Organization of Thoracic Viscera Flashcards
What passes through the superior thoracic aperture?
Trachea, esophagus, as well as many vessels and nerves
What are the boundaries of the superior thoracic aperture?
First thoracic vertebra
First pair of ribs and costal cartilages
Superior margin of the manubrium sterni
What are the boundaries of the inferior thoracic aperture?
12th thoracic vertebrae
Costal margin
Xiphosternal joint
What is the suprapleural membrane?
Thickening of endothoracic fascia above superior thoracic aperture that prevents bulging of lungs into neck
Where are the parietal and visceral pleura of the lungs continuous with each other in the thoracic cavity?
They are continuous with each other around the root of the lung
What are the 4 divisions of the parietal pleura based on the location?
- Costal pleura - lines thoracic wall
- Cervical pleura (cupola) - extends through thoracic inlet into the neck
- Diaphragmatic pleura - covers the diaphragm
- Mediastinal pleura - covers the mediastinal surface of each pleural sac
What is the pulmonary ligament?
The reflection of the mediastinal parietal pleura at root of lung where it sags below the hilus of the lung; creates a double layer of pleura.
What limits the pleural cavities? What are contained within the pleural cavities?
Pleural cavities are limited by the pleural reflections between mediastinal pleura and diaphragmatic pleura
The lungs are contained in the pleural cavity.
What does the right and left pleura deviate out laterally?
At the xiphosternal joint (7th rib)
At what level of costal cartilage does the left pleura deviate to create the shallow notch called the bare area?
At level of 4th costal cartilage. The bare area is important for pericardiocentesis
What are the lower borders of the pleural reflections for both right and left?
The pleural reflection crosses the 8th rib at the midclavicular line
Crosses the 10th rib at the mid axillary line
Crosses the 12th rib adjacent to the vertebral border on the posterior surface
What are the lower borders of the lungs with respect to the ribs?
The lungs cross the 6th rib at the midclavicular line
cross the 8th rib at the mid-axillary line
Crosses 10th rib adjacent to vertebral border posteriorly
What is a pleural recess?
The portions of parietal pleura where the lungs do not reach into, so the parietal pleura are touching, as the lungs do not fill the pleural cavity.
What are the 2 major pleural recesses, and what two pleura form them?
Costodiaphragmatic recess: at the reflection of costal pleura onto diaphragmatic pleura
Costamediastinal recess: At the anterior reflections of costal pleura onto mediastinal pleura
Which recess does the lingula enter during maximal inspiration?
Left costomediastinal recess (larger on left rather than right because of the cardiac notch)
At which thoracic vertebra is the superior and inferior mediastinum separated?
4th thoracic vertebra
What limits the superior mediastinum superiorly? What limits the inferior mediastinum inferiorly?
Superior mediastinum is limited superiorly by the superior thoracic aperture
Inferior mediastinum is limited inferiorly by the diaphragm
What portions is the inferior mediastinum separated into?
The anterior mediastinum, the middle mediastinum, and the posterior mediastinum
Which mediastinum contains the pericardial sac and its contents?
The middle mediastinum