The pressure is computed assuming an International standard sea-level pressure datum of 1013.25 hPa, and therefore is not necessarily the same as the aircraft's true altitude either above mean sea level or above ground level.he pressure is computed assuming an International standard sea-level pressure datum of 1013.25 hPa, and therefore is not necessarily the same as the aircraft's true altitude either above mean sea level or above ground level.
The term pleurisy (pleuritis) is inflammation or infection in the pleural space around the lungs. Pyothorax also known as empyema of the pleural cavity is the presence of pus in the pleural cavity between the layers of the pleural membrane Py/o-Pus.
The two lungs and their pleural sacs are situated in the thoracic cavity (figs. 22-1 and 22-2). The pleura is a thin, glistening, slippery serous membrane, inflammation of which is called pleurisy. The pleura lines the thoracic wall and diaphragm, where it is known as the parietal pleura.It is reflected onto the lung, where it is called the visceral pleura.The visceral pleura covers the lung and dips into its fissures.The facing surfaces of the parietal and visceral pleurae slide smoothly against each other during respiration.ir in the pleural cavity (pneumothorax) results in collapse of the lung. The pleura is supplied by adjacent arteries and nerves and has numerous lymphatics. Irritation of the parietal pleura causes pain referred to the thoraco-abdominal wall (intercostal nerves) or to the shoulder (phrenic nerve).