Thorax, Tracheobronchial Tree & Lungs

Question 1

What vertebral levels are the following found at?
Suprasternal (jugular) notch
Sternal angle
Xiphoid process

Answer 1

Suprasternal (jugular) notch - T2
Sternal angle - T4/5
Xiphoid process - T9/10

Question 2

Which vertebrae would articulate with rib 5?

Answer 2

T4 AND T5

Most ribs articulate with their own vertebrae and the one ABOVE

Question 3

How can the ribs be classified?

Answer 3

Vertebrosternal - Ribs 1-7
Vertebrocostal - Ribs 8-10
Floating - Ribs 11 and 12

Question 4

Within which intercostal muscles does the main neurovascular bundle run?

Answer 4

Between the internal and innermost intercostal mucle layers

Question 5

What are the external and internal intercostal muscles involved in?

Answer 5

External - inspiration

Internal - expiration

Question 6

Should chest drains be inserted in the superior or inferior part of intercostal spaces?

Answer 6

Inferior - avoid main neurovascular bundle

Question 7

What is the revised triangle of safety? What is it used for?

Answer 7

Thoracostomy (chest drain)

4th intercostal space between midaxillary line and ant axillary fold

Question 8

Which is the nerve supply of the intercostal space and the surrounding tissue? (both motor and sensory)

Answer 8

Ventral rami of spinal nerves

Dermatomal arrangement - e.g. shingles can be to a dermatome

Question 9

What can lead to Horner’s syndrome?

Answer 9

Pancoast tumour - apical lung tumour

Question 10

What do anterior and posterior instercostal arteries arise from? What happens to both of them?

Answer 10

Ant - arise from internal thoracic and musculophrenic a
Post - arise from descending aorta
Form an anatomoses

Question 11

What is the drainage system of the thoracic wall?

Answer 11

UNPAIRED (Azygous) system
R.side - azygous v -> SVC
L.side - accessory azygous or hemiazygous v -> cross midline -> SVC

Question 12

Where does the thoracic duct drain to?

Answer 12

Left subclavian vein

Question 13

What nerve innervates the diaphragm?

Answer 13

Phrenic nerve = C3,4,5 - motor and sensory
+ sensory on periphery - intercostal nerves
Gallbladder inflammation - shoulder pain

Question 14

At what vertebral levels do structures pierce the diaphragm?

Answer 14

IVC - T8
Oesophagus - T11-T12
Aorta - T12

Question 15

What congenital diaphragmatic defects can occur?

Answer 15

Posterolaterally - Bochdalek

Retrosternally - Morgagni

Question 16

Where does the respiratory system develop from?

Answer 16

Outgrowth of the gut tube - resp diverticulum (4 wks)

Lung/bronchial buds -> splanchno-pleuric Mesoderm

Question 17

Embryologically, how does the oesophagus separate from the trachea?

Answer 17

Tracheo-oesophageal septum

Question 18

How many bronchial buds are there on the right and left side?

Answer 18

R = 3 
L = 2

Question 19

Why might a premature baby have very little chance of survival before 26 weeks?

Answer 19

Respiratory epithelia begins developing at 26 weeks

Question 20

When do all major lung parts develop?

Answer 20

16 weeks

Full lung maturation = 7-10 yrs

Question 21

What fissures and lobes do the right and left lungs have?

Answer 21

R = 3 lobes/ oblique and horizontal fissure
L = 2 lobes/ oblique fissure

Question 22

Where does the phrenic nerve and vagus nerve pass in relation to the lung?

Answer 22

Phrenic = Anterior to hilum
Vagus = posterior to hilum

Question 23

Where do recurrent laryngeal nerves branch from and how do they enter the thorax?

Answer 23

Vagus nerve
R. RLN recurs at right lung apex under right subclavian artery
L. RLN recurs at lung hilum/aortic arch

Question 24

So what might happen in a patient with an aortic arch aneurysm?

Answer 24

Hemiparalysis of vocal cords - L. RLN -> hoarse voice

Question 25

What is the pleural cavity?

Answer 25

Space between visceral and parietal pleura - surface tension holds them close together

Question 26

What is pleural catch?

Answer 26

Slouching - push visceral and parietal pleura together, and fluid out.
Stop slouching - fluid returns - parietal pleura is somatically innervated - feel a stabbing pain

Question 27

What is haemothorax?

Answer 27

Air in pleural cavity

Question 28

What is effusion?

Answer 28

Fluid leaking out of lung into pleural cavity

Question 29

What is tension pneumothorax?

Answer 29

Air entering pleural cavity but not leaving - constant overfilling leads to:
Mediastinal shift
Tracheal deviation
Diaphragmatic depression
Unilateral hyperinflation
Increased intercostal space size
Hyper-resonant

Question 30

How do you treat tension pneumothorax?

Answer 30

Needle Decompression

Wide bore needle - 2nd intercostal space at midclavicular line

Question 31

What is the costadiaphragmatic recess?

Answer 31

where the parietal pleura reflects forms a recess between the thoracic wall and diaphragm

Question 32

At what level does the trachea bifurcate?

Answer 32

T4/5

Question 33

Where are the horizontal and oblique fissures of the right lung?

Answer 33

Horizontal - 4th CC

Oblique - T3 Spinous Process to 6th cc anteriorly

Question 34

Where would you auscultate the upper, middle and inferior lobe?

Answer 34

Upper - anterior
Inferior - posterior
Middle - axillary lines (Breast tissue and pec major in the way at the front)

Question 35

What nerve does the revised triangle of safety avoid?

Answer 35

Long thoracic n

Question 36

Which bronchus is more vertical and wider?

Answer 36

R side - aspirate food

Question 37

Can bronchopulmonary segments be resected?

Answer 37

Yes - Smallest functionally independent region of lung that can be resected without affecting other regions
have own blood and air supply

Question 38

What are the walls of trachea supported by?

Answer 38

C - shaped cartilage

hyaline cartilage

Question 39

Describe the lymphatic drainage of the lungs.

Answer 39

Majority of lymphatic drainage is to right lymphatic duct / subclavian vein
Left upper lobe - Thoracic duct / left subclavian vein