CVPR Overview of the Thorax

Question 1

Superior thoracic aperture (thoracic inlet)

Answer 1

• upper border of the manubrium, the first pair of ribs and the first thoracic vertebra

Question 2

Inferior thoracic aperture (thoracic outlet)

Answer 2

the 12th vertebra and the lower border of the rib cage to the xiphoid process of the sternum

Question 3

Diaphragm

Answer 3

dome shaped sheet of muscular and fibrous tissue that closes the inferior thoracic aperture

Question 4

Bones of the thoracic wall

Answer 4

• 12 thoracic vertebrae
• sternum
  
  • 12 pairs of ribs and their costal cartilages and intercostal spaces

Question 5

Sternal angle

Answer 5

• Junction between the manubrium and body of the sternum at T4/5 vertebral level, is a bony landmark useful for locating:
  
  • the 2nd rib
  • where the aortic arch begins and ends
  • where the trachea bifurcates
  • the boundary of the superior vs inferior mediastinum

Question 6

Intercostal muscles

Answer 6

fill the intercostal spaces and function in respiration to raise and lower the ribs

Question 7

Intercostal veins, arteries, nerves run along

Answer 7

inferior margin of the rib, in the costal groove and in the plane between the innermost and internal intercostal muscles

Question 8

Intercostal veins

Answer 8

• drain into the azygous system or the internal thoracic veins

Question 9

Intercostal arteries

Answer 9

• branch off the aorta and internal thoracic arteries

Question 10

Intercostal nerves

Answer 10

• anterior rami of the thoracic spinal nerves

Question 11

The nerves, veins, and arteries have collateral branches that run superior to the rib below the cutaneous branches at the angle of the rib between the posterior axillary and midaxillary lines and near the sternum that supply the skin

Question 12

Intercostal nerve block is injected where

Answer 12

just inferior to the rib

Question 13

Diaphragm

Answer 13

• Separates the thorax from abdomen and is the major muscle of respiration.
• Supplied by the phrenic nerves (ventral rami of C3, 4, 5)

Question 14

3 apertures of the diaphragm

Answer 14

• Caval opening (T8)- for the inferior vena cava and sometimes the right phrenic nerve; through the central tendinous part (the central tendon of the diaphragm)
• Esophageal hiatus (T10)- for the esophagus and the vagus nerves; through the muscular part
• Aortic hiatus (T12)- for the aorta, thoracic duct, azygous vein, through the right and left crura, leg shaped tendons of the diaphragm attaching to the posterior abdominal wall

Question 15

Mediastinum

Answer 15

• Everything that lies between the lungs
• Superior mediastinum and inferior mediastinum separated by a horizontal plane through the sternal angle

Question 16

Inferior Mediastinum

Answer 16

• Anterior mediastinum- primarily occupied by fat and in the adult, remnant of the thymus gland
• Middle mediastinum- contains the heart and roots of the great vessels (superior and inferior vena cavas, ascending aorta, pulmonary trunk, pulmonary veins) enclosed in the pericardial sac, and the phrenic nerves
• Posterior mediastinum- contains multiple structures including the descending aorta, azygous vein, thoracic duct, esophagus trachea and vagus nerves

Question 17

Pleural sac

Answer 17

encases the lung and formed by serous membrane called the pleura

Question 18

Visceral and Parietal Pleura

Answer 18

• Visceral pleura: part of the serous membrane that covers the lung
• Parietal Pleura: pleura that lines the thoracic wall

Question 19

Space between parietal and visceral pleura

Answer 19

pleural cavity- contains serous fluid

Question 20

Recess

Answer 20

• Result because the lungs do not completely fill pleural cavities
• Provide potential spaces where fluid can collect and fluids can be aspirated

Question 21

Costomediastinal recess

Answer 21

• anterior and largest on the left side in the region overlying the heart

Question 22

Costodiaphragmatic recesses

Answer 22

• inferior, between the lowest part of the costal pleua and the diaphragmatic pleura

Question 23

Thoracocentesis

Answer 23

• for pleural effusion
• needle is inserted along the superior margin of the rib into the pleural cavity to remove excess fluid

Question 24

What innervates costal parietal pleura

Answer 24

• intercostal nerves

Question 25

What innervates the mediastinal and diaphragmatic parietal pleura

Answer 25

phrenic nerves

Question 26

innervation of visceral pleura

Answer 26

autonomic nerves

Question 27

Pericardial sac

Answer 27

* surrounds the heart and roots of the great vessels * has two layers that make up the parietal pericardium and enclose the pericardial cavity which contains pericardial fluid * 1. inner serous layer and 2. outer fibrous layer

Question 28

Visceral pericardium or epicardium

Answer 28

* closely adhered to the heart

Question 29

Transverse pericardial sinus

Answer 29

passage between the two sited of reflected pericardium, posterior to the ascending aorta nd pulmonary trunk, and anterior to the superior vena cava and pulmonary veins

Question 30

Oblique pericardial sinus

Answer 30

* posterior to the left atrium

Question 31

Blood flow in the heart

Answer 31

* deoxygenated blood from the body enters the right atrium via the superior and inferior vena cavas * from the right atrium blood moves through the right atrioventricular valve to the right ventricle then through the semilunar valve out the pulmonary trunk to the lungs * oxygenated blood enters the left atrium from the lungs via the pulmonary veins * from left atrium blood moves throught the left AV valve to left ventricle, then through semilunar valve out the aorta to the body

Question 32

Sternocostal surface of the heart

Answer 32

primarily right ventricle