Mechanisms of ventilation

Question 1

What is the upper tract of the respiratory system

Answer 1

nasal cavity, pharynx, larynx

Question 2

What is the lower tract of the respiratory system

Answer 2

trachea downwards

Question 3

What keeps the trachea open at all times

Answer 3

rings of cartilage

Question 4

Right lung structure

Answer 4

3 lobes: superior, middle, inferior

2 fissures: horizontal, oblique

Question 5

Left lung structure

Answer 5

2 lobes: superior, inferior

1 fissure: oblique

Question 6

Difference between right and left bronchus

Answer 6

left is shorter, more horizontal and wider

Question 7

Respiratory tract from nose to trachea

Answer 7

nasal cavity
superior an dinferior concha
opening of pharyngotympanic tube
Pharynx: naso, oro, laryngo
epiglottis
larynx
trachea                                             (oesophagus)

Question 8

Epiglottis role

Answer 8

covers the laryngeal inlet so food passes into the oesophagus and not the trachea

Question 9

How do we breathe?

Answer 9

diaphragm contracts and flattens, increasing thoracic volume and decreasing pressure
air is drawn into the lungs from outside
air passes into terminal bronchioles/alveoli to oxygenate blood
diaphragm relaxes, lungs recoil, thoracic volume decreases, intrathoracic pressure increases and air expelled

Question 10

What is the most important muscle in respiration?

Answer 10

diaphragm

Question 11

What innervates the diaphragm?

Answer 11

phrenic nerve (C3-5)

Question 12

Attachments of diaphragm

Answer 12

anterior: xiphisternum and costal margin
lateral: ribs 6-12
posterior: T12

Question 13

Accessory muscles of respiration

Answer 13

intercostal muscles
sternocleidomastoid
scalenus anterior
pecs
trapezius

Question 14

How do the icms assist respiration?

Answer 14

contraction of obliquely angled external and internal fibres raises each rib toward the rib above to rasie ribcage
innermost and inner depresses each rib to the rib below, lowering the rib cage

Question 15

How does the sternocleidomastoid muscle assist respiration?

Answer 15

attaches to manubrium and clavicle and mastoid process on the skull
raises sternum

Question 16

How does scalenus anterior assist respiration?

Answer 16

prevent rib 1 and 2 from descending

Question 17

How does do the pecs and trapezius assist respiration?

Answer 17

fix the pectoral girdle to raise rib cage

Question 18

Movement of the ribs and sternum when breathing

Answer 18

sternum: pump
ribs: bucket handle
lower ribs expand ribcage most for sternum to move

Question 19

Where are the apex of the lungs and what are they covered by?

Answer 19

above 1st rib

covered by suprapleural membrane (so lungs don’t dip in and out of neck)

Question 20

What allows the thoracic cavity and lungs to expand?

Answer 20

surface tension between the parietal and visceral pleura

Question 21

Difference between adults and babies breathing

Answer 21

babies can only breathe via abdominal breathing
newborn ribs more horizontal - no pump/bucket movement
weak icms, use only diaphragm

Question 22

Dangers of relying on the diaphragm for breathing

Answer 22

high risk for respiratory failure if it is unable to contract

Question 23

Difference between adults and children breathing

Answer 23

nasal breathers until 4-6 wks
shorter neck and narrower airways
larger tongue
smaller lung capacity, underdeveloped chest muscles
higher respiratory rate

Question 24

Dangers of breathing as a child

Answer 24

narrower airways: more susceptible to blocked airways and respiratory distress
larger tongue: obstruct when unconscious

Question 25

Where is the costodiaphragmatic recess and what is its clinical relevance?

Answer 25

bottom of right lung

where fluid in the cavity gathers first

Question 26

Where is the costomediastinal recess?

Answer 26

cardiac notch

Question 27

What is the carina?

Answer 27

ridge at the point of bifurcation in the trachea to form left and right bronchi

Question 28

Main types of respiratory distress

Answer 28

1. neonatal respiratory distress syndrome: premature babies
2. acute respiratory distress syndrome: fluid/proteins leak from blood vessels into alveoli (most common cause is infection eg pneumonia)

Question 29

Symptoms of respiratory distress

Answer 29

blue coloured extremities, rapid and shallow breathing, rapid heart rate
use of accessory muscles at rest can be a sign

Question 30

Types of pneumothorax

Answer 30

1. non-tension

2. tension

Question 31

Non-tension pneumothorax

Answer 31

hole in pleural cavity and therefore air can enter and leave

can partially expand, not full capacity

Question 32

Tension pneumothorax

Answer 32

more severe, hole covered by flap of tissue
lungs can’t expand, air can enter but not escape
mediastinum and heart deviated - arrhythmia and heart pain

Question 33

Emphysema

Answer 33

type of COPD
inflammatory response, destruction of alveoli
over-inflated alveoli have ineffective gas exchange
on x-ray: hardly any difference between expiration and inspiration