Pleura

Location – either side of mediastinum within chest cavity

Layers of pleura – parietal @ visceral layer

Parietal layer- lines thoracic wall- covers thoracic surface of diaghram- extends root of neck to line the under surface of suprapleural membrane and extends

Visceral layer- completely covers the outer surfaces of lungs- extends

Pleural cuff- 2 layers continuous with one another by means of cuff of pleura- cuff surrounds structures entering and leaving lung at hilum of lung- pleural cuff hangs down as a loose fold

Parts of pleura- cervical pleura

Cervical pleura- extends up into neck- lines under surface of suprapleural membrane- reaches level 1 to 1.5 in. (2.5-4 cm) above medial third of clavicle

Costal pleura- lines inner surfaces of

Diagpragmatic pleura- covers thoracic surface of diaphragm

Mediastinal pleura- covers and forms lateral boundary of mediastinum- reflected as cuff around vessels abd bronchi at hilum of lung- continuous with visceral pleura- each lung lies free except at hilum- attached to blood vessels and bronchi that constitute the lung root- during full inspiration the lungs expand abd fill the pleural cavities- during quiet inspiration lung do not full occupy the pleural cavities at four sites

Pleural recesses(costodiaghraphmatic recess)- lower area of pleural cavity into which the lung expands on inspiration is referred to as

costodiaghragmatic surface- situated along the anterior margins of pleura= slit like pieces between costal and mediastinal parietal pleurae- separated by capillary layer of pleural fluid- during inspiration and expiration, anterior borders of lungs slide in and out of recesses

Nerve supply- parietal pleura is sensitive to pain, temperature, touch and pressure- cervical and costal – intercostal nerve- mediastinal – phrenic nerve- diaghragmtic – phrenic and lower six intercostal nerve

Mediastinum- median space of chest cavity extending from its inlet to outlet, bounded on each side by pleura and lung- above line is superior mediastinum- below line is inferior mediastinum- region ( superior and inferior)

Clinical antomy- pleural fluid- pleurisy

Pleural fluid(pleural effusion)- normally contains 5 to 10 ml of clear fluid- lubricates the opposing surfaces of visceral and paritela pleurae during respiration- formation of fluid results from hydrostatic and osmotic ppressure

Pleurisy- inflammation of pleural tissue secondary to inlfammtion of lung such as pneumonia- pleural surfacesbecomes coated with inflammatory exudatory, surfaces becomes rough- produce friction, pleural rub- can be heard such as stetoscho[e