Anatomy 3 Flashcards
(34 cards)
Where is the thoracic inlet? Transverse thoracic plane?
- In thorax - bounded by ribs 1, T1 vertebra and jugular notch
- Between sternal angle and T4/5 intervertebral disc
What is anterior mediastinum? What exists in anterior mediastinum? What diseases can affect this lymphoid organ? (3)
- Between sternum & the fibrous pericardium
- Thymus in CHILDHOOD (becomes replaced with adipose tissue after puberty)
- Thymoma, thymic carcinoma, lymphoma
What is present in middle mediastinum? (3)
1) pericardium
2) heart
3) parts of the great vessels that connect with the heart:
- inferior part of SVC
- superior part of IVC
- pulmonary trunk & pulmonary arteries
- pulmonary veins
- ascending aorta
What separates superior and inferior mediastinum? Is trachea part of posterior mediastinum?
- Sternal angle
* Posterior mediastinum is division of inferior mediastinum so trachea not part of it but primary bronchi are
What structures located within posterior mediastinum? (7)
- Primary bronchi
- Oesophagus
- Thoracic aorta
- Vagus nerves (difficult to isolate as form plexus on surface of oesophagus)
- Thoracic duct
- Azygous vein
- Sympathetic chains
Where is azygous vein located in relation to hilum? What can happen to azygous vein in trauma?
- Passes posterior to root of lung and drains anteriorly into SVC passing OVER root of lung
- Can be ruptured in trauma
What is thoracic aorta the same as? When does thoracic aorta become abdominal aorta?
- Descending aorta
* When passes through diaphragm
What are the mediastinal branches of the aorta?
- Ascending aorta - coronary arteries
- Arch of aorta - brachiocephalic trunk, left common carotid, left subclavian artery
- Thoracic aorta - bilateral posterior intercostal arteries, anterior branches of thoracic aorta
What are the anterior branches of thoracic aorta? (5)
- bronchial arteries (arterial blood for the lung tissue)
- oesophageal arteries
- mediastinal arteries
- pericardial arteries
- phrenic arteries (for the diaphragm
Where do anterior intercostal arteries arise from?
Internal thoracic arteries
What drains into right venous angle? Left venous angle?
What is a venous angle?
- right lymphatic duct drains lymph into right venous angle
- thoracic duct drains lymph into left venous angle
- Venous angle is formed between 2 veins - internal jugular and subclavian veins (form brachiocephalic vein)
How does lymph drain from the lungs? Exception?
- Lymph from bronchopulmonary/hilar lymph nodes drain into tracheo-bronchial lymph nodes into thoracic duct
- Exception - left lower lobe can sometimes drain back via right lymphatic duct rather than thoracic duct
Where are bronchopulmonary/hilar lymph nodes located? Tracheo-bronchial lymph nodes?
- Surround main bronchus at lung root
* Around bifurcation of trachea
What is specific position of thoracic duct in mediastinum? How is thoracic duct affected by trauma?
- Wedged between azygous vein and oesophagus
* Can be ruptured in trauma
What can mass in posterior mediastinum cause? (2)
- Can compress oesophagus causing dysphagia
* Can affect recurrent laryngeal nerves causing hoarseness
What is cisterna chyli?
Swollen start of throacic duct in abdomen
What is the difference between position of right vagus nerve and left vagus nerve in mediastinum?
- Right vagus nerve will pass on lateral surface of trachea, posterior to lung root, and follows oesophagus
- Left vagus nerve will cross arch of the aorta, posterior to lung root, then follows oesophagus
What is the recurrent laryngeal nerve? Where is left recurrent laryngeal nerve located? Right recurrent laryngeal nerve? What is the purpose of recurrent laryngeal nerves?
- Branch of the vagus nerve
- Hooks under arch of aorta (at ligamentum arteriosum) - DOES enter the chest
- Hooks under right subclavian artery - does NOT enter the chest
- Responsible for phonation (supplies the larynx)
How do phrenic nerves supply diaphragm? (2)
- Right phrenic nerve - passes through diaphragm with IVC to supply diaphragm from inferiro aspect
- Left phrenic nerve - pierces through left dome of diaphragm to supply it from inferior aspect
List branches in superior mediastinum from anterior to posterior (5)
Lateral to medial? (3)
Anterior to posterior
- brachiocephalic veins & SVC
- arch of aorta
- trachea
- oesophagus
- thoracic duct
Lateral to medial
- phrenic nerves
- vagus nerves
- recurrent laryngeal nerves
What are central veins? Examples? (7) What can they be used for?
Large veins close enough to the heart so the pressure within them reflects the pressure within the right atrium
- Internal jugular veins (JVP)
- Subclavian veins
- Brachiocephalic veins
- SVC
- IVC
- Iliac veins
- Femoral veins
Can be used for central venous cannulation (esp IJV)
What is normal range for JVP?
- At 45o JVP should be no more than 3cm superior to sternal angle
What nerves make up phrenic nerves? What are they somatic motor supply to? Somatic sensory? (4)
- Cervical spinal nerves C3, 4, 5
- Somatic motor to diaphragm
Somatic sensory
- mediastinal parietal pleural
- fibrous pericardium
- diaphragmatic parietal pleura
- diaphragmatic parietal peritoneum
What nerves make up phrenic nerves? What are they somatic motor supply to? Somatic sensory? (4)
- Cervical spinal nerves C3, 4, 5
- Somatic motor to diaphragm
Somatic sensory
- mediastinal parietal pleural
- fibrous pericardium
- diaphragmatic parietal pleura
- diaphragmatic parietal peritoneum
