VENTILATION ANATOMY Flashcards
what lines our body cavities?
serous membranes
what are the 2 layers of secretory tissue with fluid between?
- visceral layer on the organ
- parietal layer on body wall
what are the 2 main cavities?
thoracic and abdominopelvic
what is the 2 cavities/region within thoracic cavity?
- mediastinum (heart, vessels and pericardium)
- pleura (lungs)
what is a specialised cavity within the abdominopelvic cavity?
peritoneum
what are the boundaries of the thoracic cavity?
- anterior: sternum
- posterior: thoracic vertebrae
- lateral: ribs
- superior: base of neck
- inferior: diaphragm
what are the relation of pressure and volume in ventilation
pressure inversely proportional to volume
state the Boyle’s Law
P = 1/V
explain Boyle’s Law
pressure is measured by collision:
- smaller space = more collisions –> greater pressure
- bigger space = less collisions –> decreased pressure
which state of pressure space will air move to
lower
to breathe, we need to establish a _______1______, therefore if we _____2_____ volume of the lungs, air would flow in and vice versa if we ______3______ volume of the lungs, air would flow out
1: pressure gradient
2: increase
3: decrease
are there pressure gradient between breaths? why?
no, because pressure inside cavity = pressure outside
what are the thoracic joints and what structures do they connect?
- sternocostal: 1st costal cartilage is made of cartilaginous joint to give stability, the rest is synovial joints - attach sternum to rib at sternum
- costochondral: cartilaginous joint - attach ribs to sternum at ribs
- intercondral: no bones, synovial joints connect cartilage
- costotransverse: synovial joints, articulation between ribs and transverse provess of vertebrae
- costovertebral: synovial joints, articulation between rib and body of vertebrae
what is the name of the structure that connect sternum to ribs?
costal cartilage
which of the thoracic joints are not synovial joints?
1st sternocostal and costochondral joint
what are the 2 primary muscles of respiration:
diaphragm and intercostals (there are also some accessory muscles but we don’t need to learn further of this)
what does muscle of respiration do?
move the rib cage to allow us to breathe
what is diaphragm made of?
skeletal muscle for voluntary control
what is the shape of diaphragm during relax and contract?
- relax: dome-shaped
- contract: flattens
what does contraction of diaphragm cause?
expansion of thoracic cavity and compression of abdominopelvic cavity
TRUE/FALSE: diaphragm has holes for inferior vena cava, esophagus and aorta to go thourhg
TRUE
where is intercostal attach?
diagonally between neighbouring ribs
what does external intercostals do?
- lift rib cage and expand cavity
- inspiration - quiet and force
what does internal intercostals do?
- depress rib cage and decrease cavity
- expiration - forced only
what happens during normal quite inspiration and expiration?
- inspiration: diaphragm contracts (flattens) and external intercostals contract
- expiration: diaphragm relaxes and external intercostals relax - passive process
what happens during active forced inspiration and expiration?
- inspiration: diaphragm contracts, external intercostals contracts and accessory muscles contract to further expand thoracic cavity
- expiration: diaphragm relaxes, external intercostals relax, internal intercostals contract and accessory muscles contract to further decrease thoracic cavity volume
how does lungs expand as the cavity does?
- lung tissue is elastic and always trying to recoil
- pleura makes the lungs ‘stick’ to thoracic wall
____1_____ pleura is on lungs and ____2_____ pleura is on thoracic wall.
there is ______3_______ in between the pleuras to assist frictionless movement against other structure as the bond cause lungs ______4______ to the wall
1: visceral
2: parietal
3: pleural fluid
4: stick
what are the key anatomical features of the thoracic cavity?
bones joint and muscles form thoracic wall, mediastinum inside cavity plus lungs within double layer of pleura
