Respiratory System Flashcards
What does the thoracic wall enclose?
Right and left pleural cavities (containing the lungs
What is located between the lungs?
Mediastinum (including the heart)
What kind of cavity is the pleural cavity?
Closed sac
What is the function of the thoracic wall
To protect the content of its sacs and permit the movement associated with respiration
What does the thoracic wall comprise of anteriorly?
Sternum
What does the thoracic wall comprise of posteriorly?
Vertebrae T1-T12
What does the thoracic wall comprise of laterally?
ribs 1 - 12
What bones articulate with the manubrium ai its superolateral angles?
First ribs
What is the name given to the joint between the superolateral angle of the manubrium and the first ribs?
Sternocostal joint
What type of joint is the sternocostal joint?
Cartilaginous (synchondroses)
What is the name given to the notch formed by the superior border of the manubrium?
Jugular notch
At what vertebral level is the xiphoid process located?
T10
At what vertebral level is the sternomanubrial joint located?
T4
What component part of the sternum do the facets for the 2nd costal cartilage articulate?
Manubrium
What are the typical ribs?
Ribs 3-9
The head of rib 5 articulates with the bodies of which vertebrae?
T4 & T5
Where does the tubercle of a rib articulate?
Transverse costal facet (transverse process) of vertebrae.
What structures lie in the costal grove of a rib?
Intercostal vein, intercostal artery, intercostal nerve
What ribs are true ribs?
Ribs 1 -7
What ribs are false ribs?
Ribs 8 - 10
What ribs are floating ribs?
Ribs 11 - 12
Why is the 1st rib an atypical rib?
It is short, wide and flat from top to bottom, and it articulates with only a single vertebrae (T1) and it onyl has one articular facet.
What does the 1st rib form?
It forms one of the superior boundaries of the bony thorax.
Where does the groove for the subclavian artery lie on the scalene tubercle?
Posterior
Where does the groove for the subclavian vein lie on the scalene tubercle?
Anterior
What attaches to the scalene tubercle?
The anterior scalene muscle of the neck (an accessory muscle in forced inspiration.)
What shape is the thoracic vertebrae?
Heart shaped
What part of the rib articulates with the demi-facets?
Head of the rib (one at the same level and one above)
What part of the rib articulates with the costal facet?
Tubercle of the rib (one on the same level)
A single typical rib articulates with how many vertebral bodies?
2 (same level and one above)
How many vertebral transverse process does a single rib articulate?
1 (same number as rib)
What happens when an extra cervical rib develops?
This can result in compression of the lower trunk of the brachial plexus, parasthaesia of
the medial side of the upper limb, and wasting of the small muscles of the hand.
Where does this extra cervical vertebrae develop?
Transverse process of C7
Which ribs are most commonly fractured and why?
Ribs 5 - 10 because they are more exposed and fixed.
What can a fractured rib cause?
They perforate the pleura resulting in a pneumothorax.
What is a pneumothorax accompanied by?
Severe localised pain mediated through the intercostal nerves located above and below and concomitant dyspnoea (difficulty in breathing)
What forms the superior thoracic aperture posteriorly?
Body of T1
What forms the superior thoracic aperture laterally?
Medial margin of the 1st rib
What forms the superior thoracic aperture anteriorly?
Manubrium
What forms the inferior thoracic aperture anteriorly?
Costal margins
What forms the inferior thoracic aperture laterally?
Distal tip of rib 11 and rib 12
What forms the inferior thoracic aperture posteriorly?
Body of T12
What closes of the inferior thoracic aperture?
Diaphragm
What is the thoracic inlet?
Superior thoracic aperture
What is the thoracic outlet?
Inferior thoracic aperture
Which costal cartilages form the costal margin?
7 - 10
Which costal cartilages form the subcostal angle?
7 - 10
Which costal cartilages are directly attached to the sternum?
1 - 7
Which costal cartilages are indirectly attached to the sternum through attachment to preceeding costal cartilages?
8 - 10
What makes up the thoracic cavity posteriorly?
T1 - 12
What bones make up the lateral side of the thorax?
12 ribs
What makes up the anterior aspect of the thorax?
Costal cartilages and sternum
What is thoracic outlet syndrome?
The brachial plexus (C5-T1), the subclavian artery and vein become compressed by structures such as tumours of the lung between the first rib and clavicle, as they enter the upper limb, with resultant limb clinical signs.
