Lecture 2 - Thorax, Lungs, and Pleura Flashcards
What are the 3 functions of the thoracic wall?
- Protection (also protects liver and kidney not just heart and lungs)
- Muscle attachment
- Facilitates breathing
What are the components of the thoracic skeleton (4)?
What are the 3 components of the sternum
- Manubrium
- Body
- Xiphoid
What is the important landmark of the sternum
Sternal angle
What is the jugular notch?
The top of the manubrium
What is the name of the joint between the xiphoid and the body of the sternum called?
Xiphisternal joint
What are the 8 landmarks represented by the sternal angle
What are the true ribs
What are the false ribs
What are the floating ribs
What is the superior thoracic aperture and what 3 structures is it bound by?
What is the inferior thoracic aperture and what 3 structures is it bound by and 1 structure that it is closed by
Movement of ribs during inspiration [increases/decreases] thoracic volume
Increase
Describe the movement of the upper and lower ribs during respiration
What are the 3 muscles of respiration
- Diaphragm
- Intercostal muscles
- Accessory muscles
What are the 4 functions of the diaphragm
- Main muscle of inspiration
- Separates thoracic and abdominal cavities
- Increases thoracic volume and intra-abdominal pressure when contracting (pushes abdominal cavity down to increase thoracic volume allowing air to rush in for respiration to take place)
- Positioning of the diaphragm depends on phase of respiration, standing, or supine, and distention of abdominal viscera
What are the 3 holes in the diaphragm
- Caval opening (T8)
- Esophageal hiatus (T10)
- Aortic Hiatus (T12)
What does the caval opening (T8) in the diaphragm transmit (2)
- Inferior vena cava
- Right phrenic nerve
*I8
What does the esophageal hiatus (T10) transmit (2)
- Esophagus
- Anterior and posterior trunks of vagus
*10 eggs
What does the aortic hiatus (T12) transmit (3)
- Aorta
- Azygous vein
- Thoracic duct
What are the 3 intercostal layers
- External
- Internal
- Innermost
What are 4 characteristics of the external intercostals
What are the 4 characteristics of the internal intercostals
What are the 2 characteristics of the innermost intercostals
What are the 5 accessory muscles of the ribs
**Note serratus posterior is not in image because its on the posterior aspect
What nerve (and cervical branches) is involved in the sensory and motor innervation of the diaphragm
Phrenic nerve (C3, C4, C5 keeps the diaphragm alive)
What is the 3 major blood supplies of the diaphragm
- Internal thoracic artery -> branches into pericardiophrenic arteries and musculophrenic arteries
- Thoracic artery -> branches into superior phrenic arteries
- Abdominal aorta -> branches into inferior phrenic arteries
What is the 2 major blood supplies to the thoracic wall and their branches
What does the internal thoracic artery also supply
Skin, fascia, muscles and bones
What is the neurovascular bundle formed by and where is it found
Neurovascular bundle is formed by the intercostal vein, artery, and nerve which lie in the costal groove found on inferior surface of the ribs
Is the vein, artery or nerve most likely to get damaged in the neurovascular bond of the intercostals and why?
Nerve is most likely to get damaged because it is in the muscular region and is not protected by the intercostal groove
What is the location of the lungs and pleura
They are 2-3 cm into root of neck, contacted by diaphragm inferiorly and lateral to mediastinum (heart, great vessels, esophagus and trachea), and are protected by the thoracic skeleton (ribs, sternum, thoracic vertebrae, clavicle)
What is the relationship between lungs and pleura
Lungs are outside of, but surrounded by the pleural sac
What are the 2 layers of the pleural sac and what do they line
Pleural cavity
Potential space between parietal and visceral layers that is filled with serous fluid
What are the 4 regions of the parietal pleura and what do they cover
What is the visceral pleura
The pleura that surrounds the lungs
What are the lines of pleural reflection
These are spaces that create recesses based on where the lungs and pleura turn
What are the 2 recesses between the lungs and pleura and their location
What are the 3 lines we anatomically use to divide the chest during palpation
- Mid-clavicular line
- Mid-axillary line
- Vertebral line
What rib does the pleura and lung of the mid-clavicular align with
Pleura - 8th
Lung - 6th
What rib does the pleura and lung of the mid-axillary line align with
Pleura - 10th
Lung - 8th
What rib does the pleura and lung of the vertebral line align with
Pleura - 12th
Lung - 10th
What are fissures in the lungs
They separate the lobes
What are the 4 surfaces of the lungs
- Costal
- Diaphragmatic
- Mediastinal
- Apex
How many lobes is in the right and left lungs and what are the 2 fissures of the lungs
What is the hilum and what 4 structures enter through it
Label the right lung at hilum
Label the left lung at hilum
The trachea is made up of what 2 things
- Cartilaginous rings anteriorly
- Trachealis (muscle) posteriorly
What is the name of where the trachea divides into the right and left bronchi
Carina
Why is the trachea made of muscle posteriorly
Esophagus is posterior to trachealis and needs to be musculature to allow esophagus to bulge when we eat to allow food to make its way down. If not we would cause compression against cervical spine.
Describe the structure of the bronchi and what it is broken up into structurally
