Anatomy Flashcards
Which ribs are the true vertebrosternal ribs?
ribs 1-7
Which ribs are the false (vertebrochondral) ribs?
ribs 8-10
Which ribs are the floating ribs?
ribs 11-12
What is the difference between vertebrosternal, vertebrochondral and floating ribs?
true ribs are bound to the sternum with costal cartilage at the costochondral joint
the costal cartilage of false ribs flows into costal margins that form the infrasternal (subcostal) angle. They do not articulate with the sternum
floating ribs have no costal cartilage and are only posteriorly attached to the vertbrae
What is the order of the intercostal neurovascular bundles (superior to inferior)?
V-A-N
[posterior] intercostal vein
[posterior] intercostal artery
intercostal nerve
where do the intercostal neurovascular bundles run on a rib (2)?
- beneath the inferior rim of the rib
- in the costal groove of the rib
where are blood, pus or pleural effusions usual found in the lungs (2)?
In the costodiaphragmatic and costomediastinal recesses
What is a pleural effusion
an abnormal collection of fluid in a pleural space.
*can be caused by cancer
When blood, pus or a pleural effusions collects in a costodiaphragmatic or costomedistinal recess, what symptoms are seen in the patient?
How is it treated?
dyspnea: difficulty breathing or shortness of breath
treatment: thoracentesis
Generally, how is a thoracentesis performed (2 steps)?
- locate collection on a CT/ultrasound
- tap the effusion with a needle (IOT draw the fluid out of the chest cavity/pleural space)
- patient will breath easier
When the pleural space is broken, air flows _1_ the chest wound instead of through the _2_. Why does this happen?
- into
- lungs
This happenes because of the negative and positive pressures generated in the ventilatory cycle
In exhalation, _1*_ in the lungs _2(increases/decrease), while _3*_ and _4*_ _5(increases/decrease).
*intrapleural pressures, tidal volume, intrapulmonary pressures
- tidal volume
- decreases
3-4. intrapulmonary/intrapleural pressures
- increases
what is a pneumothorax?
what is the effect of a pneumothorax?
air fills the pleural space between the lungs and chest wall
the lung collapses
what causes a sucking chest wound?
how do you treat a sucking chest wound (2 steps)?
pneumothorax
- treatment:
1. insert an emergency chest tube
2. place it on negative pressure (IOT re-expand the collapsed lung and drain blood)
IOT treat a sucking chest wound, insert a __1__ and place it on _2 (+/-)_ pressure IOT _3_ the collapsed lung and to _4_ the blood.
- chest tube
- negative
- re-expand
- drain
a chest tube is inserted through the layers of the _1_ space but close to the _2_ of the rib.
- intercostal
- superior margin
When in the field, how can you provide negative pressure for a chest tube?
- in the field, seal the end of the tube by tying it or taping it with a rubber glove
- if on the ward, place the end of the tube under water in a bottle that is below the level of the patient (ex. put the bottle on floor next to patient)
what are the muscles of the thoracic wall?
external intercostal
internal intercostal
innermost intercostal
transverse thoracis
diaphragm
How do external intercostal muscles attach to ribs? What is their main action?
They originate from the inferior border of a rib and insert on the superior border of the next rib. The point diagonally towards the center of the thorax/abdomen.
The action is to elevate ribs during forced inspiration
what is the attachment of the internal and innermost intercostal muscles?
what is their action?
- originate from the inferior border of ribs and insert on the superior border of the next rib. point away from the midline.
- the action during forced respiration is as follows:
- interosseous part: depresses ribs
- interchondral part: elevates ribs
where does the transversus thoracis muscle originate and attach?
what is its action?
what is it innervated by?
- the transversus thoracis muscle originates on the **posterior surface of the lower sternum ** and inserts on the internal surfaces of costal cartilages 2-6
- the action of the transversus thoracis muscle is to weakly depress the ribs
- it is innervated by the intercostal nerves
the internal thoracic arteries arise from which arteries? Where do they drain?
arise form the subclavian arteries. drain to the brachiocephalic vein.
At which thoracic vertebral levels do the inferior vena cava, esophagus and aorta penetrate the diaphragm?
“8-10-12”
IVC penetrates at T8
Esophagus penetrates at T10
Aorta at T12
How does the diaphragm contract? What is the result
Its domes are pulled inferiorly. As a result, the domes are flattened and abdominal viscera are pushed inferiorly therefore increasing the volume of the thoracic cavity and allowing more air into the lungs.
*also, blood in the IVC is pushed to the heart when the diaphragm contracts
describe the mvmts of the ribs and the sternum during respiration
ribs create a “bucket handle” mvmt
the sternum creates a “**pump **handle” mvmt
describe the mvmts of ribs during forced inspiration and force expiration.
in forced inspiration, the upper ribs moves up (bucket handle mvmt) and the lower ribs move out transversely IOT expand the thoracic cavity.
in forced expiration, the ribs move down and in.
what is dyspnea?
What are common causes of dyspnea?
what accomodation are made by the patient to breath?
- difficulty breathing, shortness of breath
- asthma, heart failure
- The patient will use accessorey respiratory muscles to help expand the thoracic cavity.
injury to the phrenic nerve will cause:
paralysis of half of the diaphragm (whether the R or L phrenic nerve is cut)
How do you diagnose a paralyzed diaphragm?