What muscle is primarily used for breathing in a new born?
Diaphragm
How are the rib angles positioned with respect to the spinous processes?
They are level
What is contained in the paired intercostal spaces?
- 3 layers of intercostal muscles, intercostal nerves and a posterior and anterior artery and vein.
What is the origin and insertion of the intercostal muscles?
Origin: inferior border of the rib above
Insertion: superior border of the rib below
What is the direction of the fibres of the external intercostal muscles?
Antero-medial
What is the direction of the fibres of the internal intercostal muscles?
Posteo-lateral
What does the number of each intercostal space accord with?
The number of the rib lying superior to it.
What number of rib accords with the number of intercostal nerve, artery and vein?
The rib above.
Where is the innermost intercostal muscle located?
Posteriorly behind the two ribs
In between which muscles do the intercostal vein, artery and nerves run?
They run between the internal intercostal muscle and the innermost intercostal muscle.
What is the most superficial intercostal muscle called?
External intercostal muscle
What is the intermediate intercostal muscle called?
Internal intercostal muscle
What is the deepest intercostal muscle called?
Innermost intercostal muscle
In which part of the rib is the neurovascular bundle lodged?
Costal groove
What can happen if the chest drain is inserted to close to the inferior border of the rib?
The intercostal nerve can be damaged
What is another function of the intercostal muscles other than contributing to the respiratory movements of the chest?
Preventing the lungs and the pleura from ballooning out between the ribs during the movement of the chest wall.
How do the external and internal intercostal muscles not occupy the entire length of the intercostal space?
They become aponeurotic at one end, called the intercostal membrane.
How much of the intercostal space does the innermost intercostal muscles fill?
Half, the other half is completed anteriorly by the transversus thoracis muscles and posteriorly by the subcostalis muscles
What does each structure forming the neurovascular bundle give of above each rib?
Small collateral branch
What is the normal location of a chest drain?
5th intercostal space in mid axillary line
Where in relation to the upper and lower borders of a rub do you think a chest drain needle should be inserted into the pleural cavity to avoid damaging the intercostal nerves?
Above the superior border
What are the tissues of the chest wall that a chest drain needle will need to pass from superficial to deep?
Skin
Superficial fascia
Deep fascia
External intercostal muscle
Internal intercostal muscle
Innermost intercostal muscle
Parietal pleura of the lung
Pleural cavity
(after this is visceral pleura then the lung which the needle should not reach)
What do dermatomes correspond with on the chest wall?
Intercostal spaces
What is a dermatome?
Area of skin supplied by a single spinal nerve
At the sternal angle, dermatome C4 lies immediately above T2 instead of C5, why is this?
C5 - T1 supplies the arms
What dermatome is overlying the sternal angle?
T2
What dermatome is overlying the nipple area?
T4
What dermatome is overlying the umbilicus?
T10
What dermatome is overlying the inguinal region?
L1
What is lymph?
Plasma that has leaked from the capillary beds due to high hydrostatic pressures.
What is the function of the lymphatic system?
Return lymph to the circulatory system, also plays a role in immunity and cancer spreas.
What organs dont have lymphatic drainage?
Cartilage, eyes, inner ear, brain and spinal cord
What are the main groups of lymph nodes?
Axillary Superficial and deep inguinal Pectoral Tracheobronchial Bronchomediastinal Lumbar/pelvic Superficial cervical and deep cervical
Where are the axillary lymph nodes?
Root of the upper limb
Where are the superficial and deep inguinal lymph nodes?
Root of the lower limb
Where are the pectoral lymph nodes?
Around the pectoralis major muscle
Where are the tracheobronchial lymph nodes?
Bifurcation of the trachea in the thorax
Where are bronchomediastinal lymph nodes?
The hilum of the lungs
Where are the lumbar/pelvic lymph nodes?
Around the root of the arteries in the abdomen and pelvis
Where are the superficial and deep cervical lymph nodes found?
Head and neck
How does lymphatic fluid get from the lymph nodes back to the venous circulation?
Efferent lymphatic vessels arise which lead to the thoracic duct or right lymphatic duct
Where do lymph nodes tend to be clustered?
Around large veins
Where do the axillary lymph nodes lie?
In relation to the axillary vein and its branches in the axilla.
