NSG 5140 Midterm Exam Review Adv
Pathophysiology Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. A patient with severe diarrhea develops metabolic acidosis. Which
compensatory response would the nurse expect?
A. Decreased respiratory rate
B. Increased bicarbonate retention by the kidneys
C. Increased respiratory rate and depth
D. Increased hydrogen ion secretion by the lungs
Answer: C. Increased respiratory rate and depth
Rationale: Metabolic acidosis causes a decrease in serum bicarbonate
and an increase in hydrogen ion concentration. The respiratory system
compensates rapidly through increased ventilation, which removes
carbon dioxide and helps raise blood pH. This response is commonly
referred to as respiratory compensation.
, 2. Which mechanism best explains why a patient with chronic
obstructive pulmonary disease may develop respiratory acidosis?
A. Excessive loss of bicarbonate through the kidneys
B. Inability to adequately eliminate carbon dioxide
C. Excessive production of lactic acid
D. Increased intestinal loss of hydrogen ions
Answer: B. Inability to adequately eliminate carbon dioxide
Rationale: Respiratory acidosis occurs when alveolar ventilation is
inadequate and carbon dioxide accumulates in the blood. Chronic CO₂
retention increases carbonic acid and hydrogen ion concentration. In
chronic respiratory acidosis, the kidneys partially compensate by
retaining bicarbonate and increasing hydrogen ion excretion.
3. A patient has a serum sodium concentration of 118 mEq/L. Which
cellular effect is most likely?
A. Water moves out of cells, causing cellular dehydration
B. Water moves into cells, causing cellular swelling
C. Sodium moves rapidly into cells
D. Potassium moves exclusively into the extracellular space
Answer: B. Water moves into cells, causing cellular swelling
,Rationale: Severe hyponatremia decreases extracellular osmolality.
Water therefore shifts from the extracellular compartment into cells
through osmosis. Brain cells are particularly vulnerable because cerebral
swelling can produce headache, confusion, seizures, and other
neurologic manifestations.
4. Which electrolyte abnormality is most strongly associated with
peaked T waves on an electrocardiogram?
A. Hypocalcemia
B. Hypernatremia
C. Hyperkalemia
D. Hypomagnesemia
Answer: C. Hyperkalemia
Rationale: Hyperkalemia alters cardiac membrane excitability and can
initially produce tall, peaked T waves. As potassium levels rise further,
conduction abnormalities, widening of the QRS complex, loss of P
waves, and potentially life-threatening dysrhythmias can occur.
5. Which finding is most characteristic of hypocalcemia?
, A. Shortened QT interval
B. Increased neuromuscular excitability
C. Decreased deep tendon reflexes
D. Flaccid paralysis as the primary manifestation
Answer: B. Increased neuromuscular excitability
Rationale: Calcium stabilizes neuronal and muscle membranes. Reduced
extracellular calcium increases neuromuscular excitability, potentially
producing paresthesias, muscle cramps, tetany, and positive Chvostek
or Trousseau signs. Hypocalcemia is also associated with QT
prolongation.
6. Which hormone primarily increases serum calcium concentration
by promoting bone resorption and increasing renal calcium
reabsorption?
A. Calcitonin
B. Parathyroid hormone
C. Insulin
D. Aldosterone
Answer: B. Parathyroid hormone
Pathophysiology Questions and Correct
Answers (Verified Answers) Plus Rationale
2027 Q&A| Instant Download Pdf
1. A patient with severe diarrhea develops metabolic acidosis. Which
compensatory response would the nurse expect?
A. Decreased respiratory rate
B. Increased bicarbonate retention by the kidneys
C. Increased respiratory rate and depth
D. Increased hydrogen ion secretion by the lungs
Answer: C. Increased respiratory rate and depth
Rationale: Metabolic acidosis causes a decrease in serum bicarbonate
and an increase in hydrogen ion concentration. The respiratory system
compensates rapidly through increased ventilation, which removes
carbon dioxide and helps raise blood pH. This response is commonly
referred to as respiratory compensation.
, 2. Which mechanism best explains why a patient with chronic
obstructive pulmonary disease may develop respiratory acidosis?
A. Excessive loss of bicarbonate through the kidneys
B. Inability to adequately eliminate carbon dioxide
C. Excessive production of lactic acid
D. Increased intestinal loss of hydrogen ions
Answer: B. Inability to adequately eliminate carbon dioxide
Rationale: Respiratory acidosis occurs when alveolar ventilation is
inadequate and carbon dioxide accumulates in the blood. Chronic CO₂
retention increases carbonic acid and hydrogen ion concentration. In
chronic respiratory acidosis, the kidneys partially compensate by
retaining bicarbonate and increasing hydrogen ion excretion.
3. A patient has a serum sodium concentration of 118 mEq/L. Which
cellular effect is most likely?
A. Water moves out of cells, causing cellular dehydration
B. Water moves into cells, causing cellular swelling
C. Sodium moves rapidly into cells
D. Potassium moves exclusively into the extracellular space
Answer: B. Water moves into cells, causing cellular swelling
,Rationale: Severe hyponatremia decreases extracellular osmolality.
Water therefore shifts from the extracellular compartment into cells
through osmosis. Brain cells are particularly vulnerable because cerebral
swelling can produce headache, confusion, seizures, and other
neurologic manifestations.
4. Which electrolyte abnormality is most strongly associated with
peaked T waves on an electrocardiogram?
A. Hypocalcemia
B. Hypernatremia
C. Hyperkalemia
D. Hypomagnesemia
Answer: C. Hyperkalemia
Rationale: Hyperkalemia alters cardiac membrane excitability and can
initially produce tall, peaked T waves. As potassium levels rise further,
conduction abnormalities, widening of the QRS complex, loss of P
waves, and potentially life-threatening dysrhythmias can occur.
5. Which finding is most characteristic of hypocalcemia?
, A. Shortened QT interval
B. Increased neuromuscular excitability
C. Decreased deep tendon reflexes
D. Flaccid paralysis as the primary manifestation
Answer: B. Increased neuromuscular excitability
Rationale: Calcium stabilizes neuronal and muscle membranes. Reduced
extracellular calcium increases neuromuscular excitability, potentially
producing paresthesias, muscle cramps, tetany, and positive Chvostek
or Trousseau signs. Hypocalcemia is also associated with QT
prolongation.
6. Which hormone primarily increases serum calcium concentration
by promoting bone resorption and increasing renal calcium
reabsorption?
A. Calcitonin
B. Parathyroid hormone
C. Insulin
D. Aldosterone
Answer: B. Parathyroid hormone
