,NURS 251 Portage Pathophysiology &
Pharmacology Study Guide – Endocrine,
Diabetes, and Medication Review 2026
Question 1:
A patient with type 1 diabetes mellitus is admitted with diabetic ketoacidosis (DKA).
Which pathophysiological mechanism is the primary cause of the metabolic acidosis
seen in this condition?
A) Increased renal excretion of bicarbonate
B) Excessive breakdown of dietary proteins into amino acids
C) Unchecked lipolysis leading to excess ketone body production
D) Respiratory depression causing CO₂ retention
Rationale: The correct answer is C. In type 1 diabetes, absolute insulin deficiency prevents
glucose from entering cells. The body shifts to fat metabolism (lipolysis), which produces
excessive ketone bodies (acetoacetic acid, beta-hydroxybutyric acid). These acids
overwhelm the buffer systems, causing metabolic acidosis. Option A is incorrect because
renal bicarbonate loss is not the primary driver in DKA. Option B is incorrect because
protein breakdown contributes to gluconeogenesis but not directly to acidosis. Option D
describes respiratory acidosis, not the metabolic acidosis seen in DKA.
Question 2:
A patient is diagnosed with essential hypertension. Which pathophysiological
mechanism is most commonly associated with the development of this condition?
,A) Renal artery stenosis
B) Pheochromocytoma
C) Increased systemic vascular resistance (SVR) due to arteriolar vasoconstriction
D) Coarctation of the aorta
Rationale: The correct answer is C. Essential (primary) hypertension accounts for 90–95%
of cases and is characterized by increased SVR due to chronic arteriolar vasoconstriction.
This is driven by overactivity of the sympathetic nervous system and the renin-
angiotensin-aldosterone system (RAAS). Option A describes secondary hypertension from
renal artery stenosis. Option B describes a tumor that secretes catecholamines, also a
secondary cause. Option D is a congenital vascular anomaly causing secondary
hypertension.
Question 3:
A patient with chronic obstructive pulmonary disease (COPD) has a PaCO₂ of 55 mmHg
and a pH of 7.30. Which pathophysiological change is most likely responsible for this
arterial blood gas result?
A) Increased alveolar ventilation
B) Diffusion impairment across the alveolar-capillary membrane
C) Airway obstruction leading to hypoventilation and CO₂ retention
D) Right-to-left cardiac shunt
Rationale: The correct answer is C. COPD causes airway obstruction (from chronic
bronchitis and emphysema), which leads to hypoventilation. This results in decreased CO₂
elimination, causing hypercapnia (elevated PaCO₂) and respiratory acidosis (low pH).
Option A is incorrect because alveolar ventilation is decreased, not increased. Option B is
incorrect because diffusion impairment primarily affects O₂ exchange, not CO₂ retention.
Option D is incorrect because shunting is not the primary mechanism in COPD.
, Question 4:
A patient with liver cirrhosis develops ascites. Which pathophysiological mechanism is
the primary contributor to this complication?
A) Increased cardiac output
B) Decreased antidiuretic hormone (ADH) secretion
C) Portal hypertension and decreased plasma oncotic pressure from
hypoalbuminemia
D) Increased glomerular filtration rate (GFR)
Rationale: The correct answer is C. In cirrhosis, scar tissue obstructs blood flow through the
liver, causing portal hypertension. Additionally, the damaged liver cannot produce
adequate albumin, leading to decreased plasma oncotic pressure. Both mechanisms drive
fluid into the peritoneal cavity, causing ascites. Option A is incorrect because cardiac
output is often increased in cirrhosis but does not directly cause ascites. Option B is
incorrect because ADH is typically elevated, not decreased. Option D is incorrect because
GFR often decreases in advanced liver disease.
Question 5:
A patient with rheumatoid arthritis has joint swelling, pain, and morning stiffness. Which
pathophysiological process is responsible for these manifestations?
A) Degeneration of articular cartilage due to mechanical wear and tear
B) Chronic autoimmune inflammation of the synovial membrane with pannus
formation
C) Deposition of uric acid crystals in the synovial fluid
D) Infection of the joint space by bacterial pathogens
Pharmacology Study Guide – Endocrine,
Diabetes, and Medication Review 2026
Question 1:
A patient with type 1 diabetes mellitus is admitted with diabetic ketoacidosis (DKA).
Which pathophysiological mechanism is the primary cause of the metabolic acidosis
seen in this condition?
A) Increased renal excretion of bicarbonate
B) Excessive breakdown of dietary proteins into amino acids
C) Unchecked lipolysis leading to excess ketone body production
D) Respiratory depression causing CO₂ retention
Rationale: The correct answer is C. In type 1 diabetes, absolute insulin deficiency prevents
glucose from entering cells. The body shifts to fat metabolism (lipolysis), which produces
excessive ketone bodies (acetoacetic acid, beta-hydroxybutyric acid). These acids
overwhelm the buffer systems, causing metabolic acidosis. Option A is incorrect because
renal bicarbonate loss is not the primary driver in DKA. Option B is incorrect because
protein breakdown contributes to gluconeogenesis but not directly to acidosis. Option D
describes respiratory acidosis, not the metabolic acidosis seen in DKA.
Question 2:
A patient is diagnosed with essential hypertension. Which pathophysiological
mechanism is most commonly associated with the development of this condition?
,A) Renal artery stenosis
B) Pheochromocytoma
C) Increased systemic vascular resistance (SVR) due to arteriolar vasoconstriction
D) Coarctation of the aorta
Rationale: The correct answer is C. Essential (primary) hypertension accounts for 90–95%
of cases and is characterized by increased SVR due to chronic arteriolar vasoconstriction.
This is driven by overactivity of the sympathetic nervous system and the renin-
angiotensin-aldosterone system (RAAS). Option A describes secondary hypertension from
renal artery stenosis. Option B describes a tumor that secretes catecholamines, also a
secondary cause. Option D is a congenital vascular anomaly causing secondary
hypertension.
Question 3:
A patient with chronic obstructive pulmonary disease (COPD) has a PaCO₂ of 55 mmHg
and a pH of 7.30. Which pathophysiological change is most likely responsible for this
arterial blood gas result?
A) Increased alveolar ventilation
B) Diffusion impairment across the alveolar-capillary membrane
C) Airway obstruction leading to hypoventilation and CO₂ retention
D) Right-to-left cardiac shunt
Rationale: The correct answer is C. COPD causes airway obstruction (from chronic
bronchitis and emphysema), which leads to hypoventilation. This results in decreased CO₂
elimination, causing hypercapnia (elevated PaCO₂) and respiratory acidosis (low pH).
Option A is incorrect because alveolar ventilation is decreased, not increased. Option B is
incorrect because diffusion impairment primarily affects O₂ exchange, not CO₂ retention.
Option D is incorrect because shunting is not the primary mechanism in COPD.
, Question 4:
A patient with liver cirrhosis develops ascites. Which pathophysiological mechanism is
the primary contributor to this complication?
A) Increased cardiac output
B) Decreased antidiuretic hormone (ADH) secretion
C) Portal hypertension and decreased plasma oncotic pressure from
hypoalbuminemia
D) Increased glomerular filtration rate (GFR)
Rationale: The correct answer is C. In cirrhosis, scar tissue obstructs blood flow through the
liver, causing portal hypertension. Additionally, the damaged liver cannot produce
adequate albumin, leading to decreased plasma oncotic pressure. Both mechanisms drive
fluid into the peritoneal cavity, causing ascites. Option A is incorrect because cardiac
output is often increased in cirrhosis but does not directly cause ascites. Option B is
incorrect because ADH is typically elevated, not decreased. Option D is incorrect because
GFR often decreases in advanced liver disease.
Question 5:
A patient with rheumatoid arthritis has joint swelling, pain, and morning stiffness. Which
pathophysiological process is responsible for these manifestations?
A) Degeneration of articular cartilage due to mechanical wear and tear
B) Chronic autoimmune inflammation of the synovial membrane with pannus
formation
C) Deposition of uric acid crystals in the synovial fluid
D) Infection of the joint space by bacterial pathogens