What are examples of axillary node?
Anterior, posterior, apical, central and lateral groups.
What connects axillary nodes together?
Lymph channels
What is the composition of the breast?
Glandular surrounded by extensive adipose tissue.
Where does most of the breast lymph drain to?
anterior (pectoral) group of axillary lymph nodes
Where is the base (glandular part) of the breast located?
Between ribs 2 to 6 and between the lateral border of the sternum and the midaxillary line
What is the glandular part of the breast divided into?
16-20 lobes and smaller lobules
Where does the axillary tail of the breast penetrate?
Into the floor of the axilla
What are the 4 attachments of the diaphragm?
Lumbar vertebrae
Arcuate ligaments
Costal cartilages
Sternum
What are the 3 main openings of the diaphragm?
Caval hiatus
Oesephageal hiatus
Aortic Hiatus
What level is the vena cava opening at?
T8
What level is the oesophagus opening at?
T10
What level is the aortic hiatus at?
T12
What structures do the vena caval opening have?
Inferior vena cava and terminal branches of the phrenic nerve
What structures do the oesophageal opening have?
Oesophagus, right and left vagus nerves, Oesophageal branches of left gastric artery/vein.
What structures do the aortic hiatus have?
Aorta, thoracic duct and azygous vein
What do the hiatuses of the diaphragm permit?
They permit structures to pass through the abdomen and the thorax.
What are the main functions of the diaphragm?
Respiration and raising intra-abdominal pressure during coughing, vomiting and defecation.
Which dome of the diaphragm is more superior?
Right
Why is the right dome of the diaphragm more superior than the left?
Left needs to make more room for heart
What cardiac structure is firmly attached to the central tendon?
Fibrous pericardium
At which vetebrae are the left and right crura attached?
Left - L1 - L2
Right - L1 - L3
What is the crura of the diaphragm?
Tendinous structures that extend below the diaphragm to the vertebral column, forming a muscular tether for contraction.
Which membrane covers the superior surface of the diaphragm?
Parietal
When the diaphragm contracts, do the domes ascend or descend?
Descend
What is the shape of the central tendon?
Clover
What tendon is the diaphragm attached to?
Central tendon
What costal cartilages is the diaphragm attached to?
7 - 10
What part of the sternum is the diaphragm attached to?
Xiphoid process
What vertebrae is the diaphragm attached to?
L1 - L3
How do major and smaller structures pass through the diaphragm?
Major structures pass through the major hiatuses
Smaller structures can pass along with the major structures or pass through a minor hiatus by themselves
Through which part of the diaphragm does the inferior vena cava pass?
Tendinous
Why does the inferior vena cava pass through the tendinous and not muscular part of the diaphragm?
So it doesn’t contract and stop the blood flow
Why do the structures that pass through the diaphragm more anteriorly also pass through it at a higher vertebral level?
because of the dome shape of the diaphragm
What is hiatus hernia?
• Abnormal protrusion (herniation) of a structure into the thorax through a tear or weakness in the diaphragm caused by frequent hard coughing, heavy lifting or a number of other things
What type of supply does the diaphragm get?
• Motor and sensory supply on its left, right, superior and inferior parts
What type of supply does the phrenic nerve supply to the diaphragm?
Motor and sensory nerves
What type of supply does the lower intercostal nerve provide to the diaphragm?
• Sensory to the peripheral parts of the diaphragm (T7 - T12)
What are the spinal root values of the phrenic nerve?
• C3-5
What happens when there is damage to the spinal cord just above the phrenic nerve spinal roots?
• Paralysis of the diaphragm and the need for artificial ventilation.
Damage to the phrenic nerve can lead to which dome being damaged?
• Ipsilateral dome
How is respiratory function maintained when one lobe is paralysed?
• this is done by the intercostal muscles and nerves
When should penetrating wounds be suspected to cause damage to the diaphragm?
• Below the nipples (intercostal space 4) due to the upwards arching of the domes in quiet expiration to the rib 5 if not higher
What does the upper respiratory tract consist of?
• Nasal cavity, pharynx and larynx
Where is the URT located?
• head and neck
What is the larynx composed of?
• Set of carilages, membranes and ligaments
What does the larynx do?
- Produces sound from expired air
* Protect the inlet to the respiratory system
What is found superiorly to the larynx?
