Basic structure of the airways

Question 1

What might breathlessness be due to?

Answer 1

• Lung disease
• Heart disease
• Pulmonary vascular disease
• Neuromuscular disease ( e.g diaphragm weakness)
• systemic disorders (e.g. anaemia, hyperthyroidism, obesity)

Question 2

Describe the role of the nasal cavities.

Answer 2

The nasal cavity exists to warm the air before it goes down into the lungs as cold air is an irritant.

Question 3

Label the nasal cavity nerves:

Answer 3

Olfactory nerves.
Nasopalatine nerve (V2).
Medial internal nasal br of ant ethmoidal nerve (V1).

Question 4

How many ridges exist in the paranasal sinuses and how many sinuses

Answer 4

There are 3 major ridges known as the choncha – the inferior, middle and superior.

Four Paranasal Sinuses: Frontal, Maxillary, Ethmoid, Sphenoid

Question 5

where is the sphenoidal sinus associated with?

Answer 5

The sphenoidal sinus sits just below the sella turcica (pituitary gland bone)

Question 6

why is it difficult to clear infection in the body?

Answer 6

In the maxilliary sinus, the meatus that exits from it is located at the superior aspect which makes drainage difficult so this makes it difficult for the body to clear infection.

Question 7

what is close to the teeth?

Answer 7

The maxilliary sinus

Question 8

what are the functions of the paranasal sinus?

Answer 8

1. Lightens the skull by increasing strength to weight ratio.
2. Acts as an insulator by trapping warm air.
3. Acts as a resonating chamber for the voice.
4. Acts as a crumple zone to protect the brain in severe trauma.

Question 9

What are the three parts of the pharynx and where are they found?

Answer 9

Nasopharynx - behind the nasal cavities
Oropharynx - posterior to the tongue, consists of lymphoid tissue
Laryngopharynx - after the epiglottis

Question 10

what is the only bone found in the larynx?

Answer 10

The hyoid bone

Question 11

Where are tracheostomies performed?

Answer 11

It is performed in the cricothyroid ligament.

Question 12

what controls pitch and volume?

Answer 12

It is controlled by the vocal ligaments (vocal folds)

Question 13

what is the trachea made of?

Answer 13

The trachea is made up of around 20 rings of cartilage in horseshoe shapes into which the oesophagus can expand during peristalsis.

Question 14

Describe the arrangement of the trachea

Answer 14

The primary bronchus go into the lungs and then secondary bronchi are located in each lobe.
Tertiary bronchus go into bronchopulmonary segments.

Question 15

How are the bronchi held?

Answer 15

All of the bronchi are held open by cartilage to some degree, the bronchioles are supported by smooth muscle cells

Question 16

what is the carina and where does this occur?

Answer 16

The Corina is the name for the located of the bifurcation of the trachea into the bronchi. This occurs at the 2nd CC or T4/T5.

Question 17

How many lungs in right and left lung?

Answer 17

Right= 3
Left= 2

Question 18

what can you see in the right lung?

Answer 18

Right Lung (left side, 3 lobes):

o The grooves are for the azygous vein and oesophagus.

o In the hilum, the pulmonary arteries (blue) and veins (red) can be seen alongside the bronchi and lymph nodes.

Question 19

What can you see in the left lung?

Say what is the partial pressure of the oxygen in air and blood

Answer 19

Left Lung (right side, 2 lobes):

o The arch of the aorta groove and the associated common carotid and subclavian can be seen.

-pO2 Air = 100mmHg, pO2 Blood = 40mmHg.

Question 20

What’s inside the diaphragm and why?

Answer 20

The white part must be a tendon otherwise when the diaphragm contracts, the IVC would be crushed and we would die.

Question 21

At which level does oesophagus pierce the diaphragm?

Answer 21

T10

Question 22

where does the phrenic nerve originate at and what does it innervate?

Answer 22

The phrenic nerve originates at C3, 4, 5 and provides innervation to the diaphragm; without it, we would die as we wouldn’t breathe.

Question 23

where is the phrenic nerve and vagus nerve?

Answer 23

The vagus nerve passes anteriorly to the heart, the phrenic nerve runs posteriorly to the heart.

Question 24

What are the bony structures underlying the epithelial layer on the lateral side of the nasal cavities called?

Answer 24

Conchae

Question 25

Describe the resistance of the nasal cavities and the implications for exercise.

Answer 25

High resistance - when exercising, breathing is mainly done through the mouth because that is a path of lower resistance and more water is lost

Question 26

What are the paranasal sinuses? What is their role?

Answer 26

4 sets of blind-ended out-pocketings of the lateral walls of the nasal cavities
Four Paranasal Sinuses: Frontal, Maxillary, Ethmoid, Sphenoid
They reduce the weight of the facial bones, provide a crumple zone for facial trauma, act as resonators for the voice and insulate sensitive structures from the rapid temperature fluctuations in the nasal cavities.

Question 27

What is the larynx?

Answer 27

Cartilaginous structure that is supported from the roof of the mouth from the hyoid bone

Question 28

What structure is attached to the vocal ligaments which open and close entry to the larynx?

Answer 28

Arytenoid cartilage

Question 29

How many cartilage rings are around the trachea?

Answer 29

Around 20

Question 30

Describe the anterior and posterior lining of the trachea.

Answer 30

Anterior lining is epithelium

Posterior lining has trachealis muscle - this is needed for swallowing

Question 31

Describe the changes in number of cartilage rings and smooth muscle that changes with branching of the bronchi.

Answer 31

Number of cartilage rings decreases

Amount of smooth muscle increases