CP: Module 1.1: Chronic Pulmonary Pathophysiology - COPD Impairments and Limitations

Protects lungs from neutrophil enzymes.

What does Alpha-1 Antitrypsin (AAT) normally do?

Lung tissue breaks down faster, causing early emphysema.

What happens in AAT deficiency?

In the 30s, with average diagnosis by age 55.

When do symptoms of AAT deficiency usually start?

Shift from type I to type II fibers.

What muscle fiber change happens in COPD?

Work of breathing is increased.

Why do COPD patients have higher resting energy needs?

Only about 60%.

How much normal diaphragmatic strength do severe COPD patients have?

Myosin loss and chronic overuse shift fibers to endurance type.

Why is diaphragm strength reduced in COPD?

It shortens the diaphragm, putting it in a weaker position.

How does hyperinflation affect diaphragm function?

• Chronic Cough

• Sputum production

• Exertional dyspnea

• Barrel Chest

• Paradoxical Chest wall movements

• Decreased breath sounds

• Crackles (atelectasis)

• Early satiety and difficulty eating

• Balance and strength deficits

• Body weight changes*

• Cyanosis (severe cases)

What are common physical exam signs of COPD?

• Impaired FEV1/FVC Ratio (<.70)

• Reduced FEV1 (<80%)

• Air trapping (increased TLC)

• Reduced DLCO

• Flattened diaphragm

• Hypoxemia

• Hypercapnia

• Impaired ventilation

• Polycythemia

What are common diagnostic exam signs of COPD?

Low exercise capacity

Weakness

Poor balance

Slower gait

Dyspnea with minimal activity

What physical limitations are common in COPD?

The severity and airflow limitation based on FEV1 and other values.

What does pulmonary function testing help assess in COPD?

Airflow limitation and impaired gas exchange during activity.

What causes dyspnea with exertion in COPD?

Hyperinflated lungs,

flattened diaphragm,

and increased radiolucency.

What are common imaging findings in COPD?

In mild to moderate stages.

When does hypoxemia typically develop in COPD?

Both hypoxemia and hypercapnia can occur.

What happens when FEV1 drops below 1L or 50%?

It measures how well CO diffuses from alveoli to blood.

What is DLCO and what does it measure?

Alveolar and capillary membrane damage.

What lowers DLCO in COPD?

No — DLCO is usually normal in asthma.

Is DLCO reduced in asthma?

Severity of airflow limitation, exercise capacity, and oxygen levels.

What factors impact COPD prognosis?

Wheezing,

dyspnea,

chest tightness,

and dry cough.

What are common symptoms of asthma?

Reversible

Is asthma reversible or irreversible?

Exercise,

allergens,

smoke,

cold air,

infections.

What are triggers for asthma?

A severe asthma attack that can cause cyanosis and require emergency care.

What is status asthmaticus?