• hyoid bone
What is found inferiory to the larynx?
• Trachea
What is the larynx related to anteriorly?
Pharynx
What cartilage forms the laryngeal prominence?
• Thyroid cartilage
What structure prevents solids and liquids from entering the laryngeal inlet?
• Epiglottis
What cartilages are attached to the vocal cords?
• Arytenoid
What kinds of cartilage is all of the cartilage of the larynx?
• hyaline, except epiglotttis which is elastic
What kind of cartilage is the epiglottis?
• Elastic cartilage
What does the LRT consist of?
• trachea, bronchi, bronchioles and alveoli
Where is the LRT located?
• mostly in the thorax
What does the lower respiratory tract recieve its nerve innervation by?
- Sympathetic fibres originating in the upper thoracic spinal level via pulmonary plexuses located at the termination of the main bronchi
- Parasympathetic fibres from the vagus nerve
- both of the above are motor.
How does the lower respiratory tract recieve its arterial supply?
• Via the bronchial arteries arising from the thoracic aorta and intercostal arteries
What veins supply the lower respiratory tract?
• Bronchial veins drain to the azygos veinous system and accessory hemiazygous vein
Where does the venous supply from the lower respiratory tract drain to?
• Azygos venous system
What vertebrae levels does the trachea being and end?
- Begins at C6 (inferior to the cricoid cartilage)
* Ends at T4
What structure is present at T4?
• Sternal angle (carina)
What happens to the trachea at T4?
• Bifurcates in to the primary left and right brinchi
What vertebrae level does the trachea bifurcate into the left and right main bronchi?
• T4
How many hyaline cartilage rings are in the trachea?
• 16 - 20
What is the muscle called that completes the tracheal rings of cartilage?
• Trachealis
What is the final keel-shaped cartilage ring at the bifurcation of the trachea called?
• Carina
What is the tubular organ lying immediately posterior to the trachea?
• Oesophagus
What are the arteries called lying immediately lateral to the trachea in the neck?
• common carotid arteries
Where do the common carotid arteries in the neck lie relative to the trachea?
• Lateral
What is the nerve called lying immediately lateral to the trachea at both sides?
• Vagus nerve
Where does the vagus nerve lie relative to the trachea?
• Lateral at both sides
What are the groves called that lie between the trachea and oesophagus on both sides?
• Trachea-oesophageal grooves
What lodges into the Trachea-oesophageal grooves?
• Recurret laryngeal nerve
What do the recurrent laryngeal nerves supply?
• they supply motor and sensory innervation to the larynx
Which of the two main bronchi is shorter, wider and more vertical?
• Right
In which bronchi are accidentally aspirated objects more likely to pass?
• right because it is shorter and less wide
What two main arteries arch above the left bronchus?
• Aorta and pulmonary artery
Above which bronchus does the aorta and pulmonary artery arch above?
• Left
What is the main difference between the branches of the left and right bronchus?
- Left main bronchus enters the lung before giving off branches
- Right main bronchus gives off a superior branch just before entering the lung
Once the right bronchus splits just before entering the lung, what is the superior and inferior component called?
- Superior - superior lobar bronchus
* Inferior - hyparterial bronchus
What do bronchi lose as they branch?
• cartilage, cilia, glands and smooth muscle
What increases in bronchi as they branch?
• Elastic fibre content
Where does lymph draining from the trachea, bronchi and lungs go to?
• Tracheobronchial lymph nodes
Where are the tracheobronchial lymph nodes relative to the bronchi?
• Lie alongside as well as in the cleft between the two main bronchi
Where do the traheobronchail lymph nodes drain to?
• Thoracic duct or right lymohatic duct
What is the role of tracheobronchial lymph nodes?
• They have a role in secondary spread of lung and breast cancer
Other than the tracheobronchial lymph nodes, what other lymph nodes do the lungs drain to?
• Bronchomediastinal lymph nodes
Where are the bronchomediastinal lymph nodes found?
• hilum of the lungs
What are brinchioles responsible for?
• control of airflow
What increases in bronchioles as they branch?
• Elastic fibre content and smooth muscle content
What does the left lung posses that the right lung does not?
Cardiac impression
Aortic impression
Cardiac notch
Lingula
What does the right lung possess that the left lung does not?
- Middle lobe
- Transverse fissure
- Superior lobar bronchus
What is the hilum?
