anatomy of thorax and lungs

Question 1

what are the main anatomical features of the thorax?

Answer 1

thoracic outlet, thoracic inlet, heart, lungs, sternum and ribs

Question 2

where does the thoracic inlet attach?

Answer 2

T1 posteriorly
1st rib bilaterally
costal cartilage of 1st rib and superior border of manubrium

Question 3

where does the thoracic outlet attach?

Answer 3

T12 posteriorly
11th and 12th ribs laterally
costal cartilage of 7th-10th ribs and xiphisternal joint anterolaterally

Question 4

what is the manubrium?

Answer 4

part of the sternum

Question 5

what are the three classes of ribs?

Answer 5

true- 1st-7th because they’re directly connected to the sternum
false- 8th-10th because they’re indirectly connected to the sternum
floating- 11th-12th because they’re not connected to the sternum

Question 6

describe superficial intercostal muscles

Answer 6

formed by external intercostal muscles and the fibres have an inferior direction

Question 7

describe middle intercostal muscles

Answer 7

formed by internal intercostal muscles and fibre direction is inferiorposteriorly

Question 8

in what order does the neuromuscular bundle above the intercostal muscles go?

Answer 8

vein-artery-nerve

Question 9

where does VAN lie between?

Answer 9

internal ad innermost intercostal muscles

Question 10

what do external intercostal muscles become (anteriorly)?

Answer 10

external intercostal membrane

Question 11

what do internal intercostal muscles become (posteriorly)?

Answer 11

internal intercostal membrane

Question 12

where do the innermost intercostal muscles exist in relation to the thoracic cage?

Answer 12

only in the middle part of the thoracic cage

Question 13

how is blood supplied in the thoracic cage ?

Answer 13

by the posterior intercostal arteries, anterior intercostal arteries and branches of axillary arteries

Question 14

where does venous drainage from the thoracic cavity drain to?

Answer 14

into the azygous system

Question 15

where does the mediastinum extend to and from?

Answer 15

from the thoracic inlet to the diaphragm

Question 16

where does the mediastinum divide into superior and inferior?

Answer 16

at the sternal angle

Question 17

what does the inferior part of the mediastinum divide into?

Answer 17

middle- contains heart, vessels, oesophagus, thymus and lymph nodes
anterior and posterior- contains lungs and pleura

Question 18

what is the posterior and middle parts or the inferior mediastinum deviated by?

Answer 18

pericardial sac

Question 19

describe lymphatic drainage on the anterior chest wall and breast

Answer 19

left side of chest- thoracic duct into left subclavian vein
right side of chest- right lymphatic duct into right subclavian vein
breast- axillary lymph node, parasternal lymph node, abdominal lymph node

Question 20

where do phrenic nerves pass through?

Answer 20

root of phylum, side of heart and innervates the diagram

Question 21

where do phrenic nerves originate from?

Answer 21

C3-C5 and they are both sensory and motor

Question 22

from what position do phrenic nerves pierce and innervate the diaphragm?

Answer 22

inferiorly

Question 23

what supplies the central part of the diaphragm?

Answer 23

phrenic nerves

Question 24

what happens if phrenic nerves are damaged?

Answer 24

the side on which the nerve is damaged will be paralysed
eg. if the right phrenic nerve is damage the right side of the diaphragm dome will be paralysed so it wouldn’t descend during inspiration

Question 25

where does the costovertebral joint lie?

Answer 25

between ribs and vertebrae

Question 26

in the 1st rib where do the anterior and posterior grooves lodge?

Answer 26

anterior- subclavian vein | posterior- subclavian artery and lowest trunk of the brachial plexus

Question 27

in regards to the ribs what increases during forceful inspiration?

Answer 27

transverse diameter of rib and intercostal diameter of thoracic gate, this elevates sternum and ribs upwards

Question 28

describe the right and left crus of the diaphragm

Answer 28

right crus- L1-3 vertebrae, prevents the reflux of gastric content back to the oesophagus left crus- L1-2

Question 29

what are the 3 openings (hiatuses) of the diaphragm?

