Anatomy of Breathing Flashcards
What are the components of the upper respiratory tract?
* The right and left nasal cavities
* The oral cavity
* The naso-, oro- & laryngo- pharynx
* The larynx (sometimes classed as LRT)
What are the components of the lower respiratory tract?
* Trachea
* Right and left main bronchi
* Lobar bronchi
* Segmental bronchi
* Bronchioles
* Alveoli
At what point does the larynx become the trachea?
At level of C6 vertebra
At what point does pharynx become the oesophagus?
At level C6 vertebra
Where can the trachea be palpated?
The jugular notch of the manubrium
Where is the isthmus of the thyroid gland located?
Anterior to tracheal cartilages (rings) 2, 3 and 4
What is the Isthmus of the thyroid gland?
Where right and left sides of thyroid connect
Where is the thorax located?
Between the neck (above) and abdomen (below)
What 2 components is the thorax split into?
* Chest walls
* Chest cavity
What is the function of the chest walls?
* Protects the heart and lungs
* Makes movements of breathing
* Breast tissue - lactation
Where is the chest cavity located?
Within the chest walls of the thorax
What is the chest cavity composed of?
* Contains vital organs (viscera)
* Contains major vessels and nerves
* Consists of the mediastinum and the right and left pleural cavities
List the layers of the chest wall from superficial to deep
* Skin
* Fascia (superficial and deep)
* Skeletal muscle
* Bone/joints
* Parietal pleura - deepest layer
Where are the lungs located?
Inside right and left pleural cavities
What surrounds the pleural cavities?
Walls called pleura
Describe the growth of the lungs during embryonic development
Lungs will grow and push into the pleural cavity but will not enter it
What are the 2 types of pleura?
* Parietal - touches body wall structures (diaphragm and thoracic wall) * Visceral - touches lung
What is located between visceral and parietal pleural membranes?
Pleural fluid
Why do parietal and visceral pleura touch?
Due to surface tension - forces visceral and parietal pleura to stick to one another
What area do lobar bronchi supply with air?
Lung lobes Right lung - superior, middle, inferior lobes Left lung - superior and inferior lobes
What separates lung lobes?
Fissures
What is the area of lung lobe that each one of the segmental bronchi supply with air?
Bronchopulmonary segment
How many bronchopulmonary segments does each lung have?
10
How many lobes does each lung have?
5 lobes total Right lung - 3 lobes (superior lobe, inferior lobe, middle lobe) Left lung - 2 lobes (superior and inferior)
How many segmental bronchi does each lung have?
10 - one for each bronchopulmonary segment
What is the lingula?
Located on the left lung - “tongue” of superior lobe
How many pairs of ribs does the thoracic skeleton have?
12
* True ribs: 1-7 (attach via their costal cartilage to sternum)
* False ribs: 8-10 (attach via costal cartilage above to sternum) * Floating ribs: 11 & 12 (no attachment to sternum)
Label the diagram from A - J
A - Clavicle
B - Scapula
C - Sternal Angle
D - Intercostal space
E - Costal margin
F - Costal cartilage
G - Xyphoid process
H - Body of sternum
I - Manubrium
J - Jugular notch
Label structures from A - E
A - The head of the rib
B - The rib tubercle
C - The bodyshaft of the rib
D - Rib angle
E - The costal groove
Which areas of the rib articulate with the vertebrae?
The head and tubercle of the rib
What does the costal groove allow the passage of?
Neurovascular bundle - intercostal nerve, artery and vein
Which area of rib articulates with sternum?
Anterior end of rib - articulates with lateral aspect of sternum
Which vertebrae will the head of rib 2 articulate with?
Rib 2 will predominently articulate with the transverse process of T2 but will also articulate with the vertebrae above
How many vertebrae does the head of the rib articulate with?
2 - the tubercle articulats with only one vertebra
Name the the joints and structures labelled A - E
A - Sternum
B - Costal cartilages
C - Costal margin
D - Costocondral joints
E - Sternocostal joints
Name the labelled joint
Costovertebral joint
Name the 3 layers of skeletal muscle located betwen the ribs and within the intercostal spaces
* External intercostal muscles
* Internal intercostal muscles
* Innermost intercostal muscles
(in order from superficial to deep)
What is the function of the external, internal and innermost intercostal muscles?
They make the chest wall expand during breathing by elevating ribs and pushing them outwards
What is the diaphragm?
A skeletal muscle important in breathing
How many pairs of intercostal spaces are there?
11 pairs
What is the nerve in the NVB found in intercostal spaces?
Anterior ramus of spinal nerve (intercostal nerve)
Name the artery and vein that supplies/drains blood from the anterior intercostal space
* Internal thoracic artery
* Internal thoracic vein
What are the branches from the thoracic aorta’s anterior surface called?
Bronchial arteries
What is the function of bronchial arteries?
Supply arterial blood to lung tissue
What are the bilateral branches on posterior surface of thoracic aorta called?
Intercostal arteries
What is the function of intercostal arteries?
Supply the chest wall
What structures does diaphragm form?
* Forms floor of the chest cavity
* Roof of the abdominal cavity
Why does diaphargm have “openings”?
To permit structures to pass between the chest cavity and abdominal cavity
What is unusual about the structure of the diaphragm?
It has a central tendon
Diaphragm arranged as right and left domes. Which of the domes is superior?
The right dome - due to presence of liver inferiorly
Name the 3 areas the diaphragm attaches peripherally to
* The sternum
* The lower 6 ribs
* L1, L2 & L3 vertebral bodies
Which nerve supplies the muscular part of the diaphragm?
Phrenic nerve
From which spinal nerves does the phrenic nerve leave the spinal cord?
C3, 4 and 5 anterior rami
What are the phrenic nerves?
