Part 2: Thorax Pleural Cavities

Pleural cavity is what

(There are 2 of them, housing a lung) is the thin fluid-filled space between the two pulmonary pleurae (visceral and parietal) of each lung. A pleura is a serous membrane which folds back onto itself to form a two-layered membranous pleural sac.

Chartistics of the trachea

- 16-20 C-shaped rings of hyaline cartilage - smooth muscle - ciliated pseudotratified cells - has goblet cells that secrets mucus

The parietal pleura can be subdivided into 4 regions

-Costal parietal -diaphragmatic parietal -mediastinal parietal -cervical (cupula)

Lungs are defined by fissures

-Right lung is heavier then the left lung -right lung has 3 lobes (defined by horizontal fissure) -left lung has 2 lobes (defined by oblique fissure) and a cardiac notch due to the heart

What are the structures inside the lung root for each lung

-bronchus -Pulmonary artery -pulmonary veins -lymphatic vessels -nerves

Pulmonary circulation with 3 different circuits *when in the lungs veins and arteries are backwards

1. Gas exchange (low pressure): -pulmonary arteries which carries deoxygenated blood -pulmonary veins carries oxygenated blood 2. Blood supply (nutrition) to pulmonary tissue: -bronchial arteries branch off the thoracic aorta and carries oxygenated blood to lungs -bronchial veins usually drain to the azygos system into the superior vena cava 3. Lymphatic drainage: - lungs have a rich freely connecting network of lymphatic vessels -the lymphatic vessels of the visceral pleura and lungs carry lymph to be filtered by lymph nodes located inside the lungs along the bronchial tree -lymph from the lungs drains to: 1. Pulmonary lymph nodes 2. Bronchopulmonary lymph nodes 3. Superior and inferior tracheobronchial lymph nodes

Lung surfaces are

Apex: superior part of the lungs Hilum: is located in the middle of the lungs that contains the inflow and outflow structures (aka root of the lungs) Mediastinal surface: in contents with mediastinal pleura Costal surface: lung surfaces in contact with thoracic wall Diaphragmatic surface: inferior surface of the lungs; in contact with diaphragm

The costal parietal:

Attached to inner side of ribs both anterior and posteriorly

Which structure below leaves the most pronounced impression on the right lung

Azygos vein

Diaphragmatic (parietal) pleura:

Covers diaphragm

Mediastinal (parietal) pleura:

Covers lateral sides of mediastinum and at hilum of lung forms a pleura sleeve and a pulmonary ligament (not a real ligament)

Cervical (parietal) pleura:

Covers the lungs apexes

Parietal pleural is continuous with the visceral layer of the pleura at the _____________ of the lungs

Hilum

The lung root structures are located at _________ and are surrounded by a pleural sleeve

Hilum

The lungs are surrounded by visceral pleura, the visceral pleura is attached to the mediastinal structures by the ___________

Hilum

The right and left bronchi enters the lungs through the ___________ (hint lung root)

Hilum

What's special about the pleural recesses

Is a safe point to access the pleural cavities without injuring the lungs

Lymph from the parietal pleural drains into __________nodes in the thoracic wall and cavity before entering the bronchomediastinal trunk

Lymph

What is pleural reflections

Occurs when a fold is made so that the pleura can change direction can start going the other direction -for example: costal to diaphragm pleura or costal to mediastinal pleura)

What is a pleural recesses:

Regions where two areas of the parietal pleura are in contact -for example: costodiaphragmatic recesses (right and left) or costomedtastinal recesses (right and left)

The pleural cavities contain serous fluid to lubricant the surfaces and prevent friction during

Respratioy movements

Details about the lungs:

Right lung: -one main bronchi (shorter and wider) -3 lobar bronchi (upper , middle, lower) -10 bronchopulmonary segments - Left lung: -one main bronchi (longer) -2 lobar bronchi (upper, lower) -8 bronchopulmonary segments

Where do the azygos vein drain

Superior vena cava

Where does the trachea bifurcates

T4/5 located at the sternal angle

Much of the lymph thorax drains in left and right ____________________ lymphatic trunk (hint BMTs)

bronchomediastinal lymphatic trunks (BMTs)

When you see bronchial THINK OF:

bronchomediastinal trunk

The visceral pleura lines the.....

is the delicate serous membrane that covers the surface of each lung (the lung parenchyma) and dips into the fissures between the lobes. The parietal pleura is the outer membrane which is attached to the inner surface of the thoracic cavity. It also separates the pleural cavity from the mediastinum.

The parietal pleura lines the...

is the outer membrane which is attached to the inner surface of the thoracic cavity. It also separates the pleural cavity from the mediastinum. The parietal pleura is innervated by the intercostal nerves and the phrenic nerve. Between the membranes is a fluid filled space called the pleural cavity.