Answer 29

T8- caval opening T10- oesophageal opening T12- aortic hiatus

Question 30

what are the two parts of the respiratory tract and what do they contain?

Answer 30

upper respiratory tract- nose, pharynx, larynx | lower respiratory tract- trachea, bronchi, bronchioles

Question 31

how many bronhiopulmonary segments does each lung have?

Answer 31

10

Question 32

what surrounds the right lung mediastinal surface?

Answer 32

heart, superior/inferior vena cava, oesophagus, right subclavian vein and artery

Question 33

what surrounds the left lung mediastinal surface?

Answer 33

heart, aortic arch, thoracic aorta, oesophagus, left subclavian vein and artery

Question 34

where does the trachea start and where does it bifurcate?

Answer 34

starts at C6 (lower larynx) and splits at sternal angle to give rise to the right and left bronchus

Question 35

what is the tracheobranchial tree?

Answer 35

branching structure of airways which consists of conducting and respiratory portions conducting portion does not undergo gas exchange respiratory portion undergoes gas exchange

Question 36

what does the conducting portion of the tracheobronchial tree consist of?

Answer 36

``` trachea main bronchus lobar bronchus segmental bronchus conducting bronchiole terminal bronchiole ```

Question 37

what does the respiratory portion of the tracheobronchial tree consist of?

Answer 37

respiratory bronchiole alveolar duct alveolar sac alveolus

Question 38

what are the 3 lobes, borders and surfaces of the lungs?

Answer 38

lobes- superior, inferior, middle(only in right lung) borders- anterior, posterior, inferior surfaces- costal, mediastinal(medial), diaphragmatic(inferior)

Question 39

how many fissures are in the left and right lungs ?

Answer 39

right- 2 horizontal and oblique | left- 1 oblique

Question 40

what is the lingula?

Answer 40

tongue like projection of the left lung under the cardiac notch

Question 41

what is a lung root?

Answer 41

structures such as bronchus, artery, veins, lymphatics and nerves that enter or leave the hilum

Question 42

what is the hilum?

Answer 42

area located on mediastinal surface

Question 43

how can you identify the left hilum from the right hilum ?

Answer 43

right- bronchus dividing into 2 pulmonary arteries which enter inferiorly and 2 pulmonary veins left- 2 pulmonary veins

Question 44

why are the pulmonary veins in the hilum red?

Answer 44

because they carry oxygenated blood

Question 45

what is the clinical advantage of bronhopulmonary segments?

Answer 45

in cases of cancer the cancer cause be surgically removed from one segment before it moves into another

Question 46

what is the lung supplied and drained by?

Answer 46

supplied by bronchial arteries (thoracic aorta, posterior intercostal artery) drained by bronchial veins (azygous)

Question 47

how does pulmonary innervation around the hilum happen?

Answer 47

by the pulmonary plexus

Question 48

what does the pulmonary plexus contain?

Answer 48

parasympathetic fibres- vagus nerve either motor to bronchial muscle (causes bronhoconstriction) or secretomotor ( secretes mucus and vasodilator) to mucus glands sympathetic- T2-5 either inhibitory to bronchial muscle (bronchodilator) or motor to blood vessel muscle

Question 49

how many intercostal spaces are between the lung and the pleura?

Answer 49

2 lung- midclavicular 6, midaxillary 8, paravertebral 10 pleura- midclavicular 8, midaxillary 10, paravertebral 12

Question 50

what's the pleura that's attached to the lungs?

Answer 50

visceral

Question 51

what's the pleura that's attached to the thoracic cage?

Answer 51

parietal

Question 52

what nerve supply is associated with the visceral and parietal pleura?

Answer 52

visceral- autonomic | parietal- somatic

Question 53

what's the pleural sac?

Answer 53

serous fluid, flows movement of lung during inspiration and expiration

Question 54

what's plural recess and reflection ?

Answer 54

recess- loose pocket at the lower part of the pleural sac where fluid accumulates reflection- place at which parietal pleura changes direction to become visceral pleura