Pulmonary

Question 1

Normal Lung

Answer 1

Airway Resistance: Low

Lung Compliance: Normal
🔑 Resistance is highest in medium-sized bronchi.

Question 2

Obstructive Lung Diseases

Answer 2

(Air can’t get out → ↑ resistance)

1. Chronic Obstructive Pulmonary Disease (COPD)
   Includes Emphysema & Chronic Bronchitis

Condition Airway Resistance Lung Compliance Tip

Emphysema ↑↑ ↑↑ Destruction of alveolar walls = floppy lungs

Chronic Bronchitis ↑↑ Normal/↓ Mucus and inflammation narrow airways

🔑 Both have ↓ FEV1/FVC ratio

COPD = “floppy balloons” → ↑ compliance, ↑ resistance

Question 3

Asthma

Answer 3

Airway Resistance: ↑↑ (reversible)

Lung Compliance: Normal
🔑 Bronchoconstriction + mucus plugging → reversible obstruction

Asthma = “tight pipes” → ↑↑ resistance, normal compliance

Question 4

Idiopathic Pulmonary Fibrosis (IPF

Answer 4

Airway Resistance: Normal or ↓

Lung Compliance: ↓↓↓
🔑 Stiff lungs = harder to expand, ↑ elastic recoil

Fibrosis = “tight balloons” → ↓ compliance, normal resistance

Question 5

ARDS (Acute Respiratory Distress Syndrome)

Answer 5

Airway Resistance: Normal

Lung Compliance: ↓↓
🔑 Inflammation + fluid in alveoli → “wet and stiff” lungs

ARDS = wet sponge → ↓ compliance, poor gas exchange

Question 6

Neonatal Respiratory Distress Syndrome (NRDS)

Answer 6

Airway Resistance: Normal

Lung Compliance: ↓↓↓
🔑 ↓ surfactant = ↑ surface tension = ↓ compliance