Anatomy 3 Flashcards
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
Can can cause referred pain from the diaphragm? How does it cause diaphragmatic pain?
- Liver abscess or inflammation of gallbladder
* Irritates parietal peritoneum lining surface of diaphragm supplied by phrenic nerve C3, 4 and 5
Where is diaphragmatic pain often referred? Why?
Shoulder tip
- Supraclavicular nerves C3 and 4 supply dermatomes of shoulder tip and enter spinal cord at same level as phrenic nerve (C3, 4, 5)
- Brain refers pain to more superficial structure - skin over shoulder tip
Wat do vagus nerves contain? What do recurrent laryngeal nerves supply?
- Somatic sensory nerves - for plate, laryngopharynx + larynx
- Somatic motor nerves - for pharynx + larynx
- Autonomic parasympathetic nerves - for thoracic and abdominal organs
Recurrent laryngeal nerves - branches of vagus nerve that supply pharynx + larynx
What structures does cephalic vein drain? Axillary artery and vein drain/supply? Subclavian artery/vein? Internal thoracic artery/vein? Anterior and posterior intercostal arteries?
- Cephalic vein - upper limbs
- Axillary artery/vein - axilla
- Subclavian artery and vein - arms
- Internal throacic artery/vein - anterior body wall
- Anterior and posterior intercostal arteries - intercostal spaces
What structures does great saphenous vein drain? Internal iliac? External iliac? Femoral artery/veins?
- Great saphenous - leg
- Internal iliac - pelvis
- External iliac - lower limb
- Femoral - thigh and leg
What does ophthalmic artery supply? Central artery of retina?
- Ophthalmic artery - eye
* Retina
Where is bifurcation of common carotid auscultated? What is it auscultated for?
- Anterior to sternocleido-mastoid muscle at level of superior border of thyroid cartilage
- Bruits - indicate turbulent blood flow due to carotid artery disease
Where is brachial artery palpated? Radial artery? Femoral artery? Popliteal artery?
- Medial to biceps brachii tendon in cubital fossa
- Lateral to tendon of flexor carpi radialis
- Inferior to midpoint of inguinal ligament
- In popliteal fossa
Where is posterior tibial artery palpated? Dorsalis pedis artery?
- Posterior border of medial malleolus
* Medial to tendon of extensor hallicus longus
What is subclavian artery used medically for? Radial artery? IJV? Femoral vein?
- Subclavian artery - insertion of cardiac pacing wire under ultrasound guidance
- Radial artery - cannulation for arterial blood pressure monitor/ABG sampling
- IJV - insertion of central line under ultrasound guidance
- Femoral vein - insertion of central line
