Lecture 18: Pulmonary A&P Flashcards
what forms the thoracic cavity and what is contained within
formed by ribs, thoracic vertebrae, sternum, and clavicles
contains R and L pulmonary cavities and mediastinum
provides skeletal framework for attachment of mm used for breathing
describe the sternum and its components
flat breastbone; sits directly over mediastinum
manubrium = thickest part; articulates with clavicles and ribs 1-2
body = articulates with ribs 3-7
diploid = most caudal potion of sternum; doesn’t ossify until teens
angle of Louis = marks level of tracheal bifurcation into R and L main stem bronchi
what are vertebrosternal ribs
“true ribs”
ribs 1-7 attach to the sternum via the costal cartilage
what are vertebrochondral ribs
“false ribs”
ribs 8-10 attach to rib above via their costal cartilage
ribs 11-12 end freely
what is the weakest point of the rib
the shaft where vertebral and sternal end connects
purpose of inspiratory mm
increase volume of the thoracic cavity by producing “bucket handle” and “pump handle” movements of the ribs and sternum
diaphragm is the primary inspiration mm (phrenic nn C3-5)
external intercostals also assist with inspiration
how does the diaphragm move with breathing
moves downward with contraction to increase thoracic volume
vacuum effect pulls air into lungs
what do the intercostals do with inspiration
elevate ribs and expand chest
name the accessory inspiratory muscles
SCM
scalenes
upper trap
pec major and minor
serrates anterior
rhomboids
latissimus dorsi
serrates posterior superior
thoracic erector spinae
what muscles are involved with expiration
expiration = more passive than inspiration via elastic recoil; less energy required
abdominal mm = increase intra abdominal pressure for expulsion of air
internal intercostals = depress ribs and decrease thoracic volume
describe different anatomical components of the lungs
consists of airways and blood vessels to perform gas exchange
apex = superior cone shaped potion underneath and superior to rib 1
base = inferior/diaphragmatic surface
root = endurance of bronchi, pulmonary arteries/veins, lymphatics, nn into each lung
hilum = mediastinal surface where structures of the root enter the lung
describe the R lung
larger
3 lobes (superior, middle, inferior)
2 fissures ( horizontal and oblique)
describe the L lung
smaller
2 lobes (superior and inferior)
1 fissure (oblique)
cardiac notch
what is the purpose of dividing lungs into segments
R and L lungs are broken down into segments that correspond with their air supply
used for naming location of infection, surgery, tumor, fluid accumulation, etc
describe the parietal pleura
on chest wall
highly innervated
capillaries receive blood from systemic circulation
higher capillary blood pressure
describe the visceral pleura
directly on lungs
no sensory innervation
capillaries receive blood from pulmonary circulation
lower capillary blood pressure
describe the difference in blood vessels that vascularize the parietal pleura vs the visceral pleura
parietal = vascularized by high pressure systemic blood vessels
visceral = vascularized by low pressure pulmonary blood vessels
how does the pressure gradient work to move fluid in and out of the pleural region
normal pressure gradient causes constant fluid movement out of the parietal capillaries into the pleural space and is then reabsorbed by visceral capillaries
how much fluid passes through the pleural space
5-10L fluid per day
what are the components of the upper respiratory tract and their function
nose = air filtration, humidification, temp control, and olfaction
pharynx = throat; connects nasal cavity to tracheoesophageal junction
larynx = voice box; sits directly on top of the trachea