Bronchi, Lungs, Pleura

Question 1

How do the left and right lobes divide?

Answer 1

The left bronchus divides into lobar bronchi within the lung. The right bronchus may divide into lobar bronchi in the hilum (before entering the lung).

Question 2

What is the lung pleura?

Answer 2

thin layer of flattened cells supported by connective tissue lining each pleural cavity and covering exterior of lungs

• Visceral Pleura - covers surface lungs and lines fissures between the lobes
• Parietal Pleura - lines inner surface of chest walls

Question 3

What is the pleural cavity?

Answer 3

usually collapsed, and moist surfaces allow lungs to glide as expand and collapse

Question 4

What is the Pleural origin:

Answer 4

pleural cavities inside chest wall lined by parietal pleura as lung buds and grows into them

Question 5

Structures passing through lung:

Answer 5

IVC at T8 (and right phrenic nerve), Oesophagus at T10 (and CNX) and Aorta at T12 (and thoracic duct/azygous vein)

Question 6

What is the innervation of the lung?

Answer 6

• Anterior and posterior pulmonary plexus
• Lie anterior and posterior to tracheal bifurcation and main bronchi
• Branches of plexuses originate from sympathetic trunk (dilate) and vagus (constrict)

Question 7

What is the lymphatic drainage of the lung?

Answer 7

Trachebronchial nodes around roots of lobar and main bronchi

Extend from within lung, through hilum at root and into posterior mediastinum

Question 8

Where do phrenic nerves arise?

Answer 8

Anterior rami of C3,4,5

Question 9

What are the surface landmarks for the lung fissures?

Answer 9

Oblique fissure:
Begins posteriorly at T4–>passes inferiorly crossing R4–>ICS4–>R5 at MAL–>continues anteriorly along R4

Horizontal fissure:
Crosses R5 in MAL–>continues anteriorly–>cross ICS4–>follow R4 to sternum

Question 10

What are the surface landmarks of right parietal pleura?

Answer 10

• Apex of lung 2cm superior to medial third of clavicle
• Over sternoclavicular joint
• Right of sternal angle
• Right of 4th costal cartilage
• Right of xiphoid (taken as 6th costal cartilage)
• Mid clavicular line R8 (above costal margin)
• MAL R10 rib costal margin
• Posterior lower border is scapular line crossing R12

Question 11

What are the surface landmarks of left parietal pleura?

Answer 11

• Similair to left BUT
• CC4 and Xiphoid point deflect to left because cardiac notch (4-5cm)
• deflects the anterior margin of left pleura lateral to sternum between 4-7th costal cartilage

Question 12

What are the surface landmarks of the right lung?

Answer 12

• Follows pleural border until 6CC
• Lower border:
  ○ MCL at R6 anteriorly
  ○ MAL at R8 laterally
  ○ Scapular line at R10 posterioly

Question 13

What are the surface landmarks for the left lung?

Answer 13

• Same as right BUT
• Mediastinal relfection below CC4
• Below CC4 cardiac noth deviates by 2-3cm lateral at 5CC
• Lower border same as right

Question 14

What happens to the costodiaphragmatic recess during expriration?

Answer 14

During expiration contains no lung because margin of diaphragm pressed closely against lower part of rib cage