Lungs and Tracheobronchial Tree Flashcards
name and describe spaces of thoracic cavity
3 spaces =
left and right pulmonary spaces
mediastinum = extrapulmonary space, between pulmonary spaces, heart and pericardium here
name contents of pulmonary spaces
pleurae
lungs
what is the first thing we see in contents of pulmonary spaces
pleurae
describe pleura
continuous serous membrane forming a sac lining both outer surface of lung and inner wall thoracic cavity and mediastinum
name pleurae and describe
visceral = outer surface of lung
parietal = inner wall of thoracic cavity (and mediastinum)
like a balloon, continuous, visceral becomes parietal, vp/pp transition, at root of lung
describe pleural cavity
Potential spaced with couple of ml of serous fluid
what is the purpose of serous fluid in pleural cavity
lubricates and helps maintain negative pressure in the cavity - inside
essential for inflation of lungs and to stay inflated
does the visceral pleura have divisions
noooo
does the parietal pleura have divisions
yeeeee
divided into regions based on what membrane faces
name parietal pleura divisions and describe briefly
- cervical (neck)- at level of superior thoracic aperture
- costal (ribs)- biggest
- diaphragm - faces and lines diaphragm
- mediastinal - diaphragm contact with mediastinum
what are pleural reflections
transitions between different regions of parietal pleura (sometimes excess folds)
what are pleural recesses
potential spaces created by excess folds of parietal pleura in areas of reflections (where they are)
room for lungs to expand during inspiration
name pleural recesses
costo diaphragmatic recess
costo mediastinal recesses
describe costo diaphragmatic recess
gutter like ring
in transverse plane
more horizontal
excess folds of costal and diaphragmatic pleurae
describe costo mediastinal recesses
left and right
in coronal plane, vertical space
bigger on left because of heart, deviated towards left
what is the critical role of pleurae in respiration
thoracic volume increases during inspiration by action of diaphragm (depresses) and accessory muscles
thoracic vol increases = lung internal pressure decreases, drops, so air rushes in
since air now with higher pressure than within lungs - rushes in to restore atmospheric pressure in lungs
only works with negative intrapleura pressure
must be maintained or else no gradient = no lung expands in response to expansion of thoracic cavity
describe pressure within pleural cavities
pressure within pleural cavities (intrapleural)= negative –> below atmospheric
lungs internal pressure (intrapulmonary) - around atmospheric
keep lungs expanded = pressure gradient
lungs (greater pressure) –> pleura (lower pressure)
what is dyspnea
Difficulty breathing
name 2 exs of dyspnea
pneumothorax
pleural effusion
describe pneumothorax
air in thorax
puncture into pleural cavity (from intercostals)
air rushes in to restore atmospheric pressure to pleural cavity
lungs - elastic tissue so collapses
can be fixed on own or surgery = fuse visceral to costal pleura to always keeps lungs inflated
describe pleural effusion
fluid build up (blood, serous fluid etc)
intrapleural pressure increases
lungs cannot expand properly = can only get smaller
difficulty breathing or shortness of breath = inability to get enough lungs into air
usually only 2-3 ml of fluid, if get infection = liquid accumulates in costo diaphragmatic recess
external features of lungs - RIGHT - LOBES
superior middle and inferior lobes
external features of lungs - RIGHT - FISSURES
Horizontal fissure = separates sup and mid lobes
Oblique fissure = separates mid and inf lobes
external features of lungs - RIGHT and LEFT - 3 SURFACES
in contact with diaphragmatic (base), costal (in contact with rib cage) and mediastinal surface (faces mediastinum)
external features of lungs - RIGHT and LEFT - HILUM
root of lung
passage of airways/vasculature
point of transition of pleurae
external features of lungs - RIGHT and LEFT - gen
apex and base
external features of lungs - LEFT - LOBES
superior and inferior lobes
external features of lungs - LEFT - FISSURES
Oblique fissure = separates sup and inf lobes
comes down obliquely from post to ant aspect
external features of lungs - LEFT - SPECIAL FEATURES
cardiac notch - heart situated here
lingula = superior lobe, tongue that wraps around ant aspect pericardium (created by heart and pericardium deviated to left)
external features of lungs - what are fissures
separations between lobes
go almost all the way back to tb tree
describe hilum and impressions - gen
Structures around = leave permanent impressions
describe right lung = hilum and impressions
svc - may or may not see
bracheiocephalic trunk
esophagus
cardiac Impression
