Week 8 Flashcards
State the motor and sensory supply of the diaphragm, including root values
Phrenic nerves, from C3, C4 & C5 (keep the diaphragm alive)
State the anterior attachments of the diaphragm
Xiphoid process
Shafts and costal cartilages of ribs 7-12
State the posterior attachments of the diaphragm
Left crus attaches to L1 & L2 vertebral bodies
Right crus attaches to L1, L2 & L3 vertebral bodies
Median arcuate ligament attaches to T12 vertebra
Medial arcuate ligament attaches to tip of L1 transverse process and L1 vertebral body
Lateral arcuate ligament attaches to tip of L1 transverse process & 12th rib
What structures pass through the diaphragm at T8?
Superior Vena Cava & right phrenic nerve
left phrenic passes through the central tendon
What is the arterial supply to the diaphragm?
Superior & inferior phrenic arteries
Which part of the diaphragm does not move inferiorly during inspiration? Why?
Both right and left domes descend during inspiration
The central tendon of diaphragm does not moves because it is attached to the fibrous pericardium
State the different parts of parietal pleurae and their locations
Cervical pleura: above the thoracic inlet (T1 & 1st ribs and CCs)
Costal pleura: in contact with the thoracic wall
Diaphragmatic pleura
Mediastinal pleura: in contact with the pericardium & mediastinal structures
What are the 2 pleural recesses?
Costodiaphragmatic recess
Costomediastinal recess
(recesses are potential spaces & the sites of fluid accumulation)
What structures pass through the diaphragm at T10?
just left of the midline through the right crura
Oesophagus
Right & left vagus nerves
Left gastric vessels
What structures pass through the diaphragm at T12? (behind the median arcuate ligament)
Aorta
Thoracic duct
Azygos veins
Explain the general process of inspiration & expiration
Inspiration is caused by contraction of the diaphragm & external intercostals, increasing thoracic volume & creating a negative intrathoracic pressure, causing air to rush into the lungs
Expiration is caused by elastic recoil of muscles & recoil of compressed abdominal organs
What is the movement of the ribs during quiet inspiration?
Pump-handle movement, moving the sternum forwards, increasing antero-posterior diameter of the thorax, and also lateral diameter
What is the movement of the ribs during forced inspiration, which ribs move and why?
Bucket-handle movement, increasing lateral thoracic diameter
Only in ribs 8, 9 & 10 due to their flat costo-transverse joint allowing a gliding movement
Describe the boundaries of the pleura and lungs
Pleura:
Apex is 2cm above the medial third of the clavicle
Moves down almost to the midline at 2nd CC
- In the left lung, pleura goes from 2nd CC to 4th CC, then laterally to 6th CC (to make space for the heart)
- In the right lung, the pleura moves straight from 2nd CC to 6th CC
- Then both, from 6th CC:
to 8th rib, mid-clavicular line
10th rib, mid-axillary line
12th rib, mid-scapular line
Lungs:
Largely follow the pleural boundaries, except the bottom of the lungs are 2 ribs above the bottom of the pleurae
Define pneumothorax
Breaching of pleura allowing air into the thorax, creating a space around the lung at higher pressure than within the lung
Thus the lung shrinks
