2 - Anatomy of the Respiratory System 2

Question 1

Where is the parietal and visceral pleura?

Answer 1

- Parietal: inside of each hemi thorax and it is continuous with the hilum

- Visceral: between lobes of the lung into the oblique and horizontal fissures

Lungs don’t completely fill the pleural cavity formed and parietal pleura forms gutter called costodiaphragmatic recess

Question 2

What is the function of the pleura?

Answer 2

Contains pleural fluid. Surface tension forces between pleural fluid creates a seal so when thorax expands, lungs expand with it

Question 3

What is the bronchial tree and the route of the trachea?

Distinguish by names of each parts of the bronchi
And also the importance of the sternal angle

Answer 3

Trachea from lower border of cricoid cartilage (after pharynx) and terminates into primary bronchi at level of sternal angle

The sternal angle is an important clinical landmark for identifying many other anatomical points: It marks the point at which the costal cartilages of the second rib articulate with the sternum.

Question 4

What is a bronchopulmonary segment?

Answer 4

- Area of lung supplied by a segmental(tertiary)bronchus and accompanying segmental branch of the pulmonary artery. Drained by segmental pulmonary vein.

• Pyramid shaped with apex towards segmental bronchus

Question 5

Where are inhaled foreign bodies most likely to lodge themselves?

Answer 5

Right primary bronchus as it is wider, shorter and more vertical than the left

Question 6

What is a bronchoscopy?

Answer 6

Used to see trachea, carina, main bronchi, lobar bronchi and start of segmental bronchi. Used for diagnosis of bronchial carcinoma and to obtain biopsy

Question 7

What is the difference between the conduction and respiratory zones?

Answer 7

Conducting: 1-16 divisions, from trachea up to an including terminal bronchioles. No gas exchange

Respiratory: Next 7 divisions, include respiratory bronchioles, alveolae ducts and alveolar sacs

Altogether 23 divisions

Question 8

What is the difference between the right and the left lung?

Answer 8

• Fissures can fill with fluid
• Left only has two lobes

Question 9

What are the different surfaces of the lungs?

Answer 9

Apex: above level of 1st rib into root of the neck

Base: rests on each hemi-diaphragm

Mediastinal surface: hilum. Left adjacent to heart, aortic arch, descending aorta, oesophagus, phrenic nerve, vagus nerve and recurrent laryngeal. Rgith adjacent to SVC, azygous, right atrium, oesophagus, phrenic and vagus nerve. BOTH sympathetic trunk posteriorly

Question 10

What can tumours in the apex of the lung cause?

Answer 10

Neurological and vascular issues with the upper limb as the subclavian vessels run near the apex of the lung

Question 11

What are some causes of a pneumothorax?

Answer 11

• Cannulation of subclavian vessels
• Stab wound to lower neck

(collapsed lung due to air getting between lung and chest wall)

Question 12

What are some mediastinal structures that can be damaged by lung cancers, enlarged hilar lymph nodes or aortic aneurysms?

Answer 12

Question 13

What are the vertical lines on the thoracic wall that we can use for surface marking?

Answer 13

Question 14

How can we identify the rib numbers?

Answer 14

Find the jugular notch then palpate down until sternal angle found. This is rib 2, then count downwards

Sternal angle is between the manubrium and the sternal body

Question 15

How can we surface visualise the lobes of the lungs?

Answer 15

• Oblique fissure: spinous processes of T2 to 6th costal cartilage. Medial border of scapula when arm adducted
• Horizontal fissure: mid axillary line to 4th rib

Question 16

What lobes are being ausculated in each instance here?

Answer 16

Question 17

What is the surface marking of the pleura and the lungs?

Answer 17

- Pleura: rib 8 (MCL), rib 10 (mid axillary), rib 12 (scapular line)

- Lungs: rib 6 (MCL), rib 8 (mid axillary), rib 10 (scapular)

Question 18

How can you percuss for the liver and how would this change in COPD?

