Recap lectures 8-9 (thorax) Flashcards
Thorax and mediastinum
What are the two main parts of the pulmonary cavity?
1) Viscera: primarily lungs, vessels, airways
2) Pleura: Pleural cavity
What are the two main types of pleura found in the thoracic cavity?
Parietal and visceral
1) What is the sternal angle (manubriosternal joint)?
2) What spinal level is it at?
3) What is found here?
1) 2nd rib articulation and connection between manubrium and body of sternum
2) T5
3) Bifurcation of the trachea; base of the heart/root of the ascending aorta
What property is conveyed by the costochondral cartilages? Why?
Flexibility, prevent traumatic fx,
Describe the thoracic inlet and thoracic outlet
1) Thoracic inlet: trachea, esophagus, vessels and nerves
2) Thoracic outlet: closed by diaphragm; IVC, esophagus pass through diaphragm, aorta passes posterior to diaphragm
1) Describe flail chest
2) Is it painful? What does this cause?
1) Multiple rib fractures cause paradoxical wall movement
2) Painful to breathe in, which causes poor ventilation & leads to atelectasis
What causes thoracic outlet syndrome?
Compression of structures between 1st rib and clavicle
List the 8 parts of the sternum
1) Manubrium: upper section of sternum
2) Clavicular notch: superior lateral notches of manubrium
3) Jugular notch: superior medial notch of manubrium
4) Costal cartilage: lateral part of manubrium
5) Costal notches: lateral notches of body
6) Sternal angle: The manubriosternal joint
7) Body: general longer part
8) Xiphoid process: inferior small piece attached to body
What 3 types of muscles can be involved with inhalation?
1) Intercostals
2) Diaphragm
3) Accessory
1) How many pairs of thoracic spinal nerves are there?
2) What do their posterior rami innervate?
1) 12
2) Bones, joints, intrinsic back mm., and over lying skin (dermatomes)
What are the two things formed by the thoracic spinal nerve anterior rami?
1) Anterior rami T1-11: forms intercostal nerves
2) Anterior rami T12: forms subcostal nerve
What is the order of the vessels and nerve in each rib from superior to inferior?
V.A.N (vein, artery, nerve)
1) Where should thoracentesis be performed? Why?
2) What is done during this procedure?
3) Why?
1) To avoid injury to intercostals, go over top of rib, high enough to avoid collaterals.
2) Collect pleural fluid sample for analysis
3) Therapeutic
What space is the chest tube once
appropriately placed?
4th intercostal space, at the mid clavicular line
What are the 4 main arteries that supply the thoracic wall?
1) Posterior intercostal arteries
2) Internal thoracic artery
3) Anterior intercostal arteries (2)
4) Subcostal arteries
1) Where does the internal thoracic artery come from?
2) What two things does it divide into?
1) Subclavian artery
2) Musculophrenic and superior epigastric arteries
Where does the subcostal artery come from?
Aorta
What provide blood to the intercostal space?
1) Posterior intercostal arteries + collateral br.
2) Anterior intercostal arteries + collateral br.
How many thoracic veins are there?
1) 11 pairs intercostal veins
2) 1 pair subcostal veins
1) What do the posterior IC veins anastomose with?
2) What do most posterior IC veins drain into?
1) Anterior IC veins.
2) Azygos/hemi-azygos venous system to SVC
1) What are the lactiferous ducts?
2) What is the lactiferous sinus?
1) Drains each lobule, open independently on the nipple
2) Dilated portion of each lactiferous duct just deep to areola
List all 6 mammary gland structures
1) Nipple
2) Areola
3) Lobules
4) Lactiferous duct
5) Lactiferous sinus
6) Suspensory ligaments
With mastitis, what directions can infection spread?
Superiorly, laterally, or medial to the breast
Where does most drainage from the lymphatic plexus of the breast go? What %?
75% to axillary nodes (pect., central, & apical nodes)
1) Where do the medial breast quadrants drain?
2) Where may the inferior quadrants pass?
1) Parasternal nodes or contralateral breast
2) Deeply to abdominal lymph nodes
What are some visual symptoms of BC
1) Skin dimpling
2) Edema
3) Nipple retraction and deviation
4) Abnormal contours
1) What do the right and left pulmonary cavities contain?
2) What is between the parietal and visceral pleura?
1) Lungs and pleura
2) Pleural cavity
What 6 things are found within the mediastinum?
