This document discusses the differences between obstructive and restrictive lung diseases. Obstructive lung diseases involve obstruction in the airways from the trachea to the bronchioles, causing increased resistance to airflow. Restrictive lung diseases involve reduced expansion of the lung parenchyma and decreased total lung capacity. Pulmonary function tests can help distinguish the two, as obstructive diseases typically show decreased FEV1 and FVC with increased TLC, while restrictive diseases show decreased FEV1, FVC and TLC with a normal FEV1/FVC ratio. Common examples of each type of disease are also provided.

1. Obstructive vs Restrictive
Pulmonary Disease
Dr. Salman Ansari(MBBS)
Tutor, Dept. of Pathology
Kanachur Institute of Medical Sciences

2. ● Obstructive lung diseases
● Restrictive lung diseases
● Obstructive vs restrictive lung diseases

3. Obstructive lung diseases
Increase in resistance to airflow
Due to partial or complete obstruction at any level from the trachea to the
bronchioles
Examples of obstructive airway diseases:
- Emphysema
- Chronic Bronchitis
- Bronchial asthma
- Bronchiectasis

6. Restrictive pulmonary diseases
Reduced expansion of lung parenchyma and decreased total lung
capacity
X-ray shows ground-glass shadows

7. Types of restrictive lung disease
Restriction due to disorders of chest wall:
Diseases which restrict expansion of the chest wall due to problems
with chest wall/pleura/muscles
E.g: kyphoscoliosis
Poliomyelitis
Pleural diseases
Severe obesity
Interstitial and infiltrative diseases:
Diffuse involvement of parenchyma of the lung
E.g: Pneumoconiosis
Interstitial fibrosis

10. Spirometry: basic definitions
1. FVC
2. TLC
3. FEV1

11. FVC
● Forced Vital Capacity
● the amount of air that can be forcefully exhaled from your lungs
after breathing in as deeply as possible
● Normal: >80%
● But there is still some air left behind in the lungs - this is called
Residual Volume(RV)

12. TLC
● Total lung capacity
● volume of air in the lungs upon the maximum effort of
inspiration
● Normal: 6 liters
● TLC = FVC + RV

13. FEV1
forced expiratory volume in 1 second (FEV1)
the maximum amount of air that the subject can forcibly expel
during the first second following maximal inhalation
Normal: >80%

15. What happens in obstructive lung diseases?
To FEV1?
To FVC?
To TLC?

16. Obstructive
FEV1: ↓↓
Very low
FVC: ↓
low/almost normal
FEV1/FVC ratio: ↓↓
Very low
TLC: high

17. What happens in restrictive lung diseases?
To FEV1?
To FVC?
To TLC?

18. Restrictive
FEV1: ↓
low
FVC: ↓
low
FEV1/FVC ratio: normal(since both are low)
TLC: low

19. Obstructive Restrictive
FEV1 ↓ ↓ ↓
FVC ↓ /Normal ↓
FEV1/FVC ratio ↓ Normal
TLC ↑ ↓

20. Feature Obstructive pulmonary
disease
Restrictive pulmonary
disease
Nature of airway disease Obstruction at any level from
trachea to bronchiole
Reduced expansion of lung
parenchyma
Pulmonary function test TLC: ↑
FEV1/FVC: ↓
TLC: ↓
FEV1/FVC ratio: Normal
Chest X-ray Depends on cause B/l infiltrates showing ground
glass shadows
Examples - Chronic bronchitis
- Emphysema
- Bronchial asthma
- Bronchiectasis
- Chest wall disorders:
kyphoscoliosis,
poliomyelitis
- Interstitial lung diseases:
pneumoconioses

21. For notes,
scan:
References:
● Ramadas Nayak - Textbook of Pathology for Allied
Health Sciences
Questions:
salman.s.ansari92@gmail.com
For PPT, scan: