Heart And Lungs

Front 1

1) what constitutes the tracheobronchial tree?
2) where's the trachea located and where does it bifurcate?

Back 1

1) The sublaryngeal airway constitutes the tracheobronchial tree.
2) The trachea, located within the superior mediastinum, constitutes the trunk of the tree.
• The trachea bifurcates at the level of the transverse thoracic plane into main (primary) bronchi, one to each lung, passing inferolaterally to enter each lung at its hilum.

Front 2

what's the difference between the right main bronchus + the left main bronchus?

Back 2

The right main bronchus is wider, shorter, and runs more vertically than the left main bronchus as it passes directly to the hilum of the lung.
• The left main bronchus passes inferolaterally, inferior to the arch of the aorta and anterior to the esophagus and thoracic aorta, to reach the hilum of the lung.

Front 3

where can we find a carina?

Back 3

The last tracheal ring features the carina, a midline cartilaginous ridge that separates the lumens of the primary bronchi

Front 4

Right vs. Left Lung

Back 4

Right Lung:
• •
Three lobes: – Superior – Inferior – middle
Two fissures: – obliqueand
horizontal
Left Lung:
• Two lobes: – superior
– inferior • One fissure:
– oblique

Front 5

where is the hilum of the lung, and what does it contain?

Back 5

Centered on the mediastinal surface of each lung
Contains: • Primary bronchus • Pulmonary artery • Pulmonary veins • Bronchial arteries

Front 6

Describe the pleural sac?

Back 6

Pleural sac is made up of two layers of pleura
– Visceral pleura - invests the lungs (including within the fissures)
– Parietal pleura - lines the thoracic wall
• Parts of the parietal pleura are named for where they adhere:
• EX: costal, mediastinal, diaphragmatic

Front 7

1) What is the pleural cavity and what does it contain?
2) What does the cervical pleura + apices of lung lie posterior to?

Back 7

Pleural cavities
– Potential space between the two layers of pleura
– Contains pleural fluid to allow parietal and visceral pleura to slide smoothly against each other during respiration.
2) runs posterior to subclavian arteries

Front 8

Describe pulmonary circulation

Back 8

The pulmonary trunk from the right ventricle of the heart divides into right and left pulmonary arteries, which transport poorly oxygenated blood to the lungs.


•The pulmonary arteries subdivide into lobar and segmental arteries within the lungs.
•After passing through the pulmonary capillaries where gas exchange occurs, the blood drains into the pulmonary veins, which return the well-oxygenated blood to the left atrium of the heart

Front 9

What do the bronchial arteries and veins supply?

Back 9

1) The bronchial arteries supply blood for the nutrition of the supporting tissues of the lungs and visceral pleura. These arteries typically arise from the thoracic aorta.

2) The bronchial veins drain some of the blood supplied to the lungs by the bronchial arteries; the rest is drained by the pulmonary veins.

Front 10

Describe the innervation of the pleura

Back 10

Pleura Visceral – none.
Parietal - Intercostal and Phrenic nerves.

Front 11

Describe the innervation of the lung

Back 11

Lung:
Sympathetic from sympathetic chain
Effects: bronchodialation, vasoconstriction
Parasympathetic from vagus nerves
Effects: bronchoconstriction, vasodialation

Front 12

What are the 2 layers of the pericardium?

Back 12

– Outer: Fibrous – Inner: Serous

Front 13

What's cardiac tamponade?

Back 13

compression of the heart due to fluid accumulation within the pericardium

Front 14

Describe features of the right atrium.

Back 14

• Pectinate Muscles
•Wall of atrium

• Crista Terminalis
•Between smooth and muscular portions

• Opening of Coronary
Sinus
•coronary venous system

• Fossa Ovalis
•Remnant of foramen ovale


• Right Auricle
•Can increase capacity of atrium

Front 15

Describe features of the right ventricle

Back 15

• Chordae Tendinae
•Stabailize valve cusps

• Papillary Muscles
•Contract to tighten chordae tendinae

• Trabeculae Carnae
•Muscular ridges

• Moderator Band
•Part of conduction system

• Tricuspid Valve
• Pulmonary Valve

Front 16

Describe the function of the following
1) SA node
2) AV node
3) right and left bundles
4) moderator band

Back 16

•The SA node initiates an impulse that is rapidly conducted to cardiac muscle fibers in the atria, causing them to contract.
•The impulse spreads by myogenic conduction that rapidly transmits the impulse from the SA node to the AV node (though AV node also receives some innervation).
•The signal is distributed from the AV node through the AV bundle and its branches, the right and left bundles, which pass on each side of the IV septum to supply the papillary muscles and the walls of the ventricles.
•Branches of the right bundle stimulate the anterior papillary muscle through the moderator band

Front 17

What is the heart innervated by?