1) Heart
2) Great vessels
3) Trachea
4) Esophagus
5) Thymus
6) Lymph nodes
What are the 4 parts of the parietal pleura?
1) Apical or cervical pleura
2) Costal pleura
3) Diaphragmatic pleura
4) Mediastinal pleura
What does the parietal pleura cover?
Endothoracic fascia/wall
What do the parietal and visceral pleura of the visceral cavity create?
Pleural “space” or sac
List the lobes of the right lung and what separates each
1) Superior lobe
-Horizontal fissure
2) Middle lobe
-Oblique fissure
3) Inferior lobe
-Has costodiaphragmatic recess
List the lobes of the left side of the lung and what separates them
1) Superior lobe: lingula
-Oblique fissure
2) Inferior lobe
What muscles are recruited during times of increased respiratory effort?
Scalenes and SCM
What separate the breast from the underlying pectoral muscles?
1) SQ tissue
2) Retromammary space (bursa)
3) Pectoral fascia
1) What ribs articulate directly with the sternum?
2) What about via the costal arch?
3) What ribs are floating?
1) First 7 ribs (“true ribs”)
2) 8-10
3) Ribs 11 & 12
Where does most blood supply to the breasts come from? Know where the branches come from.
1) Medial mammary branches of perforating branches and anterior intercostal branches of the internal thoracic artery: originate from the subclavian artery
2) Mammary branches of lateral thoracic and thoraco- acromial arteries: branches of the axillary artery
3) Posterior intercostal arteries: branches of the thoracic aorta that run in the intercostal spaces
Describe the dermatomes of the neck and trunk
1) C1: inferior neck
2) C3: clavicle
3) C4: includes top of shoulder
4) T2: below C4 on thorax
5) T3-12 until L1
>T5 is where the male nipple is
Describe the basic process of lactation
1) Lobules of mammary gland grow and fill up
2) Lactiferous ducts confer milk to the nipple, passing through the lactiferous sinus just before reaching it
Normally lungs are radio_________ and vessels will be more radio________
radiolucent; radiopaque
What supply each segment of the lungs with air, blood to oxygenate, and drainage of blood?
1) Segmental bronchus (air)
2) Tertiary branch of pulmonary artery (blood)
3) Intersegmental parts of pulmonary vein (blood drainage)
What are the bronchopulmonary segments important for?
Lung segment resection (cancer, copd, etc)
What part of the lungs can you find superior to the clavicle?
Cervical pleura and apices of lungs
1) List how many costal cartilages there are on the right side
2) List how many there are on the left side
1) 2-6 on right
2) 2-4 on left
1) What fissure does the right lung have that the left doesn’t?
2) Where is it?
1) Horizontal fissure
2) Extends from oblique fissure along 4th rib and costal cartilage anteriorly
What are the two main vessels involved in pulmonary circulation?
1) Pulmonary artery
2) Pulmonary vein
1) What does the pulmonary artery arise from?
2) What does it divide into within each lung?
3) What does that divide into after that?
4) What kind of blood does it carry?
1) Pulmonary trunk (left and right)
2) Lobar arteries
3) Segmental arteries
4) Poorly oxygenated blood
Describe the route of the right pulmonary artery
Passes underneath aortic arch and posterior to SVC
1) What pleura is insensitive?
2) What pleura is sensitive? What condition is this associated with?
1) Viscera pleura
2) Parietal pleura very sensitive to pain; “pleuritis”
1) What arteries supply the lung tissues and structures?
2) Is the blood deoxygenated or oxygenated?
3) Where does the left one arise from?
4) Where does the right one arise from?
1) Bronchial arteries
2) Oxygenated
3) Aorta
4) Right varies
1) What do bronchial veins drain? Where do they drain into?
2) What do pulmonary veins drain?
1) Only proximal parts [of lungs] into azygos vein
2) More distal tissue
What is the significance of one main stem bronchi being shorter and wider than the other? (2 reasons)
1) Right main stem is a common place for foreign body or GI aspiration
2) Right main E-tube placement
Most post ganglionic sympathetic nerves are ______adrenergic/ cholinergic__________
adrenergic (relating to epinephrine)
Most pre ganglionic neurons are ______adrenergic/ cholinergic__________
cholinergic (relating to acetylcholine)
1) What is the primary muscle of respiration?
2) Which part descends during respiration?
3) Which part is higher on one side than the other?
4) How many openings does it have?
