Anatomy of the thorax Flashcards
What innervates sternocleidomastoid
XI
What innervate Pec Major
- Pectoral nerves C5-T1
What innervates Pec Minor
- Pectoral nerves C5-T1
What innervates serratus anterior
- Long thoracic nerve C5-C7
What innervates the external intercostal muscles
- Intercostal nerves T2-T11
What innervate the rectus abdominis
- Intercostal and subcostal nerves T7-T12
describe where serratus anterior runs
- This muscle runs deep to the scapula, it comes from the medial aspect of the scapula and runs towards the ribs
describe where the long thoracic nerve runs
- The long thoaricic nerve runs sueprifically along the muscle and then pierces it
- It makes up the medial border of the axilla
what are the roots of the long thoracic nerve
C5 C6 C7 wings to heaven
what do the external intercostal muscles do
- These elevate the ribs bringing them up and out
- They are involved in inspiration
- Come from superior rib and wrap anterior superior direction
where does the rectus abdomens attach
- This attacks to the costal margin and xiphoid process and runs along the abdomen to insert on the pubic symphysis
what is the role of the rectus abdomens
- Pulls down the ribcage
- Involved in forced expiration
what do the internal and innermost intercostal muscles do
- Go from an superior inferior position
- Pulls the ribcage down and in
- Involved in forced expiration
which order is the artery nerve and vein in in the chest wall
- Goes VAN (vein artery nerve)
what are the two intercostal arteries
- anterior and posterior intercostal artery
describe where the posterior intercostal artery originates from and where it drains
- bigger than anterior
- they are from the aorta branches
- they drain into the azygous vein which arches up over the lung root to drain into the SVC
describe where the anterior intercostal artery originates from and where it drains
- Anterior intercostal are from the internal thoracic artery,
- they drain into the internal thoracic vein
what is thoracocentisis for
- To sample pleural fluid
* Small needled into the pleural cavity to remove a small amount of fluid
How do you thoracocentesis
- To avoid damage to the intercostal nerves the needle is inserted superior to the rib.
- When the patient is in the upright position fluid will accumulate in the costophrenic recess.
- The 9th mid-axillary line during expiration avoids the inferior border of the lung
How do you do a chest drain
- The 5th intercostal space in the mid-axillary line is usually used
- Safe triangle
- Lateral border of pec major, apex below the axilla, anterior border to lat dorsi, a line superior to the horizontal level of the nipple
what is the diaphragm innervated by
- Innervated by the phrenic nerve C3, C4, C5 keeps the diaphragm alive
what pierces the diaphragm and at what level
- Vena cava T8
- Oesophagus T10
- Aorta hitatus T12
What are the two types of pleura
- Parietal pleura – thoracic wall and superior surface of diaphragm
- Visceral Pleura – covers external lung surface
what is between the parietal and visceral pleura
• Pleura (parietal) produce pleural fluid – fills cavity, this reduces friction when the lungs expand during breathing as well as help stick the lung to the parietal layer
what is the pleura not supposed to be visible on
• It should not be visible on a chest X ray
if you have a pneumothorax what can you see
• If you have a pneumothorax then you can see the pleura
what is the nerve supply of the visceral pleura
has the same nerve supply as the lung, has para and sympathetic nerve supply, therefore it cannot perceive pain
what is the nerve supply of the parietal pleura
has the same nerve supply as the chest cavity, T2-T12 intercostal nerves
How is the costophrenic recess formed
- Parietal plerua continues 2 ribs inferior to the inferior border of the lung lobe
- It follows the dipahgran and you end up with a space below the lung which is the costeoprhenic recess, this helps form the costophrenic angle
what does a blurred costophrenic angle mean
- it means that there is fluid there
describe the structure of the lungs and where they can be found
- Apex of lung 2cm above the clavicle
- Cardiac notch at 4th rib
- The lungs can be found at 6, 8, 10
- Pleura boundaries are at (midclavicular line)8,(axillary) 10, (posteriorly) 12
what is the difference between the lobe on the right and the lobe on the left
On left hand side
- Superior and inferior lobe
- Divided by the oblique fissure
Right hand side
- Superior, middle, inferior
- Superior and middle are Divided by horizontal
- and middle and inferior are divided by oblique fissure
describe what the entrance into the right and left lung looks like
Pulmonary vein is inferior to the pulmonary artery
Bronchus has cartilage in it
describe the divisions of the lungs
- trachea - bifurcates at the level of the sternal angle into the main bronchus
- main bronchus
- lobar bronchus
- segmental bronchi
- conducting bronchioles
- terminal bronchioles
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
what is the difference between the right and left main bronchus
Right main bronchus is more vertically orientated and larger than left main bronchus
Left main bronchus is more horizontal
How many ribs do you expect to see in a normal chest x ray
- Expect to see between 5 and 7 ribs above the diaphragm
if you can see more ribs that normal in a chest x ray what does this mean
- If you can see more ribs than that then there is hyper expansion of the lungs, the lungs have too much air in
describe emphysema
- Destruction of alveolar walls leading to permanent enlargement of air spaces
- Surface area dramatically reduced
- Loss of elastic tissue so less recoil of the lungs
- Narrowed bronchioles
- This leads to air trapping within the lungs
- Air not fully expired and the lungs become hyperexpansed
where is the superior mediastinum
Superior Mediastinum is found above the angle of louis
what does the superior mediastinum contain
- Great vessel
- Oesophagus
- Trachea
- Thymus
- Phrenic nerves
- Vagus nerves
- Recurrent laryngeal nerves
- Thoracic duct
what is the inferior mediastinum divided into
the anterior, middle and posterior
what is in the posterior mediastinum
- Azygous azygoose
- Vagus vagoose
- Oesophagus oesophagoose
- Throacici duct thoracic duck
- Thoracic aorta
where is the posterior mediastinum
- Anterior to vertebrae T5-T12, inferior to sternal angle and posterior to pericardium
what is the spinal segements of the sympathetic chain
- T1-L2 sympathetic chain ganglion
what does the sympathetic chain do
- Fight or flight response
- Pupil dilation
- Bronchodilation
- Cardiac acceleration
- Inhibition of digestion
- Filling of the bladder
- Pheripheral vasoconstriction
- Piloerection – erect of pili Hair
what is the stellate ganglion
The stellate ganglion is a collection of nerves (sympathetic) found at the level of the sixth and seventh cervical vertebrae (the last vertebra of the neck)
- they supply the face and arm
what is the recurrent laryngeal nerve
A branch of the Vagus nerve which branches within the thorax and loops around the arch of the aorta on the left and the Subclavian artery on the right.
what does the recurrent laryngeal nerve supply
. It then runs back up to the larynx where it supplies the vocal cords (the intrsic muscle) which are responsible for moving the vocal cords and producing phonation).
