Thorax

Question 1

Mediastinum

Answer 1

▪️superior 
-divided by sternal angle
▪️inferior 
-anterior
-posterior
-middle (heart)

Question 2

Aorta in thorax

Answer 2

▪️ascending 
-anterior to trachea 
-branches to be coronary arteries 
▪️arch 
-moves backwards to left of trachea 
-branches into brachiocephalic,left common carotid, left subclavian 
▪️descending 
-posterior mediastinum 
-downwards alongside oesophagus and left lung 
-passes behind diaphragm at T12

Question 3

Aortic aneurysm

Answer 3

▪️bulging, weakened area in the wall of aorta
- become stiffer so when it contracts it starts to stretch- widening 50% the normal diameter
▪️pain in chest/back, wheezing/hard to breath due to pressure on trachea, difficultly swallowing due to pressure on oesophagus
▪️gradually increase in size
▪️treatment- surgical repair/removal aneurysm to prevent rupture

Question 4

Lymphatic drainage thorax

Answer 4

▪️anterior thoracic wall drains into
-parasternal and diaphragmatic nodes 
▪️posterior thoracic wall drains into
-intercostal  nodes 
▪️lungs drain into 
-tracheobronchial nodes 
▪️all drain into 
-brachomediastinal lymph trunk into right lymphatic duct into jugular vein

Question 5

Thoracic lymph duct

Answer 5

▪️starts at cisterna chyli- enlargement of duct

▪️passes behind arch of aorta to enter brachiocephalic vein

Question 6

Arteries supply of thoracic wall

Answer 6

▪️anterior intercostals 
-internal thoracic-subclavian 
▪️posterior intercostal 
-aorta 
▪️branches of internal thoracic artery supply diaphragm as well as phrenic arteries from aorta

Question 7

Venous drainage of thorax

Answer 7

▪️superior vena cava 
▪️inferior vena cava 
▪️brachiocephalic 
▪️internal jugular 
▪️internal thoracic  
-posterior 
▪️azygous vein - into SVC 
▪️superior and inferior hemizygous veins

Question 8

Phrenic nerve in thorax

Answer 8

▪️C3,4,5
▪️motor and sensory and sympathetic nerve fibres
▪️only motor to diaphragm
▪️supplies the mediastinal pleura and pericardium