The combined anterior rami of cervical spinal nerves C3, 4 & 5
“C3, 4, 5 keeps the diaphragm alive”
Where are phrenic nerves found in the neck?
In the neck on the anterior surface of scalenus anterior muscle
Where are phrenic nerves found in the chest (thorax)?
Found in the chest descending over lateral aspects of the heart
What is the function of the phrenic nerves?
* Supply somatic sensory and sympathetic axons to diaphragm and fibrous pericardium
* Supply somatic motor axons to the diaphragm
What is the fucntion of the diaphragm in inspiration?
Contracts (and descends) and increases vertical dimensions of thorax
What is the function of intercostal muscles in inspiration?
Contract and elevate ribs, increasing dimensions of thorax anteriorly and laterally
How do the lungs expand if they are not attached to thoracic wall?
Thoracic wall expands vertically, anteriorly and laterally due to contraction of diaphragm and intercostal muscles
Parietal and visceral pleura stuck together due to surface tension, when parietal pleura moves out, visceral pleura and lungs move with it resulting in expansion of the lungs
What is the function of the pleural cavity in inspiration?
It acts as a “vacuum”
How does expansion of the lungs allow air flow?
It creates negative pressure inside the lungs and so air follows pressure gradient into lungs
How does air flow out of lungs?
Elastic tissue of lungs recoils
What are the 4 quadrants of the female breast?
Superolateral, superomedial, inferolateral, inferomedial quadrant
Which breast quadrant has axillary tail?
Superolateral quadrant (breast tissue extends into armpit)
Which fascia is breast suspended from?
Pectoral fascia (deep fascia)
Which vein drains the breast tissue?
Internal thoracic vein
What is the arterial blood supply to breast tissue?
Internal thoracic artery
Descrie lymph drainage from lateral quadrants of breast tissue
Unilateral drainage to axillary nodes
Describe lymph drainage of breast tissue from medial quadrants
Bilateral drainage from medial quadrants to parasternal nodes
Where is the sternal angle located?
At the level of rib 2
Name structures labelled A - H
A - Calvicle
B - Deltoid
C - Cephalic vein (in delto-pectoral groove)
D - Pectoralis major
E - Sensory nerves
F - Deep fascia
G - Superficial fascia (adipose tissue)
H - Skin
Name structures labelled A - D
A - Long thoracic nerve (supplies serratus anterior)
B - Latissimus dorsi
C - Seratus anterior (anchors scapula to ribs)
D - Pectoralis major
What is the function of the serratus anterior?
Anchors scapula to ribs
What nerve supplies the serratus anterior?
Long thoracic nerve
Normally, nerves supplying muscles are located in the deep surface. Where is the long thoracic nerve located?
Superficial surface
What problems can be caused by long thoracic nerve been located on the superficial surface?
Can be compressed easily, temporarily impairing its function. Results in “winged scapula” as serratus anterior no longer anchors scapula to thoracic cage (ribs)
What is latisimus dorsi?
An abductor muscle
Name the structures labelled A - I
A - Subclavian artery and vein
B - Internal thoracic artery and veins
C - Anterior intercostal vein
D - Anterior intercostal artery
E - Intercostal nerve
F - Intercostal muscles
G - Ribs
H - Deep surface of sternum
I - Deep surface of ribs
Name the 4 sub-divisons of the parietal pleura
* Cervical parietal pleura
* Costal parietal pleura
* Mediastinal parietal pleura
* Diaphragmatic parietal pleura
What is the most inferior (dependent) part of the pleural cavity when in upright position?
Costodiaphragmatic recess
Where is the costodiaphragmatic recess located?
Between the diaphragmatic parietal pleura and the costal parietal pleura
What is the most inferior region of the costodiaphragmatic recess?
Costophrenic angle
What are the problems associated with costodiaphragmatic recess being most dependent part of pleural cavity?
Abnormal fluid in cavity drains into recess - can cause pleural effusion or haemothorax
What can be seen from a CXR (chest x-ray) where there is a build-up of fluid in costodiaphragmatic recess?
“Blunting of the angles” and a visible fluid level
What are the structures of the root of the lung (Hila)?
* 1 main bronchus
* 1 pulmonary artery
* 2 pulmonary veins
* Lymphatics
* Visceral afferents
* Sympathetic nerves
* Parasympathetic nerves
Name structures A and B
A - Horizontal fissure (right lung only!)
B - Oblique fissure
Name structures of right hilum labelled A - D
A - main bronchi (hyaline cartilage in walls)
B - Pulmonary arteries
C - Pulmonary lymph nodes
D - Pulmonary veins
What structures cause depression on surface of right lung?
Heart, diaphragm and veins (SVC and azygous)
Name the structures of the left hilum labelled A - D
A - Main bronchi (hyaline cartilage in walls)
B - Pulmonary lymph nodes (black)
C - Pulmonary veins
D - Pulmonary artery
What structures cause depression on surface of left lung?
Arch of aorta
What is auscultation?
Listening to sound of air moving through the larynx
What does normal breathing sound like via stethoscope?
Rustling in nature
What structures must you auscultate?
* All 5 lobes
* The apices
* The bases
Where would you position stethoscope to listen to apex of the lung?
Superior to medial 1/3rd of clavicle
Where would you position stethoscope to auscultate the middle lobe?
Between ribs 4 and 6 in mid-clavicular and mid-axillary lines
Where is the horizontal fissure located?
Follows right rib 4
Where are oblique fissures located?
At level of ribs 6 anteriorly
Rise to T3 vertebral level posteriorly
Where would you position stethoscope to listen to the lung base (most dependent part of inferior lobe)?
Scapular line (passes vertically through inferior angle of scapula) at T11 vertebral level