1) Diaphragm
2) Central portion
3) Right dome higher than left dome
4) 3 hiatal openings
1) Where is the caval opening?
2) What adheres to the opening?
3) What nerve is here?
1) Right of median plan in central tendon
2) Inferior vena cava (IVC) adheres
3) Right phrenic nerve’s terminal branch.
What are the 3 openings in the diaphragm? List their locations.
1) Caval opening (in central tendon)
2) Esophageal hiatus (right crus forming sphincter)
3) Aortic hiatus (posterior to diaphragm)
1) What 3 things go through the esophageal hiatus?
2) Where is it?
1) Vagus nerve trunks, esophageal vessels, & lymphatics
2) In right crus (forming sphincter) at about T10 level
What two things go through the aortic hiatus posterior to diaphragm?
Azygos vein & thoracic duct
Where does gas exchange occur?
The last 3 parts of the trachea:
1) Bronchioles
2) Alveolar ducts
3) Alveolar sacs
__________ is slightly on left side of vertebral bodies, __________ is on the right side.
Aorta; SVC
There’s a gap in the diaphragm for what muscle?
Psoas
1) What is just inferior to the aortic hiatus?
2) What’s just inferior to that?
1) Celiac trunk
2) Superior mesenteric artery
1) What muscle does the phrenic nerve cross over?
2) Where does it go after the diaphragm?
1) Anterior scalene m.
2) Enters thorax anterior to subclavian artery and posterior to subclavian vein
Why do we care about the phrenic innervation of the diaphragm?
Right phrenic nerve may be responsible for paralysis of right hemidiaphragm
*might be on quiz
What is within the central mediastinal cavity?
Pericardium, pericardial cavity, heart & great vessels, trachea, esophagus
What two things are within the right & left pulmonary cavities?
Lungs and the pleural cavities
1) What is the central compartment of the thoracic cavity?
2) What pleura are found here?
3) What thoracic viscera does this compartment contain?
1) Mediastinum
2) Mediastinal pleura
3) All the viscera in thorax except lungs
What are the inferior and superior borders of the mediastinum called? What makes up the inferior part?
1) Superior thoracic aperture
2) Inferior thoracic aperture: diaphragm
1) Where are the anterior and posterior boundaries of the superior mediastinum?
2) Where is the transverse thoracic plane?
1) Superior thoracic aperture (first rib, clavicle, & jugular notch) to sternal angle anteriorly; to T5 posteriorly.
2) Runs anterior-posterior horizontally, from sternal angle anteriorly to superior endplate of T5 posteriorly
1) What are the boundaries of the inferior mediastinum?
2) What further divides the inferior mediastinum?
1) Transverse thoracic plane anteriorly, to diaphragm
2) Pericardium
What are the 3 divisions of the inferior mediastinum, and what do they contain?
1) Anterior mediastinum: clear space
2) Middle mediastinum: heart
3) Posterior mediastinum: esophagus and descending thoracic aorta
Describe the esophageal plexus of nerves:
1) What is it made up of?
2) What does it modulate?
1) Made up of postsynaptic sympathetic and presynaptic parasympathetic fibers
2) Gives branches to the esophagus to modulate the enteric nervous system (smooth muscles of GI viscera)
What does the cardiopulmonary plexus supply?
Where does it go?
1) To the heart itself and smooth muscles of airways
2) Follow vessels through the hilum as part of the root of the lung
What does the vagus nerve do once it gives off the left and right recurrent laryngeal nerves? (3 things)
1) Forms net around trachea as a part of pulmonary plexus and around esophagus as part of esophageal plexus
2) Then anterior and posterior vagus nerves form vagal trunk at the esophageal hiatus (along with sympathetic fibers)
3) Goes into esophagus, bronchial smooth tissue, and cardiac muscle
What are the two layers of the serous (inner) layer of the pericardial sac, and what are they attached to?
What is between them?
1) Outer parietal layer: adhered to the fibrous layer
2) Inner visceral layer: adhered to the heart, aka epicardium
Pericardial cavity is between them
1) What is the pericardial cavity?
2) What is the transverse pericardial sinus?
3) What is the other pericardial sinus?
1) Potential space with thin film of serous fluid
2) Reflection of pericardium
3) Oblique pericardial sinus
What structure of the heart is similar to the pleura of the lungs?
The pericardium
What does the pericardium fuse with?
Tunic adventitia
How does blood enter and exit the right side of the heart?
