Pleurae Flashcards
what is the pleurae
one covering each lung and serous membranes that line the lungs and thoracic cavity
what does the pleurae allow
They permit efficient and effortless respiration
what the two pleura
covers the lungs
covers the internal surface of the thoracic cavity.
where are the two parts of teh pleura continuous with each other?
hilum of each lung
what is the potential space between the viscera and parietal pleura, known as
the pleural cavity
describe the parietal pleural
The parietal pleura covers the internal surface of the thoracic cavity. It is thicker than the visceral pleura, and can be subdivided according to the part of the body that it is contact with:
desrbe the 4 pleuara
Mediastinal pleura – Covers the lateral aspect of the mediastinum (the central component of the thoracic cavity, containing a number of organ).
Cervical pleura – Lines the extension of the pleural cavity into the neck.
Costal pleura – Covers the inner aspect of the ribs, costal cartilages, and intercostal muscles.
Diaphragmatic pleura – Covers the thoracic (superior) surface of the diaphragm
describe the viseral pleura
The visceral pleura covers the outer surface of the lungs, and extends into the interlobar fissures. It is continuous with the parietal pleura at the hilum of each lung (this is where structures enter and leave the lung).
desribe the okeural cavity
The pleural cavity is a potential space between the parietal and visceral pleura. It contains a small volume of serous fluid, which has two major functions.
It lubricates the surfaces of the pleurae, allowing them to slide over each other. The serous fluid also produces a surface tension, pulling the parietal and visceral pleura together. This ensures that when the thorax expands, the lung also expands, filling with air.
what is a pneumothorax
if air enters the pleural cavity, this surface tension is lost
blood suplly to parietal pleua
The blood supply is derived from the intercostal arteries.
blood supply viseral pleura
Arterial supply is via the bronchial arteries (branches of the descending aorta), which also supply the parenchyma of the lungs.
nerve innervation parieta pleura
The parietal pleura is sensitive to pressure, pain, and temperature. It produces a well localised pain, and is innervated by the phrenic and intercostal nerves.
nerve innervation viseral pleura
The visceral pleura is not sensitive to pain, temperature or touch. Its sensory fibres only detect stretch. It also receives autonomic innervation from the pulmonary plexus (a network of nerves derived from the sympathetic trunk and vagus nerve).
what are the pleural recesses
Anteriorly and posteroinferiorly, the pleural cavity is not completely filled by the lungs. This gives rise to recesses – where the opposing surfaces of the parietal pleura touch.
