The document describes the anatomy of the pleura and lungs. The pleura is a serous membrane consisting of parietal and visceral layers that line the thoracic cavity and lungs. It forms a closed sac that contains a small amount of pleural fluid. The lungs are paired organs located in the thoracic cavity. Each lung is divided into lobes separated by fissures. The roots of the lungs contain structures like bronchi and blood vessels that connect the lungs to the mediastinum.

1. Pleura

2. Thoracic cavity
• Divided into
• A median partition
• Mediastinum
• Pleural sacs

3. Pleura
• Serous membrane
• Lining the chest cavity
• Consists of two layers

4. Pleura: Layers
• 1.Visceral
• 2.Parietal
• Cervical
• Costal
• Diaphragmatic
• Mediastinal
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5. Pleural cavity
• Space between
• Parietal andvisceral layers of pleura
• Closed sac
• Contains a small amount of pleural fluid
• Acts as a lubricant decreasing friction between the
pleurae

6. Visceral layer
• Otherwise - pulmonary pleura
• Covers - surface of lung
– Except hilum of lung
• Dips into fissures of lung
• Firmly adherent
• Inseparable from lungs
• Shares blood & nerve supply
with lung
• Develops from
splanchnopleuric mesoderm

7. Parietal pleura
• Thicker than visceral
• Lines
• Walls of thoracic cavity
• Diaphragm
• Mediastinum
• Subdivisions
– Costal pleura
– Diaphragmatic pleura
– Mediastinal pleura
– Cervical pleura

8. Cervical pleura
• Dome of the parietal pleura
• Extends into the root of neck
• 1inch above the medial end
of clavicle (2 inches above
the 1st costal cartilage)
– It is known as cupola
– Covers the apex of lung
– Not beyond the neck of 1st
rib

9. Cervical pleura - Relations
• Anteriorly
– Subclavian artery
– Scalenus anterior
• Posteriorly
– Neck of 1st rib
• Meidally
– Great vessels to H&N
• Laterally
– Scalenus medius

10. Supra pleural membrane
• Pleural diaphragm
• Cervical pleura + suprapleural membrane
• Musculo-fascial expansion
• Attaches
• Tip of transverse process of C7 vertebra
• Inner border of first rib
• Muscular part derived from
– Scalenus minimus muscle
• Fascial part derives from
– Endothoracic fascia
• Separates apex of lung & cervical pleura
– From structures of root of the neck

11. Costal pleura
• Lines the inner surface of
thoracic wall
• Ribs, costal cartilage
intercostal spaces and
posterior parts of thoracic
vertebrae
• Separated from thoracic
wall
• By a thin layer of loose
areolar tissue
(endothoracic fascia)

12. • Lines the mediastinal
surface
• Due to the hilum & the
structures
• Divided into
• 3 parts
• Above & below the hilum
• Continues
• From Costo mediastinal
line to costovertebral
line
Mediastinal pleura
• In the middle part
• Turns laterally
• Surrounds hilar structure and becomes visceral pleura
• Below hilum
• These layer collapsed and become pulmonary ligament

13. Pulmonary ligament
• Inferior to the lung root
• Similar to cuff of a jacket
• Functions
– Dead space
– Allows descent of the structures
in the root of the lung
– During inspiration

14. Diaphragmatic pleura
• Covers the superior surface of
diaphragm

15. Sites of parietal pleura
extends beyond thoracic cage
• 1. Above the medial third of clavicle
• 2. Beyond the right xiphicostal angle
• 3. Below costovertebral angle

16. Blood supply
• Arterial supply
– Visceral pleura
• Bronchial arteries
– Parietal pleura
• Intercostal, internal
thoracic &
musculophrenic arteries
• Venous drainage
– Visceral pleura
• Bronchial veins
– Parietal pleura
• Azygos & internal
thoracic

17. Nerve supply
• Parietal pleura
– Costal pleura
• Intercostal nerves
– Mediastinal pleura
• Phrenic nerve
– Diaphragmatic pleura
• Domes by the phrenic nerve
• Periphery by the lower six
intercostal nerves
• Pulmonary pleura
– Autonomic
• Sympathetic (2nd to 5th ganglia)
• Parasympathetic (Vagus)

18. • During inflammation of pleura
• If central and mediastinal part
• Root of neck & Shoulder
• Due to phrenic nerve (C3, 4 & 5)
• Which shares supra clavicular (C3 & 4)
• If lower costal & peripheral part
• Pain can be referred in anterior abdominal wall also
Referred pain

19. Surface marking
• Cervical pleura
– Sternoclavicular jt to junction of
middle & medial 3rd of clavicle
• Anterior margin / Sternal line /
costo mediastinal line
– Rt side:
• Sternoclavicular jt
• Mid point of sternal angle
• Midpoint xiphisternal jt
– Lt side:
• Same upto 4th costal cartilage
• Lt lat margin of sternum till 6th costal
cartilage

20. • Costo-diaphragmatic lines
• Where costal pleura continues with
diaphragmatic pleura
• Right side
• Xiphisternal joint
• 8th rib at midclavicular line
• 10th rib at mid axillary line
• Lateral to 12 thoracic spine
• Left side
• Starts from
• 6th costal cartilage

