Pleura and lungs Flashcards
The thoracic inlet is bound by what?
manubrium, rib 1 with associated costal cartilage, and T1 posteriorly
The thoracic outlet is inferior and surrounded by what?
T12, the costal margin (bottom edge of the rib cage), and the xiphisternal joint
(between the xiphoid process and body of the sternum)
The thoracic outlet is closed by what?
diaphragm
What is the thoracic wall?
sternum, 12 pairs of ribs and vertebral column
The thoracic cavity is bound by what?
thoracic wall, diaphragm and superiorly the suprapleural membrane
What is the suprapleural membrane?
a layer of fascia arching over each lung and extending up into the thoracic inlet
Pleural cavities surround ___ ___
each lung
Pleural cavities are lined by what?
serous membrane (pleura) but the cavity itself remains empty
What separates the lungs?
mediastinum
How does the lung bud grow?
grows into a serous sac and becomes completely enveloped except at the point where the lung is anchored to the mediastinum
What is visceral pleura?
pleura on the surface of the lung
What is the parietal pleura?
pleura on the body wall
Is visceral pleura sensitive to pain?
No
Is parietal pleura sensitive to pain?
highly sensitive due to innervation by the intercostal nerves and the phrenic n.
The parietal pleura lines the ____ ____ and is separated from the musculature by ___ ___
thoracic wall; endothoracic fascia
What are the parietal pleura divisions and what are they based on?
Based on the portion of the thoracic cavity it is found in
- costal pleura
- mediastinal pleura
- diaphragmatic pleura
- cervical pleura
Where is the costal pleura found
lines the back side of the thoracic rib cage
Where is the mediastinal pleura found
lines the mediastinal mass
Where is the diaphragmatic pleura found
lines the diaphragm
Where is the cervical pleura found
covers the apex of the lungs
Costal pleura innervation
intercostal nerves of the intercostal space
Diaphragmatic pleura innervation
intercostal nerves peripherally and the sensory component of the phrenic nerve centrally
What nerve innervates the visceral pleura?
None, visceral pleura is not innervated
What is the pulmonary ligament?
parietal pleura reflects off the mediastinum onto the surface of the lung, as visceral pleura, at the root of the lung; the parietal pleura sags below the root (like the cuff on a shirt) forming an unfilled potential space- this double layer of pleura forms this ligament
The viscera pleura dives where?
it attaches intimately to the surface of the lung and cannot be lifted, it dives deep into the fissures of the lung before reflecting up on the adjacent lobe
What are pleural recesses?
areas where the parietal pleura reflects off one aspect of the thoracic cavity onto another, forming potential spaces; recesses are never completely filled by the lung
How is the costomediastinal recess formed?
formed by the reflection of the mediastinal pleural off the mediastinum onto the costal wall - forming a vertical strap-like recess on either side of the sternum
How is the costodiaphragmatic recess formed?
formed by the reflection of the diaphragmatic pleura off the diaphragm onto the costal wall. - forming a semicircular recess that communicates with the costomediastinal recess anteriorly and passing posteriorly to meet the
vertebral column
The entire thorax is lined by what?
endothoracic fascia
Function of the endothoracic fascia
adheres the parietal pleura to the various aspects body wall, mediastinum and diaphragm
The thoracic inlet is also called what?
operculum
Cervical pleura is also called what
cupola
What are suprapleural membranes
the endothoracic fascia extending across the thoracic inlet above the cervical pleura forms these membranes
When you inspire, your diaphragm moves in what direction?
more inferiorly
When you expire, your diaphragm moves in what direction?
more superiorly
How do visceral and parietal layers stayed attached to one another?
through capillary action; negative pressure keeps the lung stuck but slippery to the back of the thoracic wall
What happens when the thoracic muscles cause the rib cage to elevate?
thoracic diameter is expanded when you inhale and it sucks the lung with it; thoracic diameter is reduced when you exhale which squeezes air out of the lungs
What is a pneumothorax?
allowing air into the pleural cavity, separating the two layers of pleura and resulting in a collapsed lung
-can caused by a knife wound
How does a pneumothorax occur?
visceral or parietal pleura is punctured (either by a stab wound or spontaneous rupture by emphysema in the visceral pleura), the elastic recoil of the tracheobronchial trees sucks air into the pleural cavity (sac), he two pleural surfaces separate and the lung “collapses”
-The tear/puncture must be closed to re-establish
negative pressure
How many lobes of the right lung?