Back 17

The heart is supplied by autonomic nerve fibers from the cardiac plexuses. These networks lie anterior to the bifurcation of the trachea, posterior to the ascending aorta, and superior to the bifurcation of the pulmonary trunk.

Front 18

Describe the sympathetic supply to the heart?

Back 18

Sympathetic supply:
– presynaptic fibers with cell bodies in the lateral horn of the superior 5-6 thoracic segments of the spinal cord
– postsynaptic sympathetic fibers with cell bodies in the cervical and superior thoracic paravertebral ganglia of the sympathetic trunks. The postsynaptic fibers end in the SA and AV nodes
– Sympathetic stimulation increases the rate and the force of heart contraction. Sympathetic stimulation (indirectly) produces dilation of the coronary arteries by inhibiting their constriction. This supplies more oxygen and nutrients to the myocardium during periods of increased activity.

Front 19

Describe the parasympathetic supply to the heart

Back 19

– –
–
presynaptic fibers of the vagus nerves
postsynaptic parasympathetic fibers also end in the SA and AV nodes and directly on the coronary arteries.
Stimulation of parasympathetic nerves slows the heart rate, reduces the force of the heartbeat, and constricts the coronary arteries, saving energy between periods of increased demand.

Front 20

Where is the ascending aorta located? What are the only branches of the ascending aorta?

Back 20

Middle mediastinum also have the ascending aorta (intrapericardial).

Only branches are the coronary arteries

Front 21

Describe the divisions of the aorta

Back 21

Aorta > Right coronary A > SA node > R. Marginal A > Posterior Interventricular A

Aorta > Left Coronary A > Anterior Interventricular > Circumflex A

Front 22

In relation to the coronary arteries, where do the great, middle, small, and anterior cardiac veins run ?

Back 22

Coronary Sinus
• Great Cardiac Vein w/ anterior
interventricular a.
•Middle Cardiac Vein w/ posterior
interventricular a.
• Small Cardiac Vein w/ right marginal a.
Anterior Cardiac Vein - to right atrium

Front 23

Where does the superior and inferior mediastinum extend, and what do they include?

Back 23

The superior mediastinum extends inferiorly from the superior thoracic aperture to the horizontal plane which includes the sternal angle anteriorly and passes approximately through the junction (IV disc) of T4 and T5 vertebrae posteriorly

thymus, 'great vessels', vagus and phrenic nerves, trachea, esophagus, + thoracic duct

• The inferior mediastinum between this plane and the diaphragm is further subdivided by the pericardium into the anterior, middle, and posterior parts. The middle mediastinum contains the heart and great vessels.

Front 24

What supplies the thymus?

Back 24

A rich arterial supply to the thymus is derived mainly from the anterior intercostal and the anterior mediastinal branches of the internal thoracic arteries. **
• The veins of the thymus end in the left brachiocephalic, internal thoracic, and inferior thyroid veins.

Front 25

Where does the arch of the aorta begin and where does it ascend and descend?

Back 25

– begins posterior to the 2nd right sternocostal joint
– Ascends anterior to the right pulmonary artery and the bifurcation of the trachea
– Descends posterior to the root of the lung and ends posterior to the 2nd left sternocostal joint, or T4

Front 26

Name the branches of the arch of the aorta

Back 26

– Brachiocephalic Trunk • Right Common
Carotid Artery *
• Right Subclavian Artery *
– Left Common Carotid Artery
– Left Subclavian Artery

Front 27

Where does the ligamentum arteriorsum pass?

Back 27

The ligamentum arteriosum
passes from the root of the left pulmonary artery to the inferior surface of the arch of the aorta

Front 28

Describe and 'venous great vessels'

Back 28

Left and Right Brachiocephalic veins (BCV)
– Each formed posterior to the sternoclavicular (SC) joint by union of internal jugular vein & subclavian vein

Superior Vena Cava
– Formed by the union of the left and right BCVs at the level of the inferior border of first right costal cartilage
– Lies on the right side of the superior mediastinum, anteriolateral to the trachea, and posterolateral to the ascending aorta
– Ends at the level of the 3rd costal cartilage
– Returns all blood from structures superior to the diaphragm, except the heart and lungs

Front 29

Where do the right and left vagus nerve cross?

Back 29

The right vagus nerve crosses anterior to the right subclavian artery and gives off the right recurrent laryngeal nerve, which passes medially to reach the trachea and esophagus.

The left vagus nerve passes anterior to the arch of the aorta, then gives off left recurrent laryngeal nerve which passes inferior and then posterior to the arch of the aorta and ascends between the trachea and esophagus to the larynx.