21. Costo vertebral line
• Where costal pleura continues with
mediastinal pleura posteriorly
• From
• 2 cm lateral to T1
• To
• 2cm lateral to T12

22. Pleural recesses
• Extended part of pleural cavity
beyond the lungs during normal
breathing
• Serve as reserve spaces of
pleural cavity
• Essential for expansion of lung
• Present on
• Anterior & inferior aspect
• They are
• Costomediastinal (anterior)
• Costodiaphragmatic (inferior)

23. • Located inferiorly
• Lies between costal &
diaphragmatic pleurae
• Dimensions
– 5 cm
– Lies opposite to 8th to 10th ribs along
midaxillary line
• Most dependent part
– Hence the fluid of pleural effusion first
collect here
– Related structures
– Right side
– Liver & kidney
– Left side
– Fundus of stomach, spleen & kidney
Costodiaphragmatic recess

24. Costomediastinal
recess
• Located anteriorly
• Lies between
– Costal & mediastinal
pleurae
– Between sternum &
costal cartilage
• Left costomediastinal
recess is large
– Due to cardiac notch
of left lung
– Wider at 4th to 6th
costal cartilages

25. Applied anatomy
• Pleura descends inferior to the costal
margin in three regions
• Right infrasternal angle
• Right and left costovertebral angles
• When making incisions through the
anterior abdominal wall
• Incision should not enter the pleural sac
since this results in pneumothorax

26. Pleurisy / pleuritis
• Inflammation of pleura
• Inflammed pleura becomes rough
• Friction between 2 layers
• Produce
• Sound
• Pain

27. Pneumothorax
• Air fills in the pleural cavity
• Leads to collapse of lungs
• Due to atomospheric air pressure
• Normally pleural cavity has
• - 4 - -5 cm of water (H2O) pressure
• Causes
• Penetrating thoracic wound
• Fractured rib
• Spontaneous rupture
• During stellate ganglion block
• By anaesthetist
• Exposure of kidney

28. Pleural effusion
• Presence of excess fluid in
the pleural cavity
• About 300 ml (normally 5-
10 ml)
• In Costodiaphragmatic
recess ,
• Causes
• Inflammation, TB,
malignancy, congestive heart
disease
• Dullness on percussion over
the effusion

29. Pleural tap
• Collection of pleural effusion
• Normally at
• 8th or 9th intercostal space
• In midaxillary line
• Needle should be inserted
• At lower part of intercostal space
• To avoid injury to intercostal nerve &
vessels

30. Lungs

31. Lungs
• A pair of respiratory organs
• Lies in thoracic cavity
• Right and left lung are separated
• By mediastinum

32. Lungs - Features
• Apex
• Base
• Borders
• Surfaces
• Costal Surface
• Medial Surface

33. Apex
• Lies above the level of anterior
end of 1st Rib
• Reaches 1-2 cm above medial
1/3rd of clavicle
• Coverings
• Cervical pleura
• Suprapleural membrane
• Grooved by
• Subclavian artery
• Subclavian vein

34. Base
• Semilunar and concave
• Rests on dome of Diaphragm
• Right sided dome is higher than left

35. Anterior border
• Corresponds to
• Anterior (Costomediastinal) line of
pleural reflection
• Deeply notched in the left lung
• Posterior to 5th costal cartilage
• Cardiac notch
• Lingula

36. Inferior border
• Thin and sharp
• Separates the base of lung from
the costal surface

37. Posterior border
• Thick and ill defined
• Fits into deep paravertebral gutter
• Extends from C7 to T10

38. Surfaces
• Costal surface
• In contact with costal pleura and
overlying thoracic wall
• Medial surface
• Posterior / Vertebral Part
• Anterior / Mediastinal Part

39. Relations of Posterior Part
• Vertebral Part
• Intervertebral Discs
• Posterior Intercostal Vessels
• Splanchic Nerves

40. Hilum
• A large depressed area
• Near the centre of the medial surface
• Various structures enter and leave
• Bronchi and pulmonary vessels

41. Root of the lung
• Hilar structures
• together contribute what is called the
root of the lung
• which connects the lung to the
mediastinum

42. Arrangement of structures in the root
• Before backwards
• Superior pulmonary vein
• Pulmonary artery
• Bronchus
• Above downwards
• Left side
• Pulmonary artery
• Bronchus
• Inferior pulmonary vein
Above downwards
Right Side
Eparterial Bronchus
Pulmonary Artery
Hyparterial Bronchus
Inferior Pulmonary
Vein

43. Fissures and lobes of lungs
• OBLIQUE FISSURE
• Begins posteriorly at the level of 5th
thoracic vertebra
• Passes antero-inferiorly in a spiral
course to meet the inferior margin close
to 6th costochondral junction
• HORIZONTAL FISSURE
• from anterior margin at the level of 4th
costal cartilage
• Runs horizontally backwards to meet
the oblique fissure in the mid-axillary
line