Lecture 11: Thoracic Wall & Lungs Flashcards
Superficial to deep layers of the thorax
- Skin
- Superficial Fasica
- Muscles of upper limb
- Intercostal muscles
- Endothoracic Fasica
- Parietal pleura
- Thoracic cavity
Describe the transversus thoracic
Same “depth” as the innermost intercostals BUT is found on the anterior thoracic wall
Where do you find the transversus thoracis (I/O)
Sternum to 2nd-6th costal cartilages
What is the innervation of the thoracic wall?
Anterior rami of T1-T11 intercostal nerves
What is another name for the subcostal nerve?
T12
T/F: T12 innervates the thoracic wall
False - This is the subcostal nerve and it innervated the abdominal wall
What do you find in the intercostal space?
Intercostal VAN
The _______ branches of the intercostal vessels run in the costal groove, while the ________ branches run superior to the rib.
Main; collateral
Intercostal vessels supply blood to the…
thoracic wall
There are _____ anterior intercostal vessels
9
There are ____ posterior intercostal vessels
11
The anterior and posterior intercostal vessels do what?
Anastomose - form a vessel ‘arc’
Where do anterior and posterior intercostal vessels originate?
Aorta - descending aorta
Internal thoracic arteries are branches of ____________
subclavian artery
Where do you find internal thoracic arteries?
Along lateral side of sternum
What are the branches of the internal thoracic artery?
Anterior intercostal arteries (1st 6)
Musculophrenic artery (7th-9th anterior intercostal)
Superior epigastric artery (continuation of internal thoracic)
Superior epigastric artery anastomoses with…
Inferior epigastric artery
Posterior intercostal arteries
1 and 2 from supreme intercostal artery
Where do the branches of posterior intercostal arteries 3-11 come from?
Descending thoracic aorta
What are the veins of the thoracic wall?
Anterior intercostal veins –> internal thoracic vein
Posterior intercostal veins - describe them
Right: Azygos
Left: Hemiazygos
What are the boundaries of the thorax?
Superior thoracic aperture
diaphragm
sternum/costal cartilages
Thoracic vertebral bodies
What is the thorax divided into?
Central mediastinum and lateral pleural cavities
T/F: The lungs are in the mediastinum
False
The thoracic diaphragm is the boundary between…
Thorax and abodmen
T/F The diaphragm is only tendionus
F: Muscular and tendinous components
What is the primary muscle of respiration
Diaphragm
Label each of the following
- Central Tendon
- Aortic Opening (T12)
- Esophageal opening
- Caval opening (T8)
“I8 10 Eggs @ 12”
What is the innervation of the thoracic diaphragm?
L/R Phrenic Nerves (C3-5)
What is happening during inspiration?
Thoracic cavity is expanding
Vertical dimensions: diaphragm
Lateral dimensions: ribs
Anterior to posterior: sternum
What is happening during expiration?
Thoracic cavity is compressing
Vertical dimensions: diaphragm
Lateral dimensions: ribs
Anterior to posterior: sternum
__________ is a serous “sac” with 2 continuous membranes
Pleura
Describe the parietal pleura
Lines the thoracic wall
Describe the visceral pleura
Covers the lung
What is the space between the parietal and visceral pleura
Pleural cavity
Why is there serous fluid in the pleural cavity?
Lubrication and friction reduction
Describe a pleural effusion
When there is too much fluid in the lung and it makes it hard to breathe
If you have to remove fluid or pus from the thoracic cavity, where would you stick the needle – just superior to the rib or just inferior? Why?
Superior rib - it is better to hit collateral rather than main intercostal NAV
“Collateral damage”
Describe a Thoracocentesis
Draining fluid from pleural cavity (the space)
What is the blood supply to the parietal pleura
Same as thoracic wall
What is the innervation to the parietal pleura
Thoracic wall
What is the blood supply to the visceral pleura
Same as lungs [pulmonary and bronchial vessels]
What is the innervation to the visceral pleura
Same as lungs [ANS]
Describe the right lung
3 lobes (S, M, I)
2 Fissures (Horizontal, Oblique)
Describe the left lung
2 Lobes (S, I)
1 Fissrue (Oblique)
What is the lingula?
A structure in the L lung that is homologous to middle lobe of R lung
What are the surfaces of the lungs?
Costal
Diaphragmatic
Mediastinal
Costodiaphragmatic Recess
Costomediastinal Recess
Where does fluid start to collect in the lungs?
Costodiaphragmatic recess
Costomediastinal recess
What is the conducting portion of respiratory system made up of?
Larger tubes + passageways
Transports respiratory gases
NO GAS EXCHANGE HERE
Describe the respiratory portion of the respiratory system
Where gas exchange happens
Smallest tubes and air sacs (alveoli)
What is the order of teh conducting portion of the respiratory system
Trachea
L/R Main Bronchi
Lobar Bronchi
Segmental Bronchi
Bronchi
Bronchioles
Terminal Bronchioles
Describe the trachea
Connects to Larynx superiorly
Travels from the neck to the thorax
Splits into L/R primary bronchi
What cartilage is found in the trachea
C-shaped hyaline cartilage
Where do you find irregular plates of cartilage in the respiratory system?
L/R Primary Bronchi
If you accidentally inhale something, which primary bronchus would you expect it to go in to?
Right is more likely (3 lobes, increased diameter, straight down)
Where do you find cartilage plates in the conducting portion of the respiratory system?
Secondary (lobar) bronchi
What supplies one bronchopulmonary segment of the lung
Tertiary (segmental) bronchi
What are Bronchopulmonary segments
Supplied by a single tertiary bronchus, artery and vein, lymphatic vessels and nerves
Each is surrounded by CT and is a division of a lung lobe
Why are bronchopulmonary segments important?
Each segment has its own “thing”, i.e. segments can be removed due to pathology.
