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,Advanced Pathophysiology: Exam 1 Practice Questions
Fluid and Electrolyte (28 Questions)
1. A 68-year-old female with a history of congestive heart failure is admitted with worsening
dyspnea and lower extremity edema. Which of the following Starling forces is most directly
responsible for the movement of fluid from the pulmonary capillaries into the interstitial
space, leading to pulmonary edema in this patient?
A. Decreased plasma oncotic pressure
B. Increased capillary hydrostatic pressure
C. Increased interstitial oncotic pressure
D. Decreased capillary hydrostatic pressure
2. A 72-year-old male with a history of cirrhosis and ascites is admitted with confusion. His
serum sodium is 118 mEq/L, and serum osmolality is 250 mOsm/kg. Which of the following
best describes the pathophysiologic mechanism of his hyponatremia?
A. Loss of sodium in excess of water from diuretic use
B. Impaired water excretion due to increased ADH from decreased effective circulating
volume
C. Primary polydipsia leading to water overload
D. Adrenal insufficiency causing mineralocorticoid deficiency
3. A 45-year-old male with a history of alcohol abuse is admitted with severe vomiting for
three days. His blood pressure is 90/60 mmHg, and heart rate is 115 bpm. Which of the
following intravenous fluids would be most appropriate for initial resuscitation of this
patient's intravascular volume deficit?
A. D5W (5% dextrose in water)
B. 0.45% normal saline (half-normal saline)
C. 0.9% normal saline
D. 3% normal saline
4. A 55-year-old female with chronic kidney disease presents with fatigue and muscle
weakness. Her serum potassium is 6.8 mEq/L, and ECG shows peaked T waves. Which of the
following is the primary mechanism by which hyperkalemia affects cardiac myocyte
depolarization?
A. Decreased potassium permeability during phase 3 repolarization
B. Resting membrane potential becomes less negative (closer to threshold)
C. Resting membrane potential becomes more negative (hyperpolarized)
D. Increased calcium influx through L-type calcium channels
, 5. A 62-year-old male with syndrome of inappropriate antidiuretic hormone (SIADH)
secondary to small cell lung cancer presents with confusion. His serum sodium is 122 mEq/L,
and serum osmolality is 250 mOsm/kg. Urine osmolality is 600 mOsm/kg. Which of the
following best explains the inappropriately concentrated urine in the setting of low serum
osmolality?
A. Aldosterone-mediated sodium retention
B. ADH-independent water reabsorption in the collecting duct
C. Persistent ADH activity despite low plasma osmolality
D. Increased glomerular filtration rate leading to water retention
6. A 34-year-old female with type 1 diabetes presents with polyuria and polydipsia. Her
serum glucose is 450 mg/dL, and serum sodium is 132 mEq/L. Which of the following best
explains the mechanism of her hyponatremia?
A. True sodium deficiency from osmotic diuresis
B. Pseudohyponatremia due to hyperlipidemia
C. Hyperglycemia-induced water shift from intracellular to extracellular space causing
dilutional hyponatremia
D. Increased ADH secretion due to hypovolemia
7. A 28-year-old male is brought to the emergency department after a motor vehicle accident
with significant blood loss. His blood pressure is 80/50 mmHg, and heart rate is 130 bpm.
Which of the following pressure changes is primarily responsible for the movement of
interstitial fluid into the intravascular space as an early compensatory mechanism?
A. Increased capillary hydrostatic pressure
B. Decreased capillary hydrostatic pressure
C. Increased plasma oncotic pressure
D. Decreased interstitial oncotic pressure
8. A 48-year-old female with a history of hypertension treated with hydrochlorothiazide
presents with fatigue and muscle cramps. Her serum potassium is 3.0 mEq/L, and serum
bicarbonate is 32 mEq/L. Which of the following is the most likely acid-base disturbance
accompanying her hypokalemia?
A. Respiratory acidosis
B. Metabolic acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
9. A 66-year-old male with congestive heart failure is admitted with acute pulmonary edema.
Which of the following Starling forces is the primary target of intravenous furosemide in
improving his symptoms?
