Thorax - heart and lungs Flashcards
true ribs
costal cartilages of the upper 7 rib pairs articulate with the sternum
false ribs
ribs 8, 9 and 10, attach to cartilage of 7th rib
floating ribs
11 and 12, do not connect with anything
flail chest
multiple rib fractures can create this, can impede respiration
typical rib
Head, Neck, Tubercle, Body
Articulates with transverse process and vertebral body of vertebrae – costovertebral joints
sternum
o Manubrium – top part of sternum, where 1st rib and clavicle articulate
Sternal angle – between manubrium and body, where 2nd rib articulates
o Body – main part
o Xiphoid process – bottom, approximately around T9
thoracic apertures
o Superior thoracic aperture – 1st rib to manubrium
o Inferior thoracic aperture – costal cartilage of 7-10 ribs, diaphragm lines this
external intercostal muscles
forms V shape, “hands in pockets”, superolateral to inferomedial
internal intercostal muscles
forms mountain, expiration and proprioception
innermost intercostals
vessels run between innermost and internal
intercostal muscles are innervated by
intercostal nerves
chest tube
should be inserted superior to rib because inferior to rib the intercostal bundle (n. a. v.) are inferior to the rib
diaphragm
moves up and down when you breathe o Caval opening – inferior vena cava at T8 o Esophageal hiatus – esophagus at T10 o Aortic hiatus – aorta at T12 o Inspiration – contracts and flattens o Expiration – relaxes and rises
intercostal nerves
(ventral rami of spinal nerves TI to T11)
o Lateral and anterior cutaneous branches
intercostal vessels
branches of aorta
o Lateral cutaneous branches
pleural cavity
true cavity in thorax
visceral pleura
autonomic innervation sensitive to stretch
parietal pleura
have somatic innervation and very sensitive to pain o Four parts Diaphragmatic – superior Mediastinal – lines lung and heart Costal – lines internal ribs Cervical (cupola)
costodiaphragmatic recess
right lung, inferior
costomediastinal recess
left lung, anterior near midline around where heart is
4 lung surfaces
o Costal – against ribs
o Diaphragmatic – base, against diaphragm
o Mediastinal – contains hilum
o Hilar – where main bronchus, pulmonary arteries and veins are
fissures of right lung
oblique and horizontal because 3 lobes
fissures of left lung
only oblique
carina of trachea
ridge of cartilage where trachea splits into 2 bronchi, at sternal angle
main primary bronchi
Right main bronchus – bigger than left, higher chance of catching debris
Left main bronchus
lobar secondary bronchi
Right – superior, middle and inferior (3)
Left – superior and inferior (2)
Do not memorize bronchopulmonary segments
pulmonary arteries
carry deoxygenated blood from heart to lungs
pulmonary veins
carry oxygenated blood from lungs to heart
bronchial arteries
supply bronchi with blood from thoracic aorta
superior mediastinum
trachea and esophagus
o Sternal angle and intervertebral disc between T4 and T5, separates superior from inferior
inferior mediastinum
o Middle mediastinum – heart
o Anterior mediastinum – fat, lymph tissue, thymus
o Posterior mediastinum – inferior-most, aorta, esophagus
pericardial sac
holds heart, has fibrous and serous layers
fibrous pericardium
strong dense collagen material that blends with tunica externa
serous pericardium
lines inner surface of fibrous pericardium
parietal layer of pericardium
of serous, outer, has space between it and visceral layer
visceral layer of pericardium, epicardium
follows heart contours, at root it is continuous with pericardium, single layer of epithelium
• The aorta attaches the heart to the body; essentially only anchor
• Pericardial effusion – when it ruptures and heart bleeds into the pericardial cavity, the heart can’t fill and is dangerous
endocardium
layer of heart muscle most susceptible to ischemia
transverse pericardial sinus
space about heart and around aorta