NURS 6501 ADVANCED PATHOPHYSIOLOGY WALDEN - WEEKS 1-6 MIDTERM –
EXAM-STYLE QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | PLUS RATIONALES | GUARANTEED PASS | 2026/27 LATEST UPDATE
| EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A 72-year-old male patient with a history of hypertension and heart failure
presents with worsening dyspnea, orthopnea, and peripheral edema. His
current medications include lisinopril and furosemide. An echocardiogram
reveals an ejection fraction of 35%. Which of the following pathophysiological
mechanisms is the primary driver of his fluid overload symptoms?
A. Decreased renal blood flow leading to activation of the renin-angiotensin-
aldosterone system
B. Increased systemic vascular resistance due to enhanced sympathetic nervous
system outflow
C. Reduced cardiac output resulting in decreased effective arterial blood volume
and subsequent sodium and water retention
D. Primary hepatic congestion leading to decreased albumin synthesis and
reduced plasma oncotic pressure
Correct Answer: C. Reduced cardiac output resulting in decreased effective
arterial blood volume and subsequent sodium and water retention
Rationale: The patient's presentation is consistent with heart failure with reduced
ejection fraction (HFrEF). The primary pathophysiological driver of fluid overload in
this context is the reduction in cardiac output. This decreases the effective arterial
blood volume, which is sensed by baroreceptors. This triggers a cascade of
,neurohormonal responses, including activation of the sympathetic nervous system
and the renin-angiotensin-aldosterone system (RAAS), leading to renal sodium and
water retention. This retention is a compensatory mechanism to increase preload
and maintain cardiac output, but it ultimately results in the clinical manifestations
of volume overload, such as dyspnea and edema. While options A and B are part of
this compensatory response, they are downstream effects of the initial decrease in
cardiac output. Option D is incorrect as it describes a consequence of right-sided
heart failure, not the primary driver of fluid overload in biventricular failure.
2. A 55-year-old male with a 40-pack-year smoking history and a recent
diagnosis of non-small cell lung cancer is being evaluated for a new onset of
syndrome of inappropriate antidiuretic hormone (SIADH). Which of the
following laboratory findings is most consistent with SIADH in this patient?
A. Serum osmolality 310 mOsm/kg, urine osmolality 100 mOsm/kg, serum
sodium 145 mEq/L
B. Serum osmolality 255 mOsm/kg, urine osmolality 600 mOsm/kg, serum sodium
125 mEq/L
C. Serum osmolality 290 mOsm/kg, urine osmolality 50 mOsm/kg, serum sodium
140 mEq/L
D. Serum osmolality 320 mOsm/kg, urine osmolality 800 mOsm/kg, serum
sodium 155 mEq/L
Correct Answer: B. Serum osmolality 255 mOsm/kg, urine osmolality 600
mOsm/kg, serum sodium 125 mEq/L
Rationale: SIADH is characterized by the inappropriate release of antidiuretic
hormone (ADH), leading to water retention. This results in a dilutional
,hyponatremia (serum sodium < 135 mEq/L) and a decreased serum osmolality (<
280 mOsm/kg). In response to the low serum osmolality, the kidneys should
normally excrete a dilute urine with a low osmolality. However, in SIADH, the urine
is inappropriately concentrated (urine osmolality > 100 mOsm/kg). This
combination of low serum sodium/hypoosmolality and inappropriately
concentrated urine is pathognomonic for SIADH. Option A shows hypernatremia
and hyperosmolality. Option C shows normal serum sodium and osmolality. Option
D shows hyperosmolality and hypernatremia, which is consistent with diabetes
insipidus.
3. A 68-year-old female with a history of osteoporosis and peptic ulcer disease
is prescribed celecoxib for osteoarthritis. She returns to the clinic one week
later with complaints of new-onset epigastric pain and dark, tarry stools. Which
of the following describes the primary pathophysiological mechanism causing
her new gastrointestinal symptoms?