,Advanced Pathophysiology: Exam 1 Practice Questions
Fluid and Electrolyte (28 Questions)
1. A 68-year-old female with a history of congestive heart failure is admitted with worsening
dyspnea and lower extremity edema. Which of the following Starling forces is most directly
responsible for the movement of fluid from the pulmonary capillaries into the interstitial
space, leading to pulmonary edema in this patient?
A. Decreased plasma oncotic pressure
B. Increased capillary hydrostatic pressure
C. Increased interstitial oncotic pressure
D. Decreased capillary hydrostatic pressure
2. A 72-year-old male with a history of cirrhosis and ascites is admitted with confusion. His
serum sodium is 118 mEq/L, and serum osmolality is 250 mOsm/kg. Which of the following
best describes the pathophysiologic mechanism of his hyponatremia?
A. Loss of sodium in excess of water from diuretic use
B. Impaired water excretion due to increased ADH from decreased effective circulating
volume
C. Primary polydipsia leading to water overload
D. Adrenal insufficiency causing mineralocorticoid deficiency
3. A 45-year-old male with a history of alcohol abuse is admitted with severe vomiting for
three days. His blood pressure is 90/60 mmHg, and heart rate is 115 bpm. Which of the
following intravenous fluids would be most appropriate for initial resuscitation of this
patient's intravascular volume deficit?
A. D5W (5% dextrose in water)
B. 0.45% normal saline (half-normal saline)
C. 0.9% normal saline
D. 3% normal saline
4. A 55-year-old female with chronic kidney disease presents with fatigue and muscle
weakness. Her serum potassium is 6.8 mEq/L, and ECG shows peaked T waves. Which of the
following is the primary mechanism by which hyperkalemia affects cardiac myocyte
depolarization?
A. Decreased potassium permeability during phase 3 repolarization
B. Resting membrane potential becomes less negative (closer to threshold)
C. Resting membrane potential becomes more negative (hyperpolarized)
D. Increased calcium influx through L-type calcium channels
, 5. A 62-year-old male with syndrome of inappropriate antidiuretic hormone (SIADH)
secondary to small cell lung cancer presents with confusion. His serum sodium is 122 mEq/L,
and serum osmolality is 250 mOsm/kg. Urine osmolality is 600 mOsm/kg. Which of the
following best explains the inappropriately concentrated urine in the setting of low serum
osmolality?
A. Aldosterone-mediated sodium retention
B. ADH-independent water reabsorption in the collecting duct
C. Persistent ADH activity despite low plasma osmolality
D. Increased glomerular filtration rate leading to water retention
6. A 34-year-old female with type 1 diabetes presents with polyuria and polydipsia. Her
serum glucose is 450 mg/dL, and serum sodium is 132 mEq/L. Which of the following best
explains the mechanism of her hyponatremia?
A. True sodium deficiency from osmotic diuresis
B. Pseudohyponatremia due to hyperlipidemia
C. Hyperglycemia-induced water shift from intracellular to extracellular space causing
dilutional hyponatremia
D. Increased ADH secretion due to hypovolemia
7. A 28-year-old male is brought to the emergency department after a motor vehicle accident
with significant blood loss. His blood pressure is 80/50 mmHg, and heart rate is 130 bpm.
Which of the following pressure changes is primarily responsible for the movement of
interstitial fluid into the intravascular space as an early compensatory mechanism?
A. Increased capillary hydrostatic pressure
B. Decreased capillary hydrostatic pressure
C. Increased plasma oncotic pressure
D. Decreased interstitial oncotic pressure
8. A 48-year-old female with a history of hypertension treated with hydrochlorothiazide
presents with fatigue and muscle cramps. Her serum potassium is 3.0 mEq/L, and serum
bicarbonate is 32 mEq/L. Which of the following is the most likely acid-base disturbance
accompanying her hypokalemia?
A. Respiratory acidosis
B. Metabolic acidosis
C. Respiratory alkalosis
D. Metabolic alkalosis
9. A 66-year-old male with congestive heart failure is admitted with acute pulmonary edema.
Which of the following Starling forces is the primary target of intravenous furosemide in
improving his symptoms?
