The common cause of pleurisy is exposure to cold. It may be caused by injury—a broken. rib, for example, pushed inwards and damaging the membrane. It is sometimes a complication of fevers—scarlet fever, typhoid fever, &c.—of kidney disease, of heart disease, and of blood poisoning ; and it is frequently tubercular. It may also be due to disease of the lungs them selves, that part of the pleura being involved that lies over the diseased area of lung. A small part only of the pleura may be affected in this way, and no pouring out of fluid occur, but the two folds of membrane become ad herent at the irritated part. This is called dry pleurisy.
Symptoms..—Usually the first thing of which a person affected with pleurisy complains is a pain or stitch in the side. The pain is of a stabbing or tearing character at a particular place, and does not move about. It is increased by deep breaths, generally becomes intense with coughing, sneezing, &c., and is increased also by moving the arm of that side. Loss of appetite, weakness, feverishness, furred tongue, quick full pulse, short shallow breathing, scanty and high-coloured urine are among the other symp toms. A short, dry cough is also common. The fever does not run very high, 102° or 103°. The conclusive signs are obtained by examining the chest. In the early stage, before fluid has been poured out, the friction sound referred to above may be heard. When effusion has taken place in any quantity, tapping the chest gives out a dull sound, and the breath sounds can no longer be heard (see p. 359). By tapping, the level of the fluid can be ascertained, the person sitting up, for as soon as one taps higher than the level of the fluid, a clear sound is produced. Another method, that even the most unpractised can ' make use of, is to apply one hand close to each side of the patient, the chest being quite bare, and then to ask the person to speak. The thrill of the voice ought to be communicated equally to each hand. If the pleura on one side is full of fluid, the thrill will be absent on that side. If the lung on one side has become solid, owing to inflammation or other cause, the pleura con taining no fluid, the solid lung will conduct the sound even more easily than the lung filled with air, so that while the thrill is felt on both sides, it will be very much increased on the diseased side. When fluid has been poured out, the pain usually begins to subside. In the early stage of the illness the person lies commonly on the sound side, pain preventing him turning on to the other. When much fluid has been poured out, however, he lies ou the affected side, for if lie were to lie on the sound side, the weight of the fluid on the top side would too much em barrass breathing. With effusion difficulty of breathing is greatly increased, and the person may even become livid, and breathes rapidly. Commencing recovery is indicated by dimin ished pain and feverishness. But the effusion remains long after the inflammation has passed, as is indicated by the breathlessness on sitting up, or on the slightest exertion. A physician
determines the progress towards complete re covery by tapping to discover whether a clearer sound is produced, and by listening to discover the return of the breath sounds.
In some cases the onset of the disease is not well marked, the patient suffering from languor and weakness, with stitch in the side, other symptoms being slight. Perhaps it slowly passes off, without the person being aware that he was affected with a serious disease; perhaps his symptoms increase till he is forced to lay himself up. In other cases the attack is sudden and severe, shivering fits, with high fever and severe stitch, indicating its occur rence.
Among the symptoms of formation of matter are shivering fits followed by sweatings.
Treatment.—The person should from the outset have perfect rest in bed, little talking being allowed, a good dose of opening medicine (epsom or seidlitz salts) being given early, and light nourishing diet being administered with out stimulants. Large hot linseed-meal poultices should be frequently applied to the affected side, to which mustard may be added now and again. A large flannel bandage round the chest should secure the poultices, and a dry one should be applied when the poultices are off. If the pain is severe grain of opium, or 12 drops of laudanum, may be given (to adults only) twice or thrice daily. That will, however, bind the bowels, which should be relieved by addi tional medicine, or by injections. When re covery has begun, moderate nourishing diet is to be given, and quinine and iron tonic, or iodide of iron (a tea-spoonful of the syrup four times daily). To aid the absorption of the fluid, occasional mustard poultices may be applied to the side, or fly-blisters may be used on one part of the side one day, and a day or two after on another part. Rubbing the side is useful if the condition of the skin permits. An occasional ' dose of medicine is a help.
It must be remembered that, even in favour able eases, the absorption of the fluid poured out takes some time—weeks, and even mouths. Further, freedom from breathlessness is no sign of absence of fluid, for there may be a consider able accumulation of fluid and little breathless ness. For months after the attack great cars must, therefore, be exercised.
Where the collection of fluid is very great, or where matter has formed, physicians now em ploy methods for the withdrawal of the fluid by inserting a fine tube into the pleural space through the chest wall, between two ribs, usually the 5th and (ith or Gth and 7th, about the line otthe arm-pit. It is done with precau tions to prevent the entrance of air and various impurities.
Pneumothorax is the term applied when there is au accumulation of air in the cavity of the pleura. The air may gain entrance from the outside by a wound, or from the lung by an opening produced by an abscess. It pro duces difficulty of breathing. If an opening communicates from the outside with the cavity,