Answer 18

• Dome of right hemi-diaphragm and upper border of liver at level of 5th rib so normal lung resonance is replaced by dullnes from 5th ICS down
• In COPD air trapping and over inflation of lungs pushes diaphragm down so percussion note still resonant to 6/7/8th ICS

Question 19

What can Horner’s syndrome be a sign of?

Answer 19

Could be a sign of apical lung cancer that is affecting the brachial plexus and sympathetic chaing

Loss of sweat on face
Partially drooping upper eyelid
Small pupil

Question 20

What is flail chest?

Answer 20

• Type of rib fracture
• Chest pain and shortness of breath
• Mediastinum shifts with each breath

Question 21

What is a pleural effusion?

Answer 21

Collection of fluid in pleural cavity and the fluid collects in the costodiaphragmatic space in upright position so blunting of costo-phrenic angle on x-ray

Question 22

Where does neurovasculature run in relation to the ribs?

Answer 22

Costal groove so always put chest drain in at upper border of rib to avoid injury

Question 23

What is the parietal pleura innervated by?

Answer 23

Thoracic nerves, painful if hit!! Visceral not painful when irritated

Question 24

What structures could be damaged in this case?

Answer 24

• Brachial plexus
• Lung apex (pneumothorax)
• Thoracic duct
• CCA
• IJV
• Subclavians

Question 25

How can you identify the phrenic and vagal nerves in saggital cross section?

Answer 25

Phrenic nerve lies anterior to the hilum on the fibrous pericardium; vagus passes posterior to the hilum

Question 26

What clinical signs would you expect if the superior vena cava was compressed by local spread of a lung tumour?

Answer 26

o Swelling of the arms, face and neck, o Dilated veins over the arms and chest o Elevated Jugular venous pressure, o Papilloedema

Question 27

How do you resolve asphyxiaton in a choking child?

Answer 27

o Lean the child forwards and carry out up to 5 back blows; if not successful try abdominal thrusts (the Heimlich manoeuvre). o Call an ambulance.

Question 28

A 70 year old man has right lower lobe pneumonia, where would you auscultate for this?

Answer 28

Right lower chest posteriorly

Question 29

What is the blood supply to the visceral and parietal pleura?

Answer 29

**- Visceral:** bronchial arteries **- Parietal:** intercostal arteries

Question 30

What are the different cell types in the respiratory tract?

Answer 30

Question 31

What is this x-ray showing?

Answer 31

Calcification of trachea which occurs with ageing. Dont forget fibroelastic membrane behind cartilage contains trachealis muscle.

Question 32

What is the difference in structure between a bronchiole and a bronchus?

Answer 32

Alveoli keep the lumen open in bronchioles. Bronchioles also have smooth muscle that can cause issues in asthma as no cartilage to hold it open

Question 33

Is inspiration or expiration harder in asthmatic attacks?

Answer 33

Expiration as during expiration bronchial walls no longer held open by surrounding alveoli

Question 34

Label this histological section of an alveolar lobule.

Answer 34

Question 35

What is this cross section of the alveoli showing?

Answer 35

**Emphysema** - Smoking or A1-Antitrypsin deficiency - Alveolar walls normally hold bronchioles open to allow air to leave lungs on exhalation but these walls damaged so bronchioles collapse and air becomes trapped in alveoli so difficult to empty lungs

Question 36

What is this histological section of the lung showing? What organism likely

Answer 36

Acute pneumonia - inflammation of the lung due to bacteria so lung consolidates

Question 37

How is the lung protected from inhaled particles?

Answer 37

Inhaled particles (between about 5 – 8 μm) deposited on mucus layer and **muco- ciliary escalator** to the oropharynx where they are swallowed. Larger Particles (\>8 μm or so) are deposited on the mucus layer lining the nose and pharyngeal walls; these are swept to the oropharynx where they are **swallowed**. Smaller particles (\< 5 μm or so) reach the respiratory bronchioles and alveoli - **alveolar macrophages**.