Enters: SVC and IVC
Exits: Pulmonary artery
How does blood enter and exit the left side of the heart?
Enter: Pulmonary veins
Exit: Aorta
What are the 3 layers of the pericardium?
1) Fibrous (gray)
2) Parietal serous
3) Visceral serous (aka epicardium)
What are the major branches of thoracic aorta?
1) Coronary arteries
2) Right brachiocephalic trunk
3) Arch of aorta
4) Posterior intercostals
What are two branches of the right brachiocephalic trunk?
1) Right common carotid
2) Right subclavian
What two things come off the arch of the aorta?
1) Left common carotid
2) Left subclavian
What is inside the aortic SL valve?
Lateral sinuses contain the right and left coronary arteries
Describe the anatomy of the left and right coronary arteries
1) Left coronary artery is usually the main/ dominant one, has 2 branches: left anterior descending/ anterior IV septal branch (descends along anterior margin of AV septum) and the circumflex branch.
2) Right coronary artery supplies blood to right ventricle, then goes behind and forms right septum and they meet on the posterior side of the apex.
Which recurrent laryngeal nerve has a longer course? Why is this important?
Left recurrent laryngeal nerve; more prone to injury
What provides autonomic innervation to the heart?
Cardiac plexus’s sympathetic and parasympathetic components
1) What forms the sympathetic part of cardiac plexus?
2) What do the fibers innervate?
1) Presynaptic cell bodies: thoracic lateral horn T1-5(6)
Postsynaptic cell bodies: cervical and superior thoracic paravertebral ganglia
2) SA + AV nodes and cardiac muscle cells
1) What forms the parasympathetic part of cardiac plexus?
2) Where are the postsynaptic cell bodies?
1) Presynaptic fibers of the CN10 (vagus).
2) Postsynaptic cell bodies (intrinsic ganglia) located near SA and AV node, along coronary arteries.
What does sympathetic stimulation do to the heart? What does it dilate?
Increases rate and force, dilates coronary arteries
The electrical cells of the heart pause everything to allow contraction of ________, then goes to bundle of his (anterior and posterior) and Purkinje fibers
atria
What are the two main divisions of the two coronary arteries?
1) RCA (right coronary artery) & posterior IV branch
2) LCA (left coronary artery), Anterior IV branch (LAD) & circumflex branch
What are two branches of the left coronary artery (LCA)?
Anterior IV branch (LAD) & circumflex branch
1) What are the most important sinuses of the coronary arteries?
2) When during cardiac cycle are coronary arteries perfused?
1) Right and left aortic sinus
2) Diastole
Why is the left coronary artery involved in more arrythmias than right coronary artery?
Anterior 2/3 of the IV septum is perfused by the anterior IV septal branch of LCA; happens to be where the bundle of His branches run. If you have an occlusion here, you’re likely to affect the conduction system of the heart and see rhythms early on.
A complete occlusion of a left coronary artery is often called what?
“widowmaker’
Where do the coronary veins empty?
Into coronary sinus in posterior sulcus OR directly into cardiac chambers
The number one cause of death in Americans is?
CAD (coronary artery disease)
Atrial cardiac muscle cells propagate impulse as they do what?
contract
What does the bundle of His do? What do its branches supply?
Course down IV septum; dividing into right and left bundle branches to supply the papillary muscles and wall of ventricles.
How many leaves do the valves on the left side of the heart have?
1) Mitral valve (2 leaves)
2) Aortic valve (3 leaves)
List the path of blood through the heart including valves
R atrium
Tricuspid valve
R ventricle
Pulmonic valve
L atrium
Mitral valve (2 leaves)
L ventricle
Aortic valve (3 leaves)
What is the most common valvular heart disease that’s brought to clinical attention?
Aortic stenosis
What path does blood take in fetal circulation?
-Shunts blood from right side of heart to left or general circulation
-Blood flows through the ductus arteriosis to the left side
-Foramen ovale connects left and right atria
What 2 parts of fetal circulation becomes no longer patent or open shortly after birth?
Ductus arteriosus (becomes ligamentous arteriosus) and foramen ovale
What system is bypassed in fetal circulation?
Hepatic portal system
What 6 things do the LCA’s anterior IV br. (LAD) & circumflex br supply?
1) Left atrium
2) Most of left ventricle
3) Part of right ventricle
4) Anterior 2/3 IV septum
5) AV bundle conducting system
6) SA node 40%
