VIVA: Anatomy - Thorax Flashcards
Describe the course of the thoracic aorta
Ascending aorta *:
- Begins at aortic orifice
Arch of aorta *:
- Begins behind sternocostal junction, passes supero-posteriorly and to the left anterior to the right pulmonary artery and the carina
- The apex of the arch lies to the left of the trachea/oesophagus and descends posterior to the left lung root, ending back to the level of the T4 (2nd sternocostal joint)
Descending aorta *:
- Origin is at the left side at the level of the T4 vertebra
- Courses inferiorly to the level of T12
- It approaches the midline as it descends alongside the oesophagus
- At the inferior border of T12 it exits through the aortic hiatus * and becomes the abdominal aorta
*needed to pass
Outline the structures that make up the right and left cardiomediastinal borders on this XR
6/10 to pass:
Right cardiomediastinal border:
- Right brachiocephalic vein
- SVC
- Right pulmonary trunk
- Right atrium
- IVC
Left cardiomediastinal borders:
- Left subclavian artery / left brachiocephalic vein
- Aortic arch
- Left pulmonary trunk
- Left atrial appendage
- Left ventricle
Describe the lobes of the lungs and their fissures
Both lungs:
- Oblique fissures * from T2 posteriorly to 6th costal cartilage anteriorly separate upper and lower lobes
Right lung *:
- Transverse fissure * at level of right lung hilum along line of 4th rib separates upper and middle lobes
Left lung:
- Prominent cardiac notch in lower lobe with lingula below
*needed to pass
What part of the lung forms the right heart border?
Right middle lobe
Describe the expected positions of the fissures of the lung on a normal CXR
- Right lung has 3 lobes, left has 2 lobes
- Oblique fissures separate the upper from lower lobes, and horizontal fissure separates the right upper and middle lobes
- Oblique fissures* follow the 5th ribs (run from 4th thoracic vertebrae to 3cm posterior of the junction between the diaphragm and the sternum on the left, and to the sternodiaphragmatic junction on the right)
- Horizontal fissure on right* at level of 4th costal cartilage or hilum
*needed to pass (within 1 space either way)
Describe the position of the neurovascular structures in the intercostal space
- Between the middle and innermost layers, protected by the costal groove of the superior rib of each intercostal space
- Ordered vein, artery, nerve from superior to inferior
When placing an intercostal catheter (ICC) in the 5th intercostal space laterally, what anatomical structures are traversed?
- Skin
- Subcutaneous tissues
- External intercostal muscle*
- Internal intercostal muscle*
- Innermost intercostal muscle*
- Parietal pleura
*2 needed to pass
What structures may be at risk from an ICC inserted laterally?
- Neurovascular bundle*
- Long thoracic nerve* (lies in serratus anterior behind the mid-axillary line)
- Lung*
- Diaphragm*
- Pericardium/heart* and spleen if on left
- Liver* if on right
*2 to pass
Which lobes of the lung lie adjacent to the right and left cardio-mediastinum?
Right upper mediastinum:
- Right superior lobe
Right heart border *:
- Right middle lobe *
Left upper mediastinum:
- Left superior lobe
Left heart border *:
- Left superior lobe * (lingula segment)
*needed to pass
What are the boundaries of the lung lobes? Demonstrate the lobes on this XR
- R and L UL fill apices/upper zones *
- Lingula abuts L heart border
- L LL abuts L hemidiaphragm *
- R LL abuts R hemidiaphragm *
- R ML abuts R heart border *
*needed to pass
Describe the surface anatomy of the parietal pleura
- Supraclavicular fossa
- Medially follow the middle of the sternum to the level of 6th costal cartilage
- Deviates laterally reaching 8th rib in midclavicular line, 10th rib in midaxillary line, and 12th rib at paravertebral line
- Notch on left
In a patient who has sustained blunt trauma in a motor vehicle accident, what injuries may be seen on a CXR?
Chest wall*:
- Rib fracture
- Clavicular fracture
- Sternum fracture
Lung*:
- Pneumothorax
- Haemothorax
- Pulmonary contusion
Cardiovascular:
- Damage to aorta or other great vessels (widened mediastinum)
Identify this bone and demonstrate its features
- First rib*
- Left* (determined by identifying superior surface)
- Broadest, flattest, shortest rib
- Lies nearly horizontal, with wide body
- Groove for subclavian artery*
- Features include head, neck, tubercle, shaft, single facet on head for articulation with T1 vertebra only
- On superior surface, from neck to tip: groove for subclavian artery and lower trunk of brachial plexus (posterior to artery), scalene tubercle and ridge for attachment of scalenus anterior, groove for subclavian vein, flat out surface for attachment of first digitation of serratus anterior, attachments to costoclavicular ligament (inner) and subclavius (outer)
- Tip articulates with costal cartilage
*needed to pass + 2 other features
Describe the neurovascular relations of the first rib
Nerves:
- C8 nerve root above and T1 nerve root below unite to form the lower trunk of the brachial plexus, which sits above rib surface behind subclavian artery
- Sympathetic trunk (cervicothoracic ganglion) in contact with anterior border of neck
Vessels:
- Subclavian artery* runs in groove behind scale tubercle, touching outer border of rib
- Subclavian vein runs anterior to scalene tubercle, in its own groove
- First intercostal neurovascular bundle beneath the undersurface, covered by parietal pleura
- needed to pass + 1 nerve
What are the important relations of the first rib?
- Apex of lung*
- Subclavian vessels*
- Intercostal vessels and nerves
- Sympathetic trunk
- Lower trunk of brachial plexus (superior to rib)
- Scalenus anterior/medius
- Intercostal muscles
- Serratus anterior
- Subclavius
*needed to pass
Identify the great vessels and branches which enter and exit the heart on this model
- SVC* with right and left brachiocephalic veins
- IVC*
- Ascending aorta* with brachiocephalic trunk, L common carotid artery and L subclavian artery
- Pulmonary trunk* and pulmonary arteries
- Pulmonary veins
Identify the chambers and valves of the heart on this model
To pass:
- Right atrium
- Left atrium
- Right ventricle
- Left ventricle
- Tricuspid valve
- Mitral valve
- Aortic valve
- Pulmonary valve
Demonstrate on this model the arterial supply of the heart
Coronary arteries arise from the aortic sinuses:
- Right coronary artery *: gives off SA nodal branch (in 60%), right marginal branch, AV nodal branch, posterior interventricular (in 66%), and interventricular septal
- Left coronary artery *: gives off circumflex artery * which branches to give the SA nodal artery in 40%, left marginal artery, posterior interventricular (in 15%), and LAD
- Left anterior descending: from left coronary artery (supplies anterior 2/3 of septum), gives off lateral diagonal branches
*needed to pass
Using the CXR, name and indicate the position of the lobes of the lung
- Right and left upper lobe fill apices/upper zones*
- Lingular lobe abuts left heart border
- Left lower lobe abuts left hemidiaphragm*
- Right lower lobe abuts right hemidiaphragm*
- Right middle lobe abuts right heart border*
*needed to pass
What are the anatomical structures to consider when inserting a lateral intercostal catheter?
- Above the rib below* to avoid neurovascular bundle
- Above 5th-6th intercostal space* to avoid diaphragm
- Anterior to mid-axillary line or latissimus dorsi
- Posterior to pectoralis major
*needed to pass + 1 other