A. Increased gastric acid secretion via direct stimulation of parietal cells
B. Inhibition of cyclooxygenase-1 (COX-1) leading to decreased prostaglandin
synthesis and reduced gastric mucosal protection
C. Over-the-counter use of a nonsteroidal anti-inflammatory drug (NSAID) and a
bisphosphonate causing synergistic mucosal damage
D. Direct cytotoxic effect of the drug on gastric epithelial cells leading to cellular
apoptosis
Correct Answer: B. Inhibition of cyclooxygenase-1 (COX-1) leading to decreased
prostaglandin synthesis and reduced gastric mucosal protection
, Rationale: Celecoxib is a COX-2 selective inhibitor; however, at higher doses or in
susceptible patients, it can still inhibit COX-1. COX-1 is constitutively expressed in
the gastric mucosa and is essential for the synthesis of prostaglandins. These
prostaglandins have protective functions, including inhibiting gastric acid secretion,
promoting mucus and bicarbonate secretion, and maintaining mucosal blood flow.
Inhibition of COX-1 leads to a reduction in these protective factors, making the
gastric mucosa vulnerable to injury from gastric acid and resulting in peptic ulcer
disease and gastrointestinal bleeding. The dark, tarry stools (melena) are indicative
of upper gastrointestinal bleeding. Option A is incorrect as NSAIDs do not stimulate
acid secretion. Option C is a scenario that could occur but does not describe the
primary mechanism. Option D is a less specific and not the primary mechanism for
NSAID-induced injury.
4. A 48-year-old male with a history of hypertension is started on
hydrochlorothiazide for blood pressure management. Two weeks later, he
presents to the emergency department with severe weakness, lethargy, and
muscle cramps. An EKG shows prominent U waves and ST-segment depression.
Which of the following electrolyte imbalances is most likely responsible for his
symptoms?
A. Hyperkalemia
B. Hypercalcemia
C. Hypokalemia
D. Hyponatremia
Correct Answer: C. Hypokalemia
EXAM-STYLE QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | PLUS RATIONALES | GUARANTEED PASS | 2026/27 LATEST UPDATE
| EXAM PREP | STUDY GUIDE | PRACTICE TEST
1. A 72-year-old male patient with a history of hypertension and heart failure
presents with worsening dyspnea, orthopnea, and peripheral edema. His
current medications include lisinopril and furosemide. An echocardiogram
reveals an ejection fraction of 35%. Which of the following pathophysiological
mechanisms is the primary driver of his fluid overload symptoms?
A. Decreased renal blood flow leading to activation of the renin-angiotensin-
aldosterone system
B. Increased systemic vascular resistance due to enhanced sympathetic nervous
system outflow
C. Reduced cardiac output resulting in decreased effective arterial blood volume
and subsequent sodium and water retention
D. Primary hepatic congestion leading to decreased albumin synthesis and
reduced plasma oncotic pressure
Correct Answer: C. Reduced cardiac output resulting in decreased effective
arterial blood volume and subsequent sodium and water retention
Rationale: The patient's presentation is consistent with heart failure with reduced
ejection fraction (HFrEF). The primary pathophysiological driver of fluid overload in
this context is the reduction in cardiac output. This decreases the effective arterial
blood volume, which is sensed by baroreceptors. This triggers a cascade of
,neurohormonal responses, including activation of the sympathetic nervous system
and the renin-angiotensin-aldosterone system (RAAS), leading to renal sodium and
water retention. This retention is a compensatory mechanism to increase preload
and maintain cardiac output, but it ultimately results in the clinical manifestations
of volume overload, such as dyspnea and edema. While options A and B are part of
this compensatory response, they are downstream effects of the initial decrease in
cardiac output. Option D is incorrect as it describes a consequence of right-sided
heart failure, not the primary driver of fluid overload in biventricular failure.