• an area on the medial surface if the lung through which structures enter or leave the lung
What ia the root?
• the structures which enter and leave the lung at the hilum
What are the 4 structures that constitutes the root of the lung?
- Pulmonary artery
- Superior pulmonary vein
- Inferior pulmonary vein
- Primary bronchi
What fascial membrane covers the apex of the lung?
Suprapleural membrane
What is a fascia?
• Band or sheet of connective tissue, primarily collagens
Do the lungs extend above the first rib?
• yes
Why is it clinically important that the lungs extend above the first rib?
• They are unprotected
Which lung is shorter and more broader?
• Right lung because it needs to make more spcae for the liver
What is the function of the fascial membrane?
• it provides rigidity to the thoracic inlet and prevents distortion due to changes in intrathoracic pressure during respiration
What features of an isolated lung should you use to ‘side’ them?
• Apex/base, orientation, lobes
Explain the entire process of the lymphatic drainage of the lungs?
1) Lungs and visceral pleura drain into bronchopulmonary lymph nodes at the bifurcation of the large bronchi at the lung hilia
2) Lymphatics pass to tracheobronchial nodes
3) Drain into the thoraic duct (left) and right lymphatic duct (right)
What is the advantage of lungs having bronchopulmonary segments?
• Each lung segment has its own blood and air supply which allows a surgeon to remove that particular segment without adversely affecting any neighbouring segments
How many bronchopulmonary segements does each lung have?
- Right - 10
* Left - 8 or 9
What is a bronchopulmonary segment of a lung?
• Segment of lung supplied by a tertiary (segmental) bronchus and an accompanying branch of the pulmonary artery and bronchial artery and vein
What are the different bronchopulmonary segments of the lung seperated by?
• Layers of connective tissue
What structures present in the bronchial wall enables its definitive identification as a bronchus?
• Hyaline cartilage
What is the pulmonary circulation?
• Portion of the circulatory system that carries deoxygenated blood away from the right ventricle of the heart to the lungs, and returns oxygenated blood to the left atrium of the heart
What are the vessels of the pulmonary circulation?
• Pulmonary veins and arteries
Where does the bronchial circulation arise?
• Aorta and 3rd posterior intercostal artery
What supplies oxygen to the lung tissue and larger airways?
• Bronchial circulation
What does the bronchial circulation supply blood to?
• Lung tissue and larger airways
How many bronchial arteries supply the right and left lungs?
- Right lung - 1
* Left lung 2
What is pleura?
• Double layer of serous membranes that surround each lung
What does pleura consist of?
- Outer parietal layer (lining the inner wall of the chest cavity)
- Inner visceral layer (adherent to the lung tissue)
- Pleural space (or cavity, which is the space between these two membranes)
Which of the parietal and visceral layer of the pleura is outer and inner?
- Parietal is outer (lines chest wall)
* Visceral is inner (lines lungs)
How would you describe the relationship between the parietal and visceral layers of the pleura?
• Continous to each other
Which layer of the pleura enters and lines the fissures of the lungs?
• Visceral
Which layer of the pleura is sensitive to pain?
• Parietal
What nerves supplies pain sensation to the pleura?
• Phenic nerve and intercostal nerves
Where does the mediastinal pleura line?
• The structures situated between the two pleural cavities (mediastinum)
Where does the diaphragmatic pleura line?
• Superior surface of the diaphragm
Where does the costal pleura line?
• Inner surfaces of the ribs and sternum
Where does the apical pleura line?
• Apex of the lungs in the root of the neck
What is the apical pleura also known as?
• Cervical pleura
What lies immediately above the apical pleura?
• A fascial membrane known as the suprapleural membrane.
What else can cause the lungs to collapse other than pneumothorax?
• inflammation/infection
What is the prescence of air within the pleural space called?
• Pneumothorax
What is the prescence of blood within the pleural space called?
• Haemothorax
What is a pleural reflection?
• A pleural reflection occurs where the parietal pleura lining one surface of the chest wall changes its direction to line another surface,
What occurs at the reflections within the pleura?
• Space between the parietal and visceral pleura is greater than normal, forming a pleural recess
What is each part of the pleura innervated by?
Parietal pleura - intercostal nerves and phrenic nerves, pain sensitive.
