chapter 25

visceral pleura has sufficient blood supply via bronchial arteries, which are direct branches of the

descending thoracic aorta

the pleura lining the internal surface of the thoracic wall, diaphragm and mediastinum

parietal pleura

The mediastinum is further subdivided into 4 mediastina:

1. anterior mediastinum 2. superior mediastinum 3. middle mediastinum 4. posterior mediastinum

If for any reason the negative pressure of the pleural cavity is lost from a chest wound, what would happen to the lung?

It would collapse because of its inherent elasticity (internal elastic fibers would shorten

the pleural cavity is maintained in a state of continuous ______ to keep the visceral pleura and parietal pleura to the thoracic wall and diaphragm. Thus any movement in the thoracic wall and diaphragm is reflected in a corresponding movement of the lung. This is the basis of breathing

negative pressure

a _______ is a double layered membrane composed of an inner mesothelium and outer connective tissue layer. The pleura is subdivided according to location into ____ and _______

serous membrane parietal and visceral pleura

the parietal pleura is subdivided into 4 parts:

1. Costal parietal pleura 2. Cupolar (cervical) parietal pleura 3. Diaphragmatic parietal pleura 4. Mediastinal parietal pleura

portion of the parietal pleura that forms the lateral boundaries of the mediastinum. It lines the outer and lateral surfaces of the pericardium

Mediastinal parietal pleura

caval opening for the inferior vena cava

TV 8

Diaphragm openings include:

TV 8 TV 10 TV 12

T/F: parietal pleura is insensitive to pain, containing few nerve fibers

false- it is sensitive to pain and has a rich nerve supply

covers the surface of the lung except at the hilus (the location where all structures that enter or leave the lung pass)

visceral pleura

contents of the middle mediastinum

1. heart 2. great vessels (SVC, aorta, pulmonary trunk) 3. pericardium 4. phrenic nerve

contents of posterior mediastinum

1. thoracic aorta 2. esophagus 3. thoracic duct 4. azygous vein 5. vegas nerve 6. sympathetic trunk

contents of superior mediastinum

1. thymus 2. great vessels (aorta, superior vena cava, pulmonary trunk) 3. brachiocephalic veins 4. trachea 5. esophagus (25 cm long, conduit for food from the pharynx to the stomach) 6. thoracic duct 7. vagus nerve and recurrent laryngeal nerve 8. phrenic nerve 9. azygos vein (drains blood from the posterior thoracic wall; drains into the superior vena cava)

portion of the parietal pleura covering the upper surface of the diaphragm

Diaphragmatic parietal pleura

contents of anterior mediastinum

loose connective tissue thymus

Diaphragm O: I: A: I:

Origin: 1. periphery posterior to the xiphoid process 2. lower 6 ribs 3. posterior abdominal wall Insertion: central tendon Action: inspiration Innervation: phrenic nerve

esophageal hiatus for the esophagus and CN X, Vegas nerve

TV 10

aortic hiatus for the aorta

TV 12

collapse of a lung is called ______, and the presence of air in the pleural cavity. is called ________

atelectasis pneumothorax

portion of the parietal pleura that lines the sternum, ribs, and intercostal muscles

costal parietal pluera

reflection of the parietal pleura at the junction of costal pleura and diaphragmatic pleura; the inferior border of the lung fills this recess during strenuous breathing

costodiaphragmatic recess (B)

reflection of the parietal pleura at the junction of the costal pleura and mediastinal pleura; the anterior border of the lung fills this recess during strenuous breathing

costomediastinal recess (A)

portion of the parietal pleura that courses over the apex of the lungs; it reaches as high as the neck of the first rib

cupolar (cervical) parietal pleura

The visceral pleura dips into _______ that separate the lobes of the lungs and is

fissures

the diaphragm forms the ______ boundary of the thorax

inferior

the only thoracic structure not within the mediastinum is the

lungs

a space between the right pleura and the left pleura of the thorax

mediastinum or interpleural space

a thin serous membrane located within the thoracic cavity on both the right and left side

pleura

space between parietal and visceral pleura. This area is of capillary thickness and is filled with a thin film of fluid

pleural cavity

like the visceral pleura, the parietal pleura also has a rich blood supply derived from:

posterior intercostal arteries internal thoracic arteryes (internal mammary arteries)

azygos vein drains blood from the ________ and into the _______

posterior thoracic wall superior vena cava

areas where two parts of the parietal pleura join (areas not occupied by lung) are referred to as _____; 2 exist including:

recesses 1. costomediastinal recess 2. costodeaphragmatic recess

the mediastinum extends from the _______ anteriorly to the ______ posteriorly and from the ______ superiorly to the ______ inferiorly

sternum vertebral column thoracic inlet diaphragm

the interpleural space contains all organs of the thorax except:

the lungs

the mediastinum can now be accurately defined as the space between:

the right and left mediastinal pleura

T/F: visceral pleura is insensitive to pain, containing few nerve fibers

true