Radiographically or fluoroscopically.
During inspiration, the paralyzed dome will ascend as it is pushed up by the abdominal viscera (that are being compressed by the active dome).
During expiration, instead of ascending, the paralyzed dome withh descend due to the positive pressure of the lungs,
What are the branches of the aorta in order (3)?
brachiocephalic trunk (to the right)
left common carotid a.
left subclavian a.
what are the branches of the brachiocephalic trunk?
common carotid a.
subclavian a.
what are the branches of the subclavian artery?
vertebral a.
internal thoracic a.
thyrocervical trunk
axillary a.
the internal thoracic artery turn into which artery?
the superior epigastric artery
what are the six pleural layers and where are they located?
- visceral pleura: aronud the lung
- parietal pleura: lines the pleural cavity
- costal pleura: against the ribs
- diaphragmatic pleura: against the diaphragm
- mediastinal pleura: against the mediastinum (i.e. the heart and trachea)
- cervical pleura: top of the lung
what is the name of the lining of the thoracic cage?
endothoracic fascia
What is the difference between the hilum and the root of the lung?
the hilum is the dorrway while the root is the vessels and bronchi that go through th doorway and connect the lung to the mediastinum
what is contained in the root of the lung?
- pulmonary vessels (aa. and vv.)
- nerves
- bronchi
what are the five parts of the mediastinum?
- superior
- Inferior
- anterior
- middle
- posterior
what is located in the superior mediastinum (5)?
- thymus
- great vessels (SVC, arch of Azygos, arch of Aorta)
- trachea
- esophagus
- thoracic duct
what is located in the anterior (inferior) mediastinum (1)?
THE THYMUS
what is located in the middle (inferior) mediastinum?
- heart
- pericardium
- roots of the great vessels
what is in the posterior (inferior) mediastinum (4)?
- thoracic aorta
- thoracic duct
- esophagus
- azygous venous system
in a trauma patient, what does an abnormally widened mediastinum indicate?
a torn aorta
what is usually torn in a trauma patient when the aorta tears?
the ligamentum arteriosum
what is pneumothorax?
what is hydrothorax?
what is hemothorax?
entry of air into the pleural cavity
accumulation of fluid in the pleural cavity
blood entering the pleural cavity
- what is a thoracentesis?
- why is it performed?
- what level is it performd at?
- how is the needle angled?
- insertion of a hypodermic needle through an intercostal space into the pleural cavity
- to obtain a sample of fluid or to remove blood or pus
- the 9th intercostal space (superior to T10 IOT avoid the collateral branches)
- upward
- why is a chest tube inserted?
- where is the incision made for the tube?
- where is the tube inserted:
- for air removal?
- for fluid drainage?
- to remove large amounts of air, blood, serious fluid, pus
- the 5th or 6th intercostal space @ the midaxillary line (close to the nipple)
- to remove air: direct the tube superiorly toward the **cervical pleura. **To remove fluid, direct the tube inferiorly to the costodiaphragmatic recess
what does “coarctation of the aorta” mean?
a segment of the aorta is stenotic (narrow or constricted)
when is “coarctation of the aorta” usu diagnosed?
where does it usu occur?
congenital condition the exists at birth
usu in the thoracic aorta, distal from the branch of the L subcalvian artery
what is the result of “coarctation of the aorta”?
- enlarged intercostal arteries (IOT bypass the constriction and supply the LE)
- enlargement leads to notching and remodeling of the growing ribs
- notching leads to high blood pressure in the UE and **low **bp in the LE
How is coarctation of the aorta fixed?
it is repaired surgically
what is pectus excavatum? what usu causes it?
receding sternum (funnel chest)
overgrowth of ribs
what is pectus carinatum?
projecting sternum (pigeon breast- sticks/puffs out)
What is the defect in Poland syndrome?
- the pectoralis major (sternocostal head) and minor are absent
- incomplete sternal ossification leading to a hole or “sternal foramen”
how can you tell the difference between a congenital hole and a fracture?
a sternal foramen is smooth and not tender to the touch
this means it is not a fracture that has jagged edges and is tender to palpation
What are the levels of the right tracheobronchial tree?
- Trachea
- Right main bronchus
- Right superior lobar bronchus
- Right middle lobar bronchus
- Segmental bronchus
- Right lower lobar bronchus
What are the levels of the left tracheobronchial tree?
- trachea
- left ain bronchus
- left superior lobar bronchus
- left inferior lobar bronchus
What are the segments of the right superior lobe?
apical, posterior, anterior
what are the segments of the right middle lobe?
lateral and medial
what are the segments of the right inferior lobe?
superior, anterior basal, medial basal, lateral basal, posterior basal
what are the segments of the left superior lobe?
- apical, posterior (usu apicoposterior segment)
- anterior
- superior lingular
- inferior lingular
what are the segments of the left inferior lobe?
- superior
- anterior basal and medial basal (usu anteriomedial basal)
- lateral basal
- posterior basal
what are the three levels of brionchioles?
Conducting
Terminal
Respiratory
What are the tertiary structures of the bronchioles?
pulmonary artery
bronchiole
bronchial artery
name the next three levels after the terminal bronchiole
- respiratory bronchiole
- alveolar duct
- alveolar sac