Visceral pleura - Autonomic nerves
What kind of innervation does the visceral pleura have?
• Autonomic innervation for stretch (pulmonary plexus)
Why do respiratory passages and the lungs appear black in CT images?
• air filled spaces
How does one view a CT scan by clinical convention?
• Feet up
What is the relative position of the oesophagus to the trachea at all points along their length?
• posterior
What rib level is the lung at in the: midclavicular line, midaxillary line, midscapular line?
- Midclavicular - rib
- Midaxillary - rib 8
- Midscapular - rib 10
What rib level is the parietal pleura at in the: midclavicular line, midaxillary line, midscapular line.
- Midclavicular line - rib 8
- Midaxillary line - rib 10
- Midscapular line - rib 12
How many intercostal spaces difference is there between the inferior border of the lung and parietal pleura at each landmark?
• 2
What organ occupies the notch seen in the anterior border of the left lung between ribs 4 and 6?
• heart
The oblique fissure follows the course of what rib?
• Rib 6
The horizontal fissure follows the course of what rib?
• Rib 4
Where does the posterior border of each lung extend from?
• C7 to T10
Why is pleural aspiration performed in the 9th intercostal space in the midaxillary line and not the 10th?
• Risk of penetrating the abdominal (pritoneal) cavity
What do extrapulmonary tubes refer to?
• Outside of the lung, such as trachea and bronchi
What is the structure from the lumen to the outside of extrapulmonary tubes?
- Mucosa
- Submucosa
- Cartilage
- Adventitia
What is the mucosa of extrapulmonary tubes composed of?
Ciliated pseudostratified columnar epithelium.
Lamina propria - underneath the epithelium contains elastin blood vessels.
What kind of tissue is the lamina propria?
• Thin loose connective tissue layer
What kind of cartilage is found in the respiratory tract?
• Hyaline
What connective tissue fibre predominates in the respiratory tract?
• Elastin
What are the 3 kinds of connective tissue fibre?
- Collagen
- Elastin
- Reticulin
What are the 3 kinds of cartilage?
- Hyaline
- Fibro
- Elastic
What type of muscle fibres is found in the respiratory tract?.
• Smooth
What are the 2 types of cells found in the respiratory epithelium layer?
• Basal and goblet cells
What type of epithelium is found in the respiratory tract?
• pseudostratified ciliated colunar epithelium
What are the small, hair like structures projecting from the epithelial cells of the respiratory tract into the lumen?
Cilia
What substances are secreted from the glands in the submucosa?
• Mucous and water
What is the function of the posterior strip of smooth muscle found in the tracheal wall?
• Aloows the oesophagus to expand, coughing
In which tissue layer of the tracheal wall are the secreting glands located?
• Submucosa
What are the type of glands found in the submucosa of the tracheal wall?
• Seromucous glands
What do the seromucous glands of the tracheal wall secrete?
• Mucous and water
How does the trachea branch?
• Trachea - primary bronchi - secondary bronchi - tertiary (segmental) bronchi - bronchioles - terminal bronchioles - respiratory bronchioles - alveoli
What bronchus is extrapulmonary?
• Primary bronchi
What bronchus is intrapulmonary?
• Secondary and tertiary bronchus
What is tertiary bronchi also known as?
• segmental bronchi
What are the 2 portions of the branches from the trachea known as?
- Conducting portion (no gas exchange)
* Respiratory portion (gas exchange)
What is the last component of the conducting system of the respiratory system?
• Terminal bronchioles
What is the beginning of the respiratory portion of the respiratory system?
• Respiratory bronchioles
What is the diameter of bronchioles?
• 1mm or less
What things are not present in bronchioles compared to trachea and larger bronchi?
• Cartilage and gland
What is still present in the terminal bronchioles that is present in larger airways?
• Some cilia and smooth muscle
What is the classification of the epithelium of terminal bronchioles?
ciliated cuboidal
What two connective tissue fibres are found in the alveolar walls?
• Elastic and reticulin
What 3 cells are found in the wall of an alveolus?
Type 1 and 2 pneumoncyte and macrophage
What is the function of a type 1 pneumocyte?
• Permit gas exchnage
What is the function of a type 2 penumocyte?
• Secrete pulmonary surfactant
What is the function of a macrophage?
• Digest foreign bodies
What is the surface markings of the pleura?