2. A 55-year-old male with a 40-pack-year smoking history and a recent
diagnosis of non-small cell lung cancer is being evaluated for a new onset of
syndrome of inappropriate antidiuretic hormone (SIADH). Which of the
following laboratory findings is most consistent with SIADH in this patient?
A. Serum osmolality 310 mOsm/kg, urine osmolality 100 mOsm/kg, serum
sodium 145 mEq/L
B. Serum osmolality 255 mOsm/kg, urine osmolality 600 mOsm/kg, serum sodium
125 mEq/L
C. Serum osmolality 290 mOsm/kg, urine osmolality 50 mOsm/kg, serum sodium
140 mEq/L
D. Serum osmolality 320 mOsm/kg, urine osmolality 800 mOsm/kg, serum
sodium 155 mEq/L
Correct Answer: B. Serum osmolality 255 mOsm/kg, urine osmolality 600
mOsm/kg, serum sodium 125 mEq/L
Rationale: SIADH is characterized by the inappropriate release of antidiuretic
hormone (ADH), leading to water retention. This results in a dilutional
,hyponatremia (serum sodium < 135 mEq/L) and a decreased serum osmolality (<
280 mOsm/kg). In response to the low serum osmolality, the kidneys should
normally excrete a dilute urine with a low osmolality. However, in SIADH, the urine
is inappropriately concentrated (urine osmolality > 100 mOsm/kg). This
combination of low serum sodium/hypoosmolality and inappropriately
concentrated urine is pathognomonic for SIADH. Option A shows hypernatremia
and hyperosmolality. Option C shows normal serum sodium and osmolality. Option
D shows hyperosmolality and hypernatremia, which is consistent with diabetes
insipidus.
3. A 68-year-old female with a history of osteoporosis and peptic ulcer disease
is prescribed celecoxib for osteoarthritis. She returns to the clinic one week
later with complaints of new-onset epigastric pain and dark, tarry stools. Which
of the following describes the primary pathophysiological mechanism causing
her new gastrointestinal symptoms?
A. Increased gastric acid secretion via direct stimulation of parietal cells
B. Inhibition of cyclooxygenase-1 (COX-1) leading to decreased prostaglandin
synthesis and reduced gastric mucosal protection
C. Over-the-counter use of a nonsteroidal anti-inflammatory drug (NSAID) and a
bisphosphonate causing synergistic mucosal damage
D. Direct cytotoxic effect of the drug on gastric epithelial cells leading to cellular
apoptosis
Correct Answer: B. Inhibition of cyclooxygenase-1 (COX-1) leading to decreased
prostaglandin synthesis and reduced gastric mucosal protection
, Rationale: Celecoxib is a COX-2 selective inhibitor; however, at higher doses or in
susceptible patients, it can still inhibit COX-1. COX-1 is constitutively expressed in
the gastric mucosa and is essential for the synthesis of prostaglandins. These
prostaglandins have protective functions, including inhibiting gastric acid secretion,
promoting mucus and bicarbonate secretion, and maintaining mucosal blood flow.
Inhibition of COX-1 leads to a reduction in these protective factors, making the
gastric mucosa vulnerable to injury from gastric acid and resulting in peptic ulcer
disease and gastrointestinal bleeding. The dark, tarry stools (melena) are indicative
of upper gastrointestinal bleeding. Option A is incorrect as NSAIDs do not stimulate
acid secretion. Option C is a scenario that could occur but does not describe the
primary mechanism. Option D is a less specific and not the primary mechanism for
NSAID-induced injury.
4. A 48-year-old male with a history of hypertension is started on
hydrochlorothiazide for blood pressure management. Two weeks later, he
presents to the emergency department with severe weakness, lethargy, and
muscle cramps. An EKG shows prominent U waves and ST-segment depression.
Which of the following electrolyte imbalances is most likely responsible for his
symptoms?
A. Hyperkalemia
B. Hypercalcemia
C. Hypokalemia
D. Hyponatremia
Correct Answer: C. Hypokalemia