Front 30

How are the cardiac plexus, esophageal plexus, and vagus related?

Back 30

The vagus nerves continues and passes posterior to the root of the lung where it contributes fibers to the esophageal plexus. * The left and right vagus nerves also contribute to the pulmonary plexuses
* The right vagus also gives rise to the cardiac plexus

Front 31

What do the phrenic nerves supply?

Back 31

The phrenic nerves (C3,4,5) supply the diaphragm with motor and sensory fibers
• The phrenic nerves also supply sensory fibers to the pericardium and mediastinal pleura.
• Each nerve enters the superior mediastinum between the subclavian artery and the origin of the brachiocephalic vein
(The fact that the phrenic nerves pass anterior to the roots of the lungs provides an important means of distinguishing them from the vagus nerves, which pass posterior to the roots.)

Front 32

Where does the trachea descend? Where does the trachea end?

Back 32

The trachea descends anterior to the esophagus and enters the superior mediastinum, inclining a little to the right of the median plane

•The posterior surface of the trachea is flattened
•The trachea ends at the level of the sternal angle by dividing into the right and left main bronchi

Front 33

where does the esophagus begin + end?

Back 33

The esophagus is a fibromuscular tube that begins at the inferior border of the cricoid cartilage (C6) , passes through the esophageal hiatus of the diaphragm, and ends at the cardiac opening of the stomach opposite T11.
•It enters the superior mediastinum between the trachea and the vertebral column
•The esophageal nerve plexus (from R+L Vagus nerves) surrounds the esophagus

Front 34

1) where is the esophagus in relationship with the arch of the aorta?
2) in relationship with the atrium?
3) in relationship with thoracic duct?

Back 34

1) The esophagus is crossed on the left side by the arch of the aorta in the superior mediastinum
2) The esophagus passes immediately posterior to the left atrium of the heart (posterior mediastinum
3) Thethoracicductisposteriorto the esophagus and passes from right to left as it ascends (superior and posterior mediastinum)

Front 35

1) Where does the thoracic duct originate?
2) What does this convey to the venous system?
3) Where does is pass in relation to the esophagus?
4) Where does it drain into?

Back 35

1) Originates in chyle cistern in abdomen
2) most lymph of the body
3) The thoracic duct is posterior to the esophagus and passes from right to left as it ascends (at approx T6)
4) Drains into subclavian vein at junction of IJV

Front 36

1) Where does the anterior mediastinum lie?

2) what does it consist of?

Back 36

1) smallest subdivision of mediastinum, its between the body of the sternum + transversus thoracis muscles anteirorly and pericardium posteriorly
-continuous w/ superior mediastinum at sternal angle + limited inferiorly by diaphragm

2) loose CT; fat, lymphatic vessels; lymph nodes; branches of internal thoracic vessels

Front 37

1) where does the thoracic aorta begin and end?

Back 37

1) begins at lower edge of T4 + terminates anterior to inferior border of T12, where it endters through aortic hiatus.

Front 38

LIst the significant branches of the thoracic aorta?

Back 38

Significant branches:
– Esophageal arteries
– Bronchial arteries
– Superior phrenic arteries
– Posterior intercostal arteries – Small mediastinal arteries
– Pericardial branches

Front 39

In the posterior mediastinum, where is the thoracic aorta located in reference to the esophagus?

Back 39

1) on the left side of the esophagus

Front 40

Describe the azygos system of veins (including differences between R and L side)

Back 40

he azygos system of veins, on each side of the vertebral column, drains the back and thoracoabdominal walls as well as the mediastinal viscera.
• The major veins in the system are:
– azygos vein on the right- forms a collateral pathways between the SVC and IVC
– Arches over the root of the right lung to join the SCV
– hemiazygos vein and accessory hemiazygos vein on the left which usually drain to the azygos vein, though their path is quite variable

Front 41

What is the sympathetic trunk?

Back 41

1) 'chain' of ganglia that originates from lateral horns of thoracic + upper 3 lumbar spinal cord; sympathetic fibers travel to regional ganglia and then to target organs

Front 42

What are splanchnic nerves?

Back 42

The lower thoracic splanchnic nerves— also known as greater, lesser, and least splanchnic supply viscera inferior to the diaphragm.
• They consist of presynaptic fibers from the 5th through the 12th sympathetic ganglia
• Each perforates the ipsilateral crus of the diaphragm to enter the abdomen

Front 43

What mediastinal surface contains a groove for the esophagus?
Groove for the aortic?

Back 43

esophagus groove is on R lung (mediastinal surface)
aortic groove is on L lung (mediastinal surface)