3
How many lobes of the left lung?
2
What are the lobes of the right lung
superior, middle, inferior
What are the lobes of the left lung
superior and inferior lobes
Horizontal fissure of the right lung is located where?
Between the superior and middle lobes
Oblique fissure of the right lung is located where
Between the middle and inferior lobes
Oblique fissure of the left lung is located where
Between the superior and inferior lobes
What is the apex of lungs?
located at the top of the superior lobes
Where is the cardiac notch located?
in the superior lobe of the left lung, place where it associates with the heart
Where is the lingula located?
bottom portion of the superior lobe of the left lung, below the cardiac notch
During inspiration, what direction do the lungs move?
they move in medially towards one another and also inferiorly because they expand during inspiration
What is the hilum of the lung?
the root of the lung; what connects your lungs to their supporting structures and where pulmonary vessels enter and exit your lungs
The right lung has what impressions on its medial surface?
- impression of right subclavian a.
- esophageal impression
The left lung has what impressions on its medial surface?
- aortic impression
- cardiac impression
The pleural recesses accept what?
the sharp inferior and anterior borders of the lungs during inspiration; Fluid may also accumulate in these spaces and knowledge of their extent is important for its aspiration
What structures are found in the hilum?
Pulmonary vv., pulmonary aa., bronchi, and broncho-
pulmonary lymph nodes
Bronchial aa. supply what
oxygen-laden blood to the lung tissue, as branches directly off the aorta
Bronchial vv. drain what?
carbon dioxide-laden blood from the lung tissue into the azygous system
Pulmonary aa. are located where?
above the bronchi except for the secondary bronchus to the right upper lobe
Pulmonary aa. follow what?
follow the bronchi all the way to the level of their termination as alveoli
The alveoli are drained by what?
intersegmental pulmonary vv. which diverge from the bronchi
Pathway of the pulmonary vv.
extend through the intersegmental connective tissue septa. They eventually coalesce and rejoin the tracheo-bronchial tree at the level of the tertiary
bronchi.
The pulmonary vv. are often used as guidelines for what?
surgical resection of the broncho-pulmonary segment
What vertebral level does the trachea bifurcate?
at the sternal angle, T4/T5- bifurcates into two main bronchi
The right primary bronchus is ____, which is the primary reason that most inhaled objects end up in this bronchus
short
The left main bronchus is ____ than the right and more ____, leaving the trachea at a distinct angle
longer; horizontal
What is a BPS?
Bronchopulmonary segment
a BPS is what
smallest resectable portion of the lung and is supplied by a tertiary bronchus
Each lung has how many BPS’s?
10
Why is the location of the BPS’s important?
important with reference to positioning the body for draining regions of the lung by percussion (postural drainage)
Lung cancer incidence places importance on ____ ____
lymphatic drainage
A superficial lymphatic plexus lies where?
just under the visceral pleura
A deep lymphatic plexus lies where?
It follows the bronchial tree
Where do the two lymphatic plexuses meet?
meet at the hilum of the lung where they drain into the bronchopulmonary group of nodes at the root of the lung
Where does the lymph go after going through the root of the lung?
passes through the tracheobronchial and paratracheal nodes and eventually into the venous system via the thoracic or right lymphatic ducts that enter the
subclavian vv
What is the carina?
cartilaginous septum at the bifurcation of the trachea