Starting 2.5cm above mid point of medial 1/3 of clavicle
Meet in midline at rib 2
Left side diverges at rib 4 to makr room for the heart, whilst the right continues parasternally to rib 6
Both cross rib 8 in the midclavicular line
Then rib 10 in the midaxillary line
Both reach posterior chest just below rib 12
(continuous red line)
What is the surface markings of the lungs?
2 rib spaces less than the pleura
blue dotted line
What are the surface markings of the fissues?
Oblique - spine of T3 vertebra to rib 6 anteriorly along medial border scapula
Horizontal (on right only) - rib/costal cartilage 4 to rib 5 in midaxillary line
What are the surface markings of the oblique fissue?
Spine of T3 vertebrae to rib 6 anteriorly along medial border of scapula
What are the surface markings of the horizontal fissure?
Rib/costal cartilage 4 to rib 5 in midaxillary line
What two process does respiration involve?
Physical and chemical
What does the physical process of respiration entail?
Ventilation involves inspiratory and expiratory movements of the chest.
What does the chemical process of respiration involve?
The exchange of gases between air and blood takes place at the cellular level
What does parasympathetic innervation do in the lungs?
Bronchioconstriction, mucous secretion and vasodilatation
What does the sympathetic innervation do in the lungs?
Bronchodilatation
What is the total distance for gas to be exchanged?
0.2 micro meters
What happens during breathlessness?
There is fluid in the gap between the alveol and the capillary and so the distance is increased and so the gas can’t diffuse properly.
What are the four main layers of the respiratory system?
Mucosa
Submucosa
Cartilage and supporting muscle
Adventitia
What consists of the mucosa?
There is a epithelium and a connective tissue layer which consists of connective tissue which is known as the lamina propria.
What does the sub mucosal layer have?
Seromucous glands
What do the seromucous glands have?
They have a duct that opens up into the lumin of the mucosa and it release mucous and serous fluids.
What is the adventitia?
It s the fibrous connective tissue which covers the tracheal bronchial treee.
What kind of cartilage makes up the rings of the trachea?
Hyaline
What are the gaps between the cartilage ring filled up with?
They are filled with trachealis muscle and fibroelastic tissue
What is the function of the respiratory mucosa and submucosal layer?
It warms and moistens the air and traps any foreign particle in the mucous
What cells are present in the mucosal layer?
Goblet cells
What cells can differentiate and act as stem cells?
Basal cells
What kind of cells are found in the trachea?
Pseudostratified ciliated columnar cells
What does the lamina propria contain?
It contains areolar connective tissue which has elastine and also blood vessels. (there might also be some macrophages and immune cells.)
Where do the pseudostratified ciliated cells start and where do they end?
It starts at the nose and finishes at the level of the terminal bronchiole
What type of cells starts from the terminal bronchiole?
Non-ciliated columnar single layer cells.
What kind of tissue makes up the lamina propria?
Loose connective tissue
What is in between the submucosal layers?
Elastic fibres
What is found in the perichondrium?
Cartilage
What is the function of the adventitia?
It connects and supports the trachea to the surrounding tissue. It also contains nerves, vessels and adipose tissue.
What two groups can we divide the bronchi into?
Intrapulmonary bronchi and extrapulmonary bronchi
What is the histology of the extrapulmonary bronchi?
They represent the histology of the trachea.
What is the histology of the intrapulmonary bronchi?
They have less cartilage and it does not completely encircle the lumen and there are layers of smooth muscle between the mucosa and sub-mucosa.
What is the diameter of a bronchiole?
less than 1mm
What are bronchioles covered in?-
Ciliated columnar epithelium (however in the smaller bronchioles it is non-ciliated)
What is different about the histology of bronchioles?
Smooth muscle increases, Clara cells are present which secrete surfactant, no goblet cells, no ciliated cells, no submucosal glands, no cartilage,
Pseudostratified columnar epithelium
What type of cells make up the respiratory bronchioles?
Ciliated cuboidal epithelium
What are alveolar ducts surrounded by?
Collagen, elastin and smooth muscle
What surrounds the alveoli and the alveolar sacs?
by blood vessels and pulmonary capillaries
What surrounds the alveoli and the alveolar sacs?
by blood vessels and pulmonary capillaries
What type of epithelium makes up the bronchioles?
