A: brachial plexus
B: Phrenic nerve
C: Internal thoracic (mammary) artery
D: External intercostals
Posterior intercostal artery, directly from aorta, most blood in intercostal spaces comes from it.
Label A-F around the diaphragm.
B: R sympathetic trunk
C: L sympathetic trunk
E: Thoracic duct
NB: diaphragm attachement around costal margin (inferior border of lower rib)
What are the:
a) quiet inspiratory muscles?
b) accessory inspiratory muscles?
c) quiet expiraotory muscles?
d) forced expiratory muscles?
a) external intercostals, diaphragm
b) SCM, scalene
c) elastic recoil
d) internal intercostals, abdominals
What is C sensory and motor to?
What are the contents of the carotid sheath?
A: Brachial plexus
B: Vagus nerve
C: Phrenic nerve
D: L recurrant laryngeal nerve
Sensory to the two membranes it's inbetween: the mediastinal section of parietal pleura and pericardium. Motor to diaphragm.
IJV, carotid arteries, vagus (IC 10 CCs in the IV)
NB: phrenic starts more laterally and decreases to diaphragm. More anterior. Vagus starts in carotid sheath more posterior and continues to move posteriorly on L side next to oesophagus -> through osophageal hiatus (T10)
A: L recurrant laryngeal
D: azygos vein
The nerves are anterior to the lung root.
How high does the lung apex go up?
How high does the diaphragm dome go up to (e.g. in a man)?
Where is the 'safe area' of the chest for e.g. chest drain insertion - intercostal space and borders?
About 2cm above the thoracic inlet (1st rib and top of sternum)
Into 4th intercostal space (under nipple).
In 3rd - 5th intercostal space. Bordered by: lateral border of pec major and anterior border of latissimus dorsi
Describe (in terms of rib number) where the inferior lung margins are:
What rib does the horizontal fissure follow on the RHS?
What rib does the oblique fissure start?
Posteriorly, what is a marker for the oblique fissures?
a) 6th rib at mid-clavicular line
b) 8th rib
c) 10th rib
Level of shoulder blade; spine of scapula
Pic: NB light blue = costodiaphragmatic recess
What is mid-axillary thoracentesis?
Where would it be performed?
Where would a chest tube be inserted (different proceedure!)?
Investiagtion of fluid built up in chest cavity
Mid axillary line, 9th ICS, fluid built up in costodiaphragmatic recess, needle angled up to avoid liver.
What are the features on this CXR?
Pleural effusion (in e.g heart failure, lungs so saturated that fluid accumulates in pleural space. A step worse from pulm oedema.
Pulmonary oedema (fluid in intersitium)
Large cardiothoracic ratio
What can you see in this CXR?
Massive pleural effusion.
Due to heart failure prob.
What is a pneumothorax?
What are the 2 types?
Why does it kills you?
What are the characteristic radiologic features?
Abnormal collection of air in pleural spaces causing uncoupling of lung from chest wall.
Open: pressure in the pleural space equilibriates with pressure outside
Tension: air allowed into pleural cavity but not allowed to eascape -> lung may collapse
Pressure increases in affected side compessing airways, vessels and mediastinum
Asymmetrical, lack of lung markings to edge of lung field
Most are iatrogenic from e.g. artificial respiration.
What can you see in this CXR and what does this suggest?
Visceral pleural edge, air in pleural cavity
What do these CXRs show?
Pneumothorax - in 1) clearly see L lung pulled away from side, in 2) can see R visceral pleural edge
What can you see in this CXR?
Tension pneumothorax: pressure in pl cavity increases, cause cardiogenic shock b/c lung collapses onto mediastinum, and it shifts. See the trachea pushed to one side.
What is COPD?
What heart condition can COPD cause?
What are the characteristic radiological features?
Chronic bronchitis and emphysema: destruction of alveolar septae and capillaries leading to reduced elastic recoil and resultant air trapping. Air on inspiration holds small airways open, but when exhale, nothing holding then open = collpses and air remains.
R sided heart failure (cor pulmonae) b/c high BP in pulm arteries -> R side of heart works harder
Hyperinflation, flattened diaphragm, narrow mediastinum, bullae?
Pic: v. flat diaphragm in emphysema, mediastinal shillouette narrower
What is dyspnea?
What would you see on a CXR?
Difficulty breathing - e.g. those with asthma, emphysema, heart failure = use accessory muscles, may see tripod stance/barrel chest.
What does this CXR show? (Normal on L)
Hyperinflation - dyspnea
What do these lungs display?
Large bullae - increase in air spaces = emphysema
What would be the likely results/symptoms if a tumor invaded/pressed on:
b) pleural cavity
d) the SVC
e) L recurrent laryngeal nerve
f) R phrenic nerve
g) sympathetic chain in apex of thorax (stellate ganglion)
h) thoracic duct
a) lung collapse (no air in pleural cavity)
b) pain, pleural effusion
c) difficulty swallowing
d) SVC syndrome - BP of arms, head and neck higher, swelling of face and neck
f) dyspnea - paralysed R hemi diaphragm
g) Horner's syndrome: ptosis (upper eyelid droops), miosis (excessive constriction of pupil), anhydrosis, due to unopposed parasympathetic acitivity on eye
h) lymph leaks into pl carity b.c has thin wall - kylothorax = build up of lymph