Careful observations with the thermometer give us important indications by which to diagnose the nature of the pleurisies. In those of a tubercular nature the temperature continues high, from 100° to 104° F., for weeks. When the effusion becomes purulent the temperature becomes like that of hectic fever—in the morning normal, and in the evening rising to 102°, or even 103½° or 104° F. Sometimes the temperature is one or two degrees higher on the diseased side than it is on the healthy side.
As in other inflammations, the pulse in this disease varies considerably. The researches of H. Newell Martin show that there is ordinarily a constant ratio between the pulse-rate and the temperature. If the temperature be high (over 102° F.), we must expect the pulse to be as frequent as 115 or even 120 per minute. In mild cases, where the temperature does not go beyond 99.5° or 100° F., the pulse will not exceed 90 to 96. In slight cases, where the fibrinous exudation is very limited, the pulse may not exceed 80. In tubercular and purulent pleurisies the pulse may vary between 100 and 120. When there is a relapse the pulse advances as the temperature rises. Anstie has called attention to the quality of the pulse, which follows a uniform course on the whole, regard being had to the general vital condition of the patient. In the first stage of acute pains, with more or less tendency to shivering, the pulse, as tested with the sphygmograph, presents the algid form—i.e. the pulse-waves are very small and nearly devoid of secondary markings. As soon, however, as flushing of the face occurs, and a general sense of burning heat of the skin, the pulse passes to the true pyrexial type; the waves become large and dicrotic. The sphygmograph uniformly shows that the large and somewhat bounding pulse is always less resistant than that of health.
Jaffé-Duval23 states that he found the temperature of the diseased side raised above that of the healthy chest. Subsequently, Peter,24 after a long series of researches, reported some very important results as to the localized parietal temperature in cases of pleuritic effusions: (1) He found that the parietal temperature, as tested by the thermometer, is always higher on the side of the pleurisy than that of the body as tested in the axilla; (2) that the elevation of the temperature increases as the effusion augments, the highest local temperature corresponding to the period of secretory activity of the inflamed pleura; (3) the rise affects both sides, but is greater over the diseased pleura; (4) the temperature falls by degrees as the effusion is reabsorbed—less on morbid side; (5) the absolute elevation of local temperature is greatest in the sixth intercostal space; (6) after paracentesis the parietal temperature is increased: this falls in a few hours where the effusion is not re-formed, but when such is the case it continues for some days. This local rise of temperature, he considers, is from hyperæmia and cell-production, caused by the traumatism from the needle added to the already-existing hyperæmia. This excessive congestion, caused by the accumulation of blood occurring when a large quantity of fluid is rapidly withdrawn, produces the syncope, pulmonary congestion, consecutive albuminous expectoration, the pain, and the oppression amounting sometimes to suffocation, and occasionally ending in death.
23 Thèse de Paris, 1875.
24 La France médicale, 4th May, 1878.
At the commencement in acute cases the respiratory acts become very frequent, even going to 40 or 50 per minute. They are short, interrupted, and superficial. Their frequency makes up for their incompleteness in furnishing sufficient air. The painfulness of each act forces the individual not to expand the walls of his chest more than he can avoid. Moreover, the high fever in itself produces frequent respiration. As the temperature falls the respiration becomes less abnormal. If the effusion forms rapidly, the patient may become oppressed, even when the quantity is not large. If it is thrown out gradually, the breathing is not so much interfered with until a large quantity forms, the organism becoming accustomed to the interference with the play of the lungs. The strength of the individual and the activity of his nutritive functions are materially lowered. Sometimes he breathes with difficulty, especially when he takes active exercise. The dyspnoea is very painful and alarming. The aëration of the blood is so materially interfered with that there results a large quantity of carbonic acid, which irritates excessively the respiratory nerve-centres.
During the acute stage the patient sometimes lies on his back, but more frequently on the well side, and exceptionally on the diseased side. He avoids lying on the side where the inflammation exists, because the weight of his body increases the pain. I have, however, seen patients who would persist in lying on the painful side and supporting it with their hand. It sometimes happens that a patient lies on the affected side, and will not move, because the movement gives him such acute pain. Ordinarily, he prefers to lie on the healthy side, even after the fluid has been poured out to a moderate degree, because his pain is less. When, however, the effusion has become great enough to deprive him of the use of the diseased side, he instinctively turns on that side, so as to avoid the weight of the fluid pressing upon the lung on the sound side. Moreover, he wishes to expand as much as possible the side whose respiratory force now needs to do double work. This change of position in patients has an unmistakable significance. It shows that the sufferer is aware that he is more comfortable lying on the diseased side. His physician's attention is drawn to the condition of the chest as influenced by the increased quantity of fluid pressing the air out of the lung.
Cough is not a constant symptom in pleurisy, but ordinarily it occurs at some stage of the disease. It is short, dry, and suppressed in character. It is painful, and therefore is avoided when possible, especially previous to the effusion. It disappears generally about the fourth or fifth day, when the effusion has attained a considerable amount. The cause of the cough has been generally supposed to be the exalted sensibility of the inflamed pleura, but Nothnägel maintains that such is not the case. Fraentzel holds that the cough is caused by the strain on the lung-tissue and the finer bronchi when there is a slight effusion. Cough brought on by change of position is one of the characteristic symptoms of large effusions into the pleura. If the lung is completely compressed by the pleuritic effusion, then no actual strain on the alveoli or the bronchi can exist. In such cases there is no cough, but it returns when the effusion decreases in quantity, and quite violently, if this occurs suddenly, as, for instance, in puncture of the chest (Fraentzel). In the latter case the cough is probably caused by the rush of blood and the sudden expansion of the chest.
Slight frothy expectoration may exist, but ordinarily there is none whatever, unless from bronchial catarrhal complications. In that case sero-mucous fluid is expectorated in small quantity. If it becomes viscid and tinged with blood, it is caused by pulmonic involvement.
In empyema, if the expectoration becomes purulent, we ought at once to suspect the presence of some circumscribed spots of necrosis of the pleuritic covering of the lung, which have allowed the pus from the pleural cavity to filter through the lung-tissue. By careful physical examination of the chest we can ascertain whether there has been any diminution in the quantity of fluid. When, as sometimes occurs, there is actual perforation of the lung, the pus from an empyema comes in quantity, through the bronchial tubes, out of the mouth. Patients may sink from exhaustion following this discharge, or if the discharge be excessive it may fill up the bronchial tubes too rapidly for its removal by expectoration, thus causing suffocation. This danger is increased if the discharge takes place during sleep.