Simple epithelium wth few cilia
How many glands are in the lamina propria in the bronchioles?
None
How does the smooth layer in the broncholes compare to that of the bronchi?
It is thicker.
Describe the alveolar-capillary interface.
Gaseous exchange takes place through the endothelial cell of the capillary, basement membrane and type I pneumocyte
The walls of the capillary endothelial cell is fused to that of the alveolar cell, there is only a very thin basement membrane between these two cells.
What is correct about the club cells (Clara cells)?
Protect airways, regenerate bronchiolar epithelium, produce surfactant.
Which is bigger: superior thoracic aperture or inferior thoracic aperture?
inferior thoracic aperture
What is on the interior of each rib?
It is a spongy anterior containing bone marrow which forms blood cells§
What does a tubercle correspond with?
Transverse process
How is the 1st rib different?
It is broad, it is the shortest and most sharply curved. It also articulates with rib T1.
How is the 2nd rib different?
It is thinner, it is also twice the length of the 1st rib.
What is different about ribs 10 - 12?
They only have one facet on their heads., The 11th and 12th are short and have no necks or tubercles.
Where is the subcostal space located?
Under rib 12
What makes up the subcostal nerve?
Anterior ramus of the spinal nerve T12.
At what vertebral level does the manubrium lie?
T3 - T4
What ligament joins the ribs and the vertebral bodies?
Costotransverse bodies
What kind of joint is the intervertebral joint?
Symphysis (secondary cartilaginous joint)
What kind of joint is the costovertebral joints of the head of the ribs?
Synovial plane
What kind of joint is the costotransverse joint?
Synovial plane
What kind of joint is the 1st sternocostal joint ?
Primary cartilaginous joint
What kind of joint are the rest of the sternocostal joints?
Synovial plane joints
What type of joint is the sternoclavicular joint?
Saddle
What type of joint is the costochrondral joint?
Primary cartilaginous
What kind of joint is the interchondral joint?
Synovial plane joint
What is the costochondral joint?
It is the joint between the costal cartilages and the ribs
What kind of joint is the manubriosternal joint?
Symphysis
What kind of joint is the xiphisternal joint?
Synchondroses
What level is the xiphisternal joint?
T9
Where is the weakest part of the rib?
Just anteriorly to its angle
What is flail chest?
A sizeable segment of the anterior and/or lateral thoracic wall moves freely because of of multiple rib fractures
What can a cervical rib cause and where is it normally found?
It articulates with the C7 vertebra and can compress spinal nerves C8 to T1 or the inferior trunk of brachial plexus supplying upper limb. They can also compress subclavian artery.
What can compression of spinale nerves C8 - T1 cause?
Tingling and and numbness may occur along the medial border of the forearm.
What can compression of subclavian artery cause?
Ischemic muscle pain which is caused by poor blood supply.
What is thoracotomy?
Surgical creation of an opening through the thoracic wall to enter a pleural cavity.
What is anterior thoracotomy?
It involves making H-shaped cuts through the perichondrium of one or more costal cartilages and then shelling out segments of costal cartilage to gain entrance to the thoracic cavity.
How does the breast lymph drain to the central and apical axillary nodes?
Via Infraclavicular and pectoral nodes
Where do the internal thoracic arteries arise from?
Subclavian artery
Where do the intercostal arteries supply?
The 1st six intercostal spaces
What is the arterial supply of the thoracic wall?
Posterior intercostal arteries, anterior descending arteries, branches of axillary artery.
What are the posterior intercostal arteries a branch of?
Descending thoracic aorta
What are the anterior thoracic arteries a branch of?
internal thoracic artery
What is the venous drainage of the thoracic wall?
Azygous, hemiazygous, accessory hemiazygous vein, internal thoracic vein.
where does the left side of the chest drain to?
Thoracic duct which drains to left subclavian vein.
Where does the right side of the chest wall drain to?
Right lymphatic duct which drains to the right subclavian vein.
What is the lymphatic drainage of the lungs?
pulmonary LN, Bronchopulmonary LN, Tracheobronchial LN, Bronchomedistinal LN,
What is the parasympathetic innervation of the lungs?
Vagus nerve
What is the sympathetic innervation of the lungs?
T2-5
What are the gaps between the c shaped cartilages of the trachea filled with?
Trachealis muscle and fibroelastic tissue.
