PLEURISY, an inflammatory disease of the pleura (q.v.). It is either dry or accom panied by effusion. Dry or fibrinous pleurisy is characterized by an inflamed area, usually of small extent, covered with a layer of plastic lymph and somewhat roughened. Its invasion is accompanied with sharp pain and a dry cough, and friction-sounds are heard on placing the ear to the chest. Adjacent portions of the membrane may adhere together, forming ad hesions which become permanent and limit the of the lung. Pleurisy is usually due to cold, unless secondary to another disease, such as penumonia, tuberculosis or cancer. Fre quently an arrest of the inflammatory process occurs, and the fibrinous layer disappears from the surface of the pleura by absorption. not, there may be an effusion of serum into the space between •the two layers of the pleura. The amount of effusion may be so great as to cause serious displacement of the lung or heart. If small in amount the fluid is often reabsorbed; but otherwise it must be removed by tapping. The fluid at first is pale and yellowish, or stained with blood-pigment. Later it becomes turbid, and if it becomes infected by bacteria carried into the pleura by the lympathics, or entering through a penetrating wound or during the progress of malignant disease or tubercle, it is converted into purulent matter. The con dition is then termed empyema, or chronic puru lent pleurisy, and is grave. The pus may pene trate the wall of the pleural cavity and the lung-tissue and burst into a bronchial tube and be coughed up. Or it may perforate the dia phragm, enter the peritoneal cavity and cause a purulent peritonitis. Few cases recover with out surgical treatment which consists of open ing the suppurating cavity and providing drainage.
In all pleurisy breathing is apt to be shallow and difficult, and general weakness, loss of appe tite, headache and rapid pulse are noted. When pus appears in a pleural cavity there is an ir regular temperature, a succession of chills and recurrent sweats. Upon the entrance of fluid into the pleura the friction-sounds disappear, and a dullness and later a flatness is ascertained by percussion over the position of the effusion.
Wet or sero-fibrinous pleurisy may continue for months, and the compressed lung may never ex pand again to its former volume, but may be. come Tuberculous pleurisy occurs as a result of tuberculosis of the lung, in a vast number of cases, as a primary disease. As a secondary implication, dry pleurisy always oc curs when the tubercular process reaches the surface of the lung. Hemorrhagic pleurisy, or with a bloody effusion, occurs fre quently in cases of cancer, Bright's disease and certain fevers, as well as in tuberculosis.
According to the situation of the lesion, pleurisy is termed diaphragmatic or interlobu lar. When limited by adhesions which form pockets, it is termed encysted. In the treatment of pleurisy little medicine is used. A cathartic is desirable at the outset. Adhesive-plaster straps are employed, fastened around the chest, or half of it, to secure immobilisation of the affected side. An ice-bag gives relief from pain and limits the inflammation. Counter irritation may be secured with iodine or mustard, but blis ters and cups are now seldom employed. Vapor baths, to cause diaphoresis, and diuretics are rarely required. Salicylates are useful in some cases. Aspiration of the fluid is secured by means of a hollow needle to which a suction pump is attached, a method invented and intro duced by Wyman of Cambridge and Bowditch of Boston. The needle is inserted generally in the axillary line and the operation is practically without risk. The fluid is withdrawn slowly, and even as much as a quart may he removed with safety. Often after a small fraction of an effusion is removed the remainder will be ab sorbed spontaneously. In cases of empyema a free incision is usually made and open drain age secured. Sometimes it is necessary to re set a part of one or two ribs. After recovery from empyema the chest is usually sunken and flattened.
a perennial herb of the genus Asclepias (q.v.).