hepatic impression = on right, liver, pushes diaphragm then that pushes lung
azygous vein = major vein, drains, thoracic cavity, arches over hilum, right side only, drains into svc, post to ant - returns to heart
describe left lung = hilum and impressions
arch of aorta - arches over hilum- arrow in diff direction = comes from heart, ant to post direction, over arch, direction of flow
cardiac impression
diaphragm leaves impression in lungs - stomach - through diaphragm onto lungs, = gastric impression
describe root of lung - gen
BAV = primary bronchus (air in and out), pulmonary artery (deoxy), pulmonary vein (oxy to heart)
right and left lungs organized differently
describe root of lung - right lung
veins on bottom
stacked vertically - 90 degrees
bronchi towards post aspect
pulmonary arteries anteriorly
more sup and post = BAV
describe root of lung - left lung
arteries= top row
bronchi = middle row
veins = bottom row
sup to inf = ABV
describe tracheobronchial tree (tb tree)
brings air in and out of lungs
sequential branching of respiratory tract
what is trachea - tb tree
supported by c shaped cartilage rings
bifurcates into right an left primary bronchi AT carina
describe rings of trachea - tb tree
rings not really complete, have connection with esophagus
also trachealis muscle
contract = narrows trachea, constrict airways
realx = trachea open
describe primary bronchi - tb tree
primary bronchi divide into secondary/lobular bronchi
right primary bronchus –> 3 secondary bronchi (sup,mid,inf)
left primary bronchus –> 2 secondary bronchi (sup,inf)
RECALL - lobes
describe secondary bronchi - tb tree
secondary bronchi divide into 2-5 tertiary bronchi (segmental)
branch out further, deeper into lungs
describe clinical consideration - tb tree
lung resections n
divisions of lungs allow for this
can take out parts of lung - if have tumour or issues, wont intefere with other parts
describe clinical consideration - tb tree
WHAT IS PNEUOMONECTOMY
entire lung
cut at primary bronchus
describe clinical consideration - tb tree
WHAT IS LOBECTOMY
lobe
cut at secondary bronchi
describe clinical consideration - tb tree
WHAT IS SEGMENTECTOMY
cut at tertiary bronchi
what is respiratory tract divided into and describe
2 main components =
conduction = from nose to terminal bronchioles
respiratory = respiratory bronchioles, alveolar sacs and ducts and alveoli
describe respiratory tract - features of pathway
tertiary/segmental bronchus (cartilage starts to disappear as goes down)
–> bronchioles (no cartilage)
= terminal bronchiole (gives rise to portion of respiratory tree where gas exchange happens) –> respiratory bbronchiole –> alveolar sacs
describe alveolar sacs - what have
alveolar sacs have alevolus - sacs for gas exchange , each alveolus has capillaries = connection between arterial side, gas exchange and pulmonary side
branch of pulmonary artery - deoxy and tributary of pulmonary vein (oxy blood)
how is pulmonary circulation organized
at level of alveolar sacs
2 pulmonary veins goes into heart
describe vasculature of lungs/pleura = pulmonary circulation
2 pulmonary arteries = deoxy blood towards lungs to be oxygenated (branch to capillaries)
4 pulmonary veins = oxygenated blood towards heart to be delivered to body (collects blood and drains)
describe vasculature of lungs/pleura = local circulation
needs own blood supply
bronchial circulation to lung tissues =
visceral pleura = bronchial arteries (oxy blood), from aorta and posterior intercostal arteries AND
bronchial veins (deoxy to alveoli for gas exchange)-to SVC
parietal pleura = intercostal a/v
describe vasculature of lungs/pleura = lymphatics
lymph collects through series of nodes from lungs to hilum (meet at) to trachea into ducts eventually draining into brachiocephalic
veins at venous angles (internal jugular & subclavian meet and form brachiocephalic vein)
* ISF in lungs brought back by lymphatic system
describe innervation of pleurae - parietal
phrenic nerve = to diaphragm too
intercostal nerves = somatosensory to costal region of parietal pleura
Parietal pleura on diaphragm = part from intercostal and part from phrenic
describe innervation of pleurae - visceral
ans and gva
describe innervation of respiratory tract (visceral)
vagus - cnX - parasym = lung tissue and tb tree
t2-t5 - sympathetic chain and ganglia (thoracolumbar flow)- symp innervation = respiratory tract
what is pulmonary plexuses
involuntary
symp and parasymp
come together and forms plexus
goes to lungs and provides ans innervation to respiratory tract
describe lung impressions - esophagus for both lungs
major component mediastinum, sometimes leaves impression
can see near arch of aorta (even tho closer to mediastinum)
