answer: D. Hyperkalemia and hypocalcemia

    Released from damaged muscle.

91. Tumor lysis and crush injury share:

    1. A. Potassium loss causing hypokalemia
    2. B. Acid loss causing metabolic alkalosis
    3. C. Cell breakdown causing hyperkalemia
    4. D. Water loss causing hypernatremia
    Show answer

    Answer: C. Cell breakdown causing hyperkalemia

    Release of intracellular contents into the blood raises potassium.

92. Hyperventilation syndrome produces symptoms through:

    1. A. Hypoxia from rapid shallow breaths
    2. B. Metabolic acidosis from exertion
    3. C. Alkalosis lowering ionized calcium
    4. D. Hypercapnia from air trapping
    Show answer

    Answer: C. Alkalosis lowering ionized calcium

    Respiratory alkalosis lowers ionized calcium, causing tingling and carpopedal spasm.

93. Which patient is at highest risk of hypokalemia?

    1. A. Crush injury patient after extrication
    2. B. Patient in DKA before any treatment
    3. C. Dialysis patient who missed sessions
    4. D. Vomiting patient on loop diuretics
    Show answer

    Answer: D. Vomiting patient on loop diuretics

    Multiple losses.

94. Which patient is at highest risk of hyperkalemia?

    1. A. Dialysis patient who missed treatments
    2. B. Patient with respiratory alkalosis
    3. C. Patient with prolonged vomiting
    4. D. Patient taking a loop diuretic daily
    Show answer

    Answer: A. Dialysis patient who missed treatments

    Ask when they were last dialyzed.

95. Electrolyte disturbances most often present clinically as:

    1. A. Focal pain at a single site
    2. B. A characteristic skin rash
    3. C. Fever with a localized infection
    4. D. Weakness and dysrhythmias
    Show answer

    Answer: D. Weakness and dysrhythmias

    Altered mental status, weakness, and dysrhythmias are common. Nonspecific signs.