Anatomy of Pleural cavities and lungs week 5 Flashcards
COPD
refers to a group of lung diseases in which airflow is blocked, thus making breathing difficult. The two most common diseases in this group are emphysema and chronic bronchitis. Emphysema occurs when the alveolar sacs are gradually destroyed while chronic bronchitis is a condition where there is inflammation in the bronchi.
asthma
Asthma is a chronic lung disease which involves inflammation, edema, spasm, and narrowing in the bronchial tree. Part of the disease process is an increased sensitivity to inhaled substances as a result of the changes in the airway. In the US over 25 million people are known to have asthma and about 7 million of these are children.
What are the boundaries of the pleural cavities?
What can occur to the lung if there is fluid accumulation in the pleural space? What symptom would the pt complain of? (other than pain)
Normally, there is a small amount of serous fluid in the pleural cavity that allows the parietal and visceral pleura to slide past one another during breathing.
If there is fluid in the pleural space, it can cause a collapsed lung. Pt will c/o SOB bc lung has hard time expanding.
What are the 4 parts of the parietal pleura?
If there is inflammation of the parietal pleura, pt will c/o pain. What nerves allow for this pain to be sensed? What parts of the parietal pleura are innervated by which nerves? What type of nerve fibers are contained in these nerves?
How does the parietal pleura receive its blood supply?
- The phrenic nerve provides sensory innervation to the mediastinal and diaphragmatic parts of the parietal pleura. Intercostal nerves provide sensory innervation to the costal portion of the parietal pleura. Both of these nerves provide GSA innervation.
- from branches of the thoracic wall
How is the visceral pleura innervated? How does it receive blood supply?
- GVE and GVA fibers of the pulmonary plexus. Note that the visceral pleura does NOT receive somatic innervation while the parietal pleura does.
- broncial arteriesddf
What is the root of the lung?
What is the hilum of the lung?
The “root of the lung” refers to the tubular sleeve of mediastinal pleura that surrounds structures passing between the lungs and the mediastinum (bronchi, pulmonary vessels). The root joins the medial surface of the lung at a region called the hilum. Here, parietal and visceral pleura are continuous.
During normal quiet breathing, the lungs do not completely fill the anterior or posterior-inferior regions of the pleural cavities. Expansion of the lungs into these recesses occurs during what type of breathing?
What are these recesses called? What are they formed by? If there is fluid in these recesses, where will it be seen on a chest X-ray?
What recess is found only on the left side? Why is it only on the left?
- expansion of lungs into these recesses occurs only during forced inspiration.
- costodiaphragmatic recesses are formed by the parietal pleura only (obviously bc the visceral pleura is adherent to the lungs). fluid may be seen accumulating in this space and the costophrenic angles will not be as sharp.
- costomediastinal recess is only on the left side. occurs bc the heart encroaches on the space that the left lung would take up if the heart were not there
In relation to the root of the lung, where do the phrenic nerves course? What structures do the phrenic nerves innervate other than the parietal pleura?
The phrenic nerves are adherent to the pericardium (the sac around the heart). These nerves pass just anterior to the root of the lung on their course to innervate the diaphragm.
The phrenic nerve innervates the fibrous pericardium and the diaphragm (C 3,4,5 keeps the diaphragm alive)
Where do the pulmonary arteries of the left and right lung course in relation to the left and right mainstem bronchi?
Btwn the right pulmonary artery and right mainstem bronchus, which is most superior?
Where are the pulmonary veins in relation to the mainstem bronchi and the pulmonary arteries?
RALS
right pulmonary artery is anterior to the right mainstem bronchus. note that right mainstem brochus is superior to the right pulmonary artery (posterior and superior)
left pulmonary artery is superior to the left mainstem bronchus. left mainstem bronchus is also posterior
pulmonary veins are the most inferior structures of the hilum of the left and right lungs
also see slide 14 of notes
What is the pulmonary ligament?
It is a redundancy of the root of the lungs to allow for room of expansion of the pulmonary vessels.
If a person aspirates, where does it tend to go?
Into the right lung bc the right mainstem bronchus is wider and straigher. The left mainstem bronchus is oblique and is not as wide.
Identify the levels of the bronchial tree and the lobes of the left and right lungs.
Note that the upper lobar (secondary) bronchus in the left lung has a pseudobronchus that appears as if it is going to a middle lobe. The left lung only has upper and lower lobar (secondary) bronchi.
What is a bronchopulmonary segment (AKA tertiary bronchus)?
Where do tributaries of pulmonary veins pass in relation to bronchopulmonary (BP) segments?
Why are BP segments important?
How many BP segments does the right lung have? The left?
A bronchopulmonary segment is an area of lungsupplied by a segmental (tertiary) bronchus and its accompanying pulmonary artery branch.
Tributaries of the pulmonary veins tend to pass between bronchopulmonary segments.
A bronchopulmonary segment is the smallest, functionally independent region of a lung and the smallest area of lung that can be isolated and removed without affecting adjacent segments.
The right lung has 10 BP segments. The left lung has 8 BP segments.
How are the pulmonary tissues supplied with blood?
By bronchial arteries that arise the thoracic aorta or one of its branches.They are not supplied by pulmonary arteries or veins!
How are pulmonary tissues innervated? What kind of fibers do they contain?
The visceral pleura and other structures of the lung are innervated by GVA and GVE fibers distributed through the pulmonary plexus. These fibers originate from the vagus nerve and the sympathetic chain.
Describe the lymphatic drainage of the lungs.
The lungs drain into tracheobronchial nodes located around the roots of lobar and main stem bronchi and alongside the trachea. From here:
The right lung drains into right bronchomediastinal nodes and trunk.
The left lung drains into left bronchomediastinal nodes and trunk with the exception that the lower portion of the left lung drains into right bronchomediastinal nodes and trunk.
When looking at the carina on imaging, what may densities in this area be a sign of?
Densities in this area may be a sign of lung cancer (densities would be lymph nodes)
In what intercostal space is the horizontal fissure of the right lung located? How does this help with ausculation of the right lung?
It is located in the 4th intercostal space. When listening to the right lung anteriorly, this is how one differentiates btwn the upper and middle lobe.
Where is the best place to auscultate the inferior lobes of the lungs?
Posteriorly. Because of the oblique fissure, the lower lobes start up high in the body and lie more posteriorly.
