Respiratory Anatomy Flashcards
Where does the respiratory system develop from?
As an outpouch of the primitive gut tube
What is important to remember about the floor of the nasal cavity?
The floor of the nasal cavity lies in a horizontal plane
Name some of the functions of the nasal cavity
- Induces tubulent air flow via nasal conchae
- Warm and moisten inspired air
- Recover water from expired air
- speech production
- olfaction
what are the functions of the nasal cavity all reliant on?
A large surface area
What are paranasal sinuses?
Air filled spaced within the head that minimise the weight of the head
Identifiy the structures of this cross section of the upper airway
Name the divisions of the conducting airways in order
- Trachea
- Primary (main) bronchi - Right and Left
- Secondary (lobar) bronchi- 3 Right and 2 Left
- Tertiary (segmental) bronchi
- Bronchioles
- Terminal bronchioles
How does the chest wall move during inspiration?
Bucket handle like movement i.e. Elevates laterally
Desribe the movement of the sternum during inspiration
Pump handle movement i.e Up and Anteriorally
to increase the anterior posterior dimension
In which direction does the diaphragm move during inspiration?
The diaphragm moves down and flattens
During quiet respiration it does most of the work
With regards to pressure, how do the movement of the ribs cause movement of air into the lungs?
Interpleural pressure drops as alveolar pressure must be lower than atmospheric pressure for air to enter alveoli
Which nerves innervate the diaphragm? What is their origin?
Left and Right Phrenic nerves
C3, C4, C5
At what rib levels does the dome fo the diaphragm lie?
- Right = level of 5th rib
- Left = level of 5th intercostal space
What are the layers of intercostal muscle, from superficial to deep?
- External intercostal muscles - fibres run downwards and anterioraly
- Internal inrercostal muscles- fibres run downwards and posterioraly
- Innermost intercostal muscles- fibres run downwards and posterioraly
When are each of the intercostal muscles used during respiration?
- External intercostal muscles - 30% of quiet respiration
- Internal inrercostal muscles- forced expiration
- Innermost intercostal muscles- forced expiration
What is contained within the neurovasculature bundles around the ribs and why is this clinically relevant for chest drains?
- Intercostal arteries, veins and nerves
- Major and minor bundles - major located below rib, minor located above rib
When performing chest drains always go above the rib
Which 3 structures penetrate the diaphragm and at what vertebral level?
- Vena Cava T8
- Oesophagus T10
- Aortic hiatus T12
What is the azygous drainage system?
Venous drainage system responsible for draining the thoracic wall and upper lumbar region via the lumbar veins and posterior intercostal veins
i.e. drains intercostal spaces even at level of the heart
Describe the lobes of the lungs and how they are divided
- Right lung has 3 lobes (upper, middle and lower)
- Upper and middle split by transverse fissure
- Middle and lower split by oblique fissure
- Left lung has 2 lobes (upper and lower) divided by the oblique fissure
Which bronchus are inhaled objects more likely to go down and why?
- Right Bronchus
- Wider, Shorter and Straighter angle than left
What is the angle of Louis?
- Sternal Angle at the level of T4/T5 intervertebral disc
- Separates the mediastinum into superior and inferior
How is the inferior mediastinum divided?
- Anterior ► mainly fat or thymus (in children)
- Middle ► area of the heart
- Posterior ►Aorta, Oesophagus, Azygous Vein, Thoracic Duct
What is the costo-diaphragmic recess?
A peripheral gutter around the edge of the diaphragm where only the parietal pleura extends
i.e. the lungs do not fill this space of the thorax
Describe the blood supply of the lungs
The lungs have dual blood supply
- Bronchial arteries
- Pulmonary arteries
