Dissection of the Lungs and Pleura Flashcards
What fissures are in the right and left lung?
- right = oblique and horizontal fissure - left = oblique fissure
What does the horizontal fissure separate in the right lungs?
- separates right middle lobe from the right upper lobe.
What does the oblique fissure separate in the left and right lungs?
- left = separates upper and lower lob - right = separates inferior from middle and upper lobe
What does the apex and base of the lung refer to?
- base = bottom - apex = top
When performing dissection, the cadaveric lungs appear shiny, why is this?
- due to visceral pleura
Where is the superior and inferior pulmonary vein when looking at the medial surface of the lungs?
- inferior = lowest blood vessel, close to pulmonary ligament
- superior = above inferior in the D of the hilum
- both veins are below the pulmonary arteries
Where is the pulmonary artery when looking at the medial surface of the lungs?
- superior to pulmonary veins
- top of hilum
What are the contents of the lung root?
- pulmonary veins (pair) - pulmonary arteries (pair) - nerves - principle/primary bronchi - lymphatics
The parietal pleura is innervated by somatic nerves, what does this mean for what the parietal pleura is able to feel?
- somatic relates to senses
- pain
- temperature
- irritation
When looking at the medial surfaces of the lungs, which lung will the impression of the aortic arch be in?
- left lung
The visceral pleura is innervated by autonomic nerves, what does this mean for what the visceral pleura is able to feel?
- stretch of the lungs only
- Hering-Breuer reflex when tidal volume is 3 times normal
When looking at the medial surfaces of the lungs, which lung will the largest cardiac impression?
- left lung
Which lung will have the impression of the inferior and superior vena cava?
- right lung
What does the term lung root mean?
- structures entering/leaving the lung
What does hilum refer to in the lungs?
- hollow site on surface of an organ
- allows vessels and nerves to flow in/out
- lung root enters/leaves here
Why are pulmonary arteries higher than pulmonary veins in the lung root?
- pulmonary arteries leave heart from pulmonary trunk
- pulmonary veins return to left atrium
- piulmonary trunk is higher than left atrium
Where is the lingula located?
- left lung only - referred to as the tongue - located medial/inferior part of lung
On the medial surfaces of the lungs is the oesophagus impression on the left or right lung?
- right lung
- deviates to the right due to heart
In addition to the aortic arch impression on the left lung, what other impression, cardiac wise is visible on the left lung?
- descendcing aorta
Which 2 cavities does the diaphragm seperate?
- thoracic cavity - abdominal cavity
What type of muscle is the diaphragm and what nerve innervates this muscle?
- skeletal muscle - phrenic nerve
Which spinal cord segments give rise to the phrenic nerve?
- C3, 4 and 5 - keeps us alive
How is it possible to distinguish between the phrenic and vagus nerve on an image?
- vagus nerves runs posterior to base of the lung
- phrenic nerves runs anterior to base of the lung
- vagus tends to run closer to spinal cord
What is the light coloured region of the diaphragm?
- central tendon
When supine (lying on your back) why does thoracic cavity capacity decrease?
- organs push on diaphragm - diaphragm raises to 5th intercostal space
When in the anatomical position is the diaphragm higher or lower in the thoracic cavity when compared to being supine?
- diaphragm is lower (6-7th intercostal space) - abdominal organs drop due to gravity
Where are the internal thoracic arteries and what do they supply?
- runs on anterior of the chest
- supplies blood to breasts, parietal pleura, sternum, pericardium and thymus
Where are the pericardiophrenic arteries, and what do they supply?
- posterior to internal thoracic arteries
- branch of internal thoracic artery
- aligns with phrenic nerve
- supplies pericardium and diaphragm
The primary/principle bronchi begins where?
- carina - trachea splits into left and right here
What is the main role of the primary/principle bronchi?
- carry air from trachea to secondary bronchi
The larynx is made up of 4 main components, what are they, and what is the order from superior to inferior?
1 - epiglottis
2 - thyroid cartilage /Adam’s apple
3 - cricoid cartilage
4 - tracheal rings
What is the bone that separates the epiglottis and the thyroid cartilage?
- hyoid bone - part of axial skeleton
The parietal pleura can be divided into 4 sections depending on which part of the lungs it is facing. What are the 4 sections?
1 - mediastinal 2 - diaphragmatic 3 - cervical 4 - costal
What nerves supply the costal pleura aspects of the parietal pleura?
- intercostal nerves
What nerves supply the mediastinal pleura aspects of the parietal pleura?
- phrenic nerve
What is a pneumothorax?
- air within the pleural space
- causes a collapsed lung
- sudden, generally due to traume
Using Boyles Law (⬆️ Pressure = ⬇️ Volume) what can a pneumothorax cause in the lungs?
- air in pleural space = ⬆️ pressure - ⬆️ = ⬇️ volume - ⬇️ volume could collapse the lung
What is a pleural effusion?
- fluid in pleural space
What are the 2 different types of pleural effusion?
- transudate - exudate
What does exudate mean in relation to a pleural effusion?
- ex means to leave - fluid leaking out of the lung
When analysing exudate in a pleural effusion, how would we know if the fluid was exudate and not transudate?
- exude has ⬆️ protein content - exude has ⬆️ lactate dehydrogenase content
What are some common causes of an exudate in a pleural effusion?
- local effects
- inflammatory response
- lung cancer
- pneumonia
- TB and other infections
What does transudate mean in relation to a pleural effusion?
- trans means to move across - fluid leaves the lungs
What are some common causes of an transudate in a pleural effusion?
- pressure changes (hydrostatic/osmotic) - congestive heart failure - hypoalbuminemia - hypothyroidism
What can a pleural effusion do to the lungs?
- lungs space is ⬇️ due to fluid - ⬇️ lung volumes - can cause trachea deviation
Where is the costodiaphragmatic recess, also called the costophrenic recess?
- point where costal and diaphragmatic aspects of parietal pleura reflect (bend) - interior lateral aspect of parietal space
What is the function of the costodiaphragmatic recess, also called the costophrenic recess?
- dead/reserve space in thoracic cavity - allows for forced inspiration - never truly fills
Where is the costomediastinal space?
- point where costal and mediastinal aspects of parietal pleura reflect (bend)
What is the function of the costomediastinal space?
- dead/reserve space in thoracic cavity - allows for forced inspiration
What is the anatomical landmarks on the chest that can be used to identify the oblique fissure?
- 6th rib around chest wall
If a patient has a pleural effusion or pneumothorax which needs to be drained, what is the site for this?
- costodiaphragmatic recess is where fluid collects
- the triangle of safety
- lateral border of pec major anterior
- lateral border of lat dorsi posteriorly
- inferiorly, by a horizontal line from the nipple (commonly the 5th intercostal space)
When performing a drain from the lung which part of the lung is the triangle of safety over?
- costodiaphragmatic recess, also called the costophrenic recess as fluid gathers here due to gravity
What does bronchi and bronchus mean?
- bronchi = >1 - bronchus = 1
What does oblique mean?
- not running horizontal or parallel
- runs diagonally
