Thorax Flashcards
Where do intercostal veins drain into?
The azygous and internal thoracic veins
What do the intercostal arteries branch into?
The thoracic aorta and internal thoracic arteries
What are the intercostal nerves?
The anterior and ventral rami of the thoracic spinal nerves
What innervates the diaphragm?
Phrenic nerve
What does the phrenic nerve come off of?
Ventral Rami of C3, C4, C5
What are the three main opening of the diaphragm?
The aortic hiatus, the esophageal hiatus, and the caval opening
What spinal lev does the aortic hiatus occur?
T12
Where is the aortic hiatus?
It is through the right and left crura of the diaphragm and marks the termination of the thoracic aorta/ beginning of the abdominal aorta, the thoracic duct and often the azygos vein.
What is the esophageal hiatus?
It is within the muscular part of the diaphragm and transmits the esophagus and vagus nerves.
What is the caval opening?
Located within the central tendon of the diaphragm and contains the inferior vena cava and sometimes the right phrenic nerve.
What is the mediastinum?
The space that is sandwiched between the two pleural sacs and refers to all structures that lie between the lungs, extending from superior thoracic aperture to the diaphragm
How is the mediastinum divided?
By a line drawn horizontally from the sternal angle to the lower border of T4 into the superior and inferior mediastinum.
What is the inferior mediastinum subdivided into?
The anterior, middle, and posterior mediastinum
What is the anterior mediastinum
It contains connective tissue, fat, and remnants of the thymus gland
What does the middle mediastinum contain?
The heart and roots of the great vessels (superior vena cava, aorta, pulmonary trunk, pulmonary veins) enclosed in the pericardial sac as well as the phrenic nerves.
What does the posterior mediastinum contain?
Descending aorta, azygous vein, thoracic duct, esophagus, trachea, and vagus nerves
What is the lung encased in?
A pleural sac formed by a continuous serous membrane called the pleura.
Where is the only point of attachment of the right and left lung?
At the root or hilum of the lung
What is the part of serous membrane that covers the lung called?
The visceral pleura.
What is the portion of the serous membrane that lines the thoracic cavity?
The parietal pleura.
What is the space between the visceral and parietal pleura called
The pleural cavity
What is pneumothorax
An accumulation of air in the pleural cavity, the lung collapses.
What is costodiaphragmatic recess?
Pleural recesses formed by the reflection of the costal and diaphragmatic pleura.
What is costomediastinal recesses?
Where the costal and mediastinal pleural meet.
What is pleural effusion?
Abnormal accumulation of fluid in the pleural space.
What is thoracentesis?
A procedure in which a needle in used to enter the pleural cavity and aspirate accumulated fluid.
Where is thorancentesis performed?
1-2 intercostal spaces below level of effusion, no lower than the 8th intercostal space.
What innervates the costal parietal pleura?
Intercostal nerves
What innervates both the mediastinal parietal pleura and diaphragmatic parietal pleura?
phrenic nerves.
What is visceral pleura innervated by?
Autonomic nerves
what is the pericardium?
Fibro-serous sac that encloses the heart and roots of the great vessels. It resides within the middle mediastinum.
What is the pericardial sac composed of?
Strong dense, fibrous layer (fibrous pericardium).
What does the serous pericardium consist of?
A parietal layer (parietal pericardium) that lines the inner surface of the fibrous pericardium and a visceral layer (visceral pericardium) that forms the outer layer of the hear (epicardium) and roots of the great vessels.
What is the pericardial cavity?
A potential space between the visceral pericardium and parietal pericardium.
Where is the transverse pericardial sinus?
Posterior to the ascending aorta and pulmonary trunk and anterior to the superior vena cava.
Where is the oblique sinus?
It is located behind the heart, surrounded by a reflection of serous pericardium around the right and left pulmonary veins.
How many chambers does the heart have
Four chambers- 2 atria and 2 ventricles.
Where are the atrioventricular valves located?
Between atria and ventricles.
Where are the semilunar valves?
Between the ventricles and great arteries.
Where is deoxygenated blood returned to the heart through?
The interior and superior vena cava into the right atrium and the right atrioventricular valve (tricuspid)
From the right atrium, where does the blood move?
To the right ventricle and is then ejected through the pulmonary semilunar valve into the pulmonary trunk, where it then travels to the lungs to become oxygenated.
How does oxygenated blood return from the lungs to the heart?
Through pulmonary veins, draining into the left atrium.
How does blood pass through the left atrium to the left ventricle.
The mitral or bicuspid
What do cardiac valves do?
They prevent backflow of blood
What are the two groups of the cardiac valves?
The semilunar valves and atrioventricular valves
How many cusps do the aortic and pulmonary valves have? What are they
3: the left, right, and anterior (pulmonary valve) or posterior (aortic valve)
Where are the openings for the left and right coronary arteries?
Adjacent to the left and right cusps.
What are the atrioventricular valves?
The mitral or bicuspid (2 cusps) on the left, the tricuspid on the right.