UExcel Pathophysiology 2 — Questions and Answers
Question 1: What is the pathophysiology of systemic inflammatory response syndrome (SIRS)?
- Localized immune response limited to one organ system
- Widespread, dysregulated inflammation affecting multiple organ systems following infection or injury (Correct answer)
- Autoimmune destruction of white blood cells
- Chronic low-grade inflammation limited to adipose tissue
Correct answer: Widespread, dysregulated inflammation affecting multiple organ systems following infection or injury
SIRS is a widespread inflammatory response to infection, trauma, or other insults that can progress to sepsis and multi-organ failure.
Question 2: Which mechanism best explains edema formation in inflammation?
- Decreased blood flow to the affected area
- Increased capillary permeability allows fluid and proteins to leak into interstitial spaces (Correct answer)
- Reduced lymphatic drainage only
- Decreased plasma protein production
Correct answer: Increased capillary permeability allows fluid and proteins to leak into interstitial spaces
Inflammatory mediators increase capillary permeability, causing protein-rich fluid to move from capillaries into interstitial tissue.
Question 3: What occurs during a myocardial infarction?
- The heart muscle hypertrophies due to increased workload
- Coronary artery occlusion causes ischemia and necrosis of myocardial tissue (Correct answer)
- Heart valves become calcified and stop functioning
- Pericardial fluid accumulates around the heart
Correct answer: Coronary artery occlusion causes ischemia and necrosis of myocardial tissue
A myocardial infarction occurs when a coronary artery is blocked (usually by plaque rupture and thrombosis), causing ischemic death of heart muscle.
Question 4: Chronic obstructive pulmonary disease (COPD) primarily causes:
- Decreased lung compliance and restrictive lung disease
- Airflow obstruction due to airway inflammation, mucus hypersecretion, and alveolar destruction (Correct answer)
- Pulmonary edema and fluid accumulation
- Increased diffusion capacity across the alveolar membrane
Correct answer: Airflow obstruction due to airway inflammation, mucus hypersecretion, and alveolar destruction
COPD, which includes chronic bronchitis and emphysema, causes obstructive airflow limitation and is strongly associated with cigarette smoking.
Question 5: What is the pathophysiological basis for hypertension-related end organ damage?
- Low blood pressure reduces perfusion to organs
- Chronically elevated pressure damages arterial walls and increases the workload on the heart and kidneys (Correct answer)
- Hypertension primarily affects only the lungs
- Elevated pressure reduces cardiac output and oxygen delivery
Correct answer: Chronically elevated pressure damages arterial walls and increases the workload on the heart and kidneys
Sustained high blood pressure damages blood vessel walls, leading to arteriosclerosis, cardiac hypertrophy, renal damage, and cerebrovascular disease.
Question 6: In shock, impaired tissue perfusion leads to cellular injury primarily through:
- Excess oxygen delivery to cells
- Hypoxia and anaerobic metabolism resulting in lactic acidosis and cell death (Correct answer)
- Decreased carbon dioxide levels in blood
- Bacterial toxin production only
Correct answer: Hypoxia and anaerobic metabolism resulting in lactic acidosis and cell death
When perfusion is inadequate, cells switch to anaerobic metabolism, producing lactic acid and eventually leading to cell dysfunction and death.
UExcel Pathophysiology 2
What is the pathophysiology of systemic inflammatory response syndrome (SIRS)?