1. Lungs
Dr. Sama ul Haque

2. Objectives Define mediastinum.
Discuss the anatomical structure of lungs.
Enlist the relations of right and left lungs.
Give the blood and nerve supply of the lungs.

3. Mediastinum Definition:
A median septum or median partition between the two pleural cavities.

4. Boundaries of the Mediastinum
Superior boundary:
Superior thoracic aperture
Inferior boundary:
Diaphragm
Anterior boundary:
Sternum
Posterior boundary:
Bodies of vertebrae T1 to T12
Lateral boundaries:
Mediastinal parietal pleura
(left and right).

5. Gross Anatomy of the Lungs
Each lung has a conical shape, concave base rests upon the muscular diaphragm.
Its superior region is called Apex.
Toward the midline, the lungs are separated from each other by the Mediastinum.
The relatively broad, rounded surface in contact with the thoracic wall is called the Costal surface of the lung.

6. Lungs Left lung divided into 2 lobes by oblique fissure
smaller than the right lung.
cardiac notch accommodates the heart
Right Lung
divided into 3 lobes by oblique and horizontal fissure

7. Lungs and Pleura (Anterior view)

8. Lungs and Pleura
(Posterior view)

9. Lungs An apex A base 3 borders: Anterior Posterior Inferior
2 surfaces: Medial and costal.
Medial surface: Mediastinal & vertebral

10. Apex And Base of the lung
It extends up 1 inch above and behind the medial third of the clavicle.
Base:
It is concave in shape .
It is related to:
1- Diaphragmatic pleura.
2- Right copula of the diaphragm.
3- Liver (right lung) .
Liver, stomach (fundus), and spleen (left lung).

11. Borders of the lung
A. Anterior border It is a sharp border. The lower part of the anterior border of the left lung contains the cardiac notch (just below the cardiac notch there is a projection called the lingula). B. Posterior border It is a rounded border. C. Inferior border

12. Lobes &Fissures of the lungs
Right lung
Left lung
Three lobes:
Superior
Middle
Inferior
Fissures:
Oblique fissure
Transverse fissure
Two lobes
Superior
Inferior
Fissure:
Oblique fissure

13. Lobes and fissures of Lungs

14. Mediastinal Surface of the Right Lung
Cardiac impression (Right atrium).
Superior vena cava.
Inferior vena cava.
Right subclavian artery.
Right brachiocephalic vein
Azygos vein.
Esophagus.
Trachea.
Thymus

16. Mediastinal Surface of the Left Lung
Cardiac impression (Left ventricle).
Arch of Aorta.
Descending aorta.
Left subclavian artery.
Left brachiocephalic vein
Thoracic duct.
Esophagus.
Trachea.
Thymus

18. Hilum of the lungs
It gives passage to the structures forming the Root of the lung. 1. Bronchus 2. Pulmonary artery 3. Pulmonary veins 4. Hilar lymph nodes. 5. Bronchial vessels. 6. Pulmonary plexuses 7. Pulmonary ligament
Hilum of left lung
Hilum of right lung

19. Difference between the right and left lungs
Right Lung
Left Lung
Size and weight
Larger and heavier
Smaller and lighter
Length and breadth
Shorter and wider
Longer and narrower
Lobes
Fissures
Three
Two
Two lobes
One fissure
Anterior border
No cardiac notch
Cardiac notch and lingula.

20. Bronchial
Tree

21. Bronchopulmonary Segments

22. Bronchopulmonary Segments

23. Respiratory Bronchioles, Alveolar Ducts, and Alveoli
Lungs contain small sacs called alveoli.
They have a thin wall specialized to promote diffusion of gases between the alveolus and the blood in the pulmonary capillaries.

24. Respiratory Bronchioles, Alveolar Ducts, and Alveoli
Gas exchange can take place in the respiratory bronchioles and alveolar ducts as well as in the alveoli, each lung contains approximately 300 to 400 million alveoli.
The spongy nature of the lung is due to the packing of millions of alveoli together.

25. Respiratory Bronchioles
Alveolar Ducts
And
Alveoli

26. Blood supply of Lungs Pulmonary circulation: Bronchial circulation:
Bronchial arteries supply oxygenated blood to lungs, bronchial veins carry away deoxygenated blood from lung tissue.

27. Pulmonary Circulation

29. Nerve supply
Anterior and posterior pulmonary plexuses. a. Sympathetic component: (T2 to T5 sympathetic ganglia). b. Parasympathetic component (vagi)

31. Thank You