NUR 546/NUR546 Exam 3 V2 | Advanced
Pathophysiology Q&A with Rationale |
William Paterson University
1. Which mechanism is primarily responsible for the development of pulmonary edema in a
patient with left-sided heart failure?
A. Increased pulmonary capillary oncotic pressure
B. Increased pulmonary capillary hydrostatic pressure
C. Decreased capillary permeability
D. Obstruction of the lymphatic system
Correct Answer: B
Expert Explanation: In left-sided heart failure, the left ventricle cannot pump blood
efficiently, leading to a backup of blood into the pulmonary circulation. This backup
increases the hydrostatic pressure within the pulmonary capillaries, forcing fluid into the
interstitial spaces and alveoli. This process is the hallmark of cardiogenic pulmonary
edema, causing symptoms like dyspnea and crackles.
2. A patient is diagnosed with Chronic Obstructive Pulmonary Disease (COPD) characterized
by permanent enlargement of the gas-exchange airways. Which condition does this describe?
A. Chronic bronchitis
B. Asthma
,C. Emphysema
D. Bronchiectasis
Correct Answer: C
Expert Explanation: Emphysema is defined by the permanent destruction and
enlargement of the air spaces distal to the terminal bronchioles. This occurs due to the
breakdown of elastin in the alveolar walls by proteases like elastase. Unlike chronic
bronchitis, which focuses on mucus production, emphysema focuses on the loss of elastic
recoil and surface area for gas exchange.
3. Which lab value is the most sensitive indicator for declining renal function in a patient with
Chronic Kidney Disease (CKD)?
A. Glomerular Filtration Rate (GFR)
B. Serum Creatinine
C. Blood Urea Nitrogen (BUN)
D. Urine Specific Gravity
Correct Answer: A
Expert Explanation: The Glomerular Filtration Rate (GFR) is considered the best overall
index of kidney function because it measures how much blood passes through the
glomeruli each minute. While serum creatinine is often used, it can be influenced by muscle
mass and diet, making GFR a more precise measurement for staging CKD. A decline in GFR
indicates a reduction in the number of functioning nephrons.
, 4. What is the primary pathophysiology behind the development of type I hypersensitivity in
extrinsic asthma?
A. IgG-mediated destruction of alveolar cells
B. Immune complex deposition in the bronchioles
C. T-cell mediated delayed hypersensitivity
D. IgE-mediated mast cell degranulation
Correct Answer: D
Expert Explanation: Extrinsic asthma involves an allergen-induced IgE response where
IgE antibodies bind to mast cells in the airway mucosa. Upon re-exposure, the allergen
cross-links the IgE, causing mast cell degranulation and the release of inflammatory
mediators like histamine and leukotrienes. These mediators lead to bronchoconstriction,
increased mucus production, and airway edema.
5. Why do patients with chronic renal failure often develop anemia?
A. Inadequate production of erythropoietin by the kidneys
B. Chronic blood loss during dialysis
C. Increased destruction of red blood cells in the spleen
D. Iron deficiency due to dietary restrictions
Correct Answer: A
Pathophysiology Q&A with Rationale |
William Paterson University
1. Which mechanism is primarily responsible for the development of pulmonary edema in a
patient with left-sided heart failure?
A. Increased pulmonary capillary oncotic pressure
B. Increased pulmonary capillary hydrostatic pressure
C. Decreased capillary permeability
D. Obstruction of the lymphatic system
Correct Answer: B
Expert Explanation: In left-sided heart failure, the left ventricle cannot pump blood
efficiently, leading to a backup of blood into the pulmonary circulation. This backup
increases the hydrostatic pressure within the pulmonary capillaries, forcing fluid into the
interstitial spaces and alveoli. This process is the hallmark of cardiogenic pulmonary
edema, causing symptoms like dyspnea and crackles.
2. A patient is diagnosed with Chronic Obstructive Pulmonary Disease (COPD) characterized
by permanent enlargement of the gas-exchange airways. Which condition does this describe?
A. Chronic bronchitis
B. Asthma
,C. Emphysema
D. Bronchiectasis
Correct Answer: C
Expert Explanation: Emphysema is defined by the permanent destruction and
enlargement of the air spaces distal to the terminal bronchioles. This occurs due to the
breakdown of elastin in the alveolar walls by proteases like elastase. Unlike chronic
bronchitis, which focuses on mucus production, emphysema focuses on the loss of elastic
recoil and surface area for gas exchange.
3. Which lab value is the most sensitive indicator for declining renal function in a patient with
Chronic Kidney Disease (CKD)?
A. Glomerular Filtration Rate (GFR)
B. Serum Creatinine
C. Blood Urea Nitrogen (BUN)
D. Urine Specific Gravity
Correct Answer: A
Expert Explanation: The Glomerular Filtration Rate (GFR) is considered the best overall
index of kidney function because it measures how much blood passes through the
glomeruli each minute. While serum creatinine is often used, it can be influenced by muscle
mass and diet, making GFR a more precise measurement for staging CKD. A decline in GFR
indicates a reduction in the number of functioning nephrons.
, 4. What is the primary pathophysiology behind the development of type I hypersensitivity in
extrinsic asthma?
A. IgG-mediated destruction of alveolar cells
B. Immune complex deposition in the bronchioles
C. T-cell mediated delayed hypersensitivity
D. IgE-mediated mast cell degranulation
Correct Answer: D
Expert Explanation: Extrinsic asthma involves an allergen-induced IgE response where
IgE antibodies bind to mast cells in the airway mucosa. Upon re-exposure, the allergen
cross-links the IgE, causing mast cell degranulation and the release of inflammatory
mediators like histamine and leukotrienes. These mediators lead to bronchoconstriction,
increased mucus production, and airway edema.
5. Why do patients with chronic renal failure often develop anemia?
A. Inadequate production of erythropoietin by the kidneys
B. Chronic blood loss during dialysis
C. Increased destruction of red blood cells in the spleen
D. Iron deficiency due to dietary restrictions
Correct Answer: A
