Peripneumonia Pneumonia, Or Lung Fever, inflammation of the proper substance of the lungs. Pneumonia is one of the most frequent forms of inflammation, and is common to all ages. It prevails more frequently in spring and autumn than in summer and winter, in cold and temperate than in tropical climates. The prolonged exposure to cold is the cause to which it is most frequently attributed, but in many instances careful research cannot assign an exciting cause; it occurs oftenest among the ill fed, the intemperate, and those who suffer from crowding and want of ventilation; consecutive pneumonia, as it is then termed, frequently arises in the course of typhoid, typhus, and eruptive fevers. In many cases the patient is feverish and unwell for three or four days before the actual invasion of the disease; this is almost invariably marked by well defined rigor, followed by pain in the side, cough, accelerated breathing, and fever. The pain in the side, commonly felt beneath the nipple, is no guide to the seat of the disease; it is generally caused by accompanying inflammation of the pleura, is lancinating, and increased by inspiration and by motion of the thorax; according to Grisolle, it occurred in 272 out of 301 patients.

Accelerated breathing is an invariable symptom, the respirations varying from 30 to 50 in a minute, though they may be as frequent as 80. The pulse does not increase in the same ratio as the respiration; the ordinary relation of four pulsations to a single respiration is disturbed, and is reduced to three, two, or even less. Dr. Walshe says he has seen this perverted pulse ratio prove the first sign of pneumonia, appearing before crepitation or rusty expectoration. Cough is an almost invariable symptom, occurring commonly at the commencement of the disease; it is not paroxysmal, and is not aggravated at night. In a great majority of cases the cough is accompanied by expectoration, which is pathognomonic of the disease. It is tenacious, semi-transparent, little aerated, and of a lemon, orange, or rust color, according to the amount of blood with which it is combined. When free blood occurs in the expectoration, according to "Walshe, the pneumonia is complicated by the presence of tubercles. As the disease subsides, the expectoration gradually becomes opaque and bronchial. In some cases the expectoration is diffluent, watery, and of a dark color resembling prune or liquorice juice. This is always a serious symptom.

The pulse is most commonly frequent, full, and strong; the skin is hot; during the height of the disease the face is often deeply flushed, sometimes almost livid. The pathognomonic physical sign of the first stage of pneumonia is the crepitant rhonchus; this is fine, dry, equal, and heard chiefly at the end of the inspiration. To distinguish it fully it is often necessary to make the patient cough. In a short time the crepitant rhonchus is replaced by bronchial respiration; the breathing is loud, blowing, and tubular, and when the patient speaks the voice has the diffused resonance called bronchophony. At the limits of the bronchial respiration, while the inflammation is extending, the crepitant rhonchus is still heard. As bronchial respiration replaces fine crepitation, percussion becomes dull over the affected portion of the lung; at the same time the vibratory thrill felt by the hand placed upon the chest when the patient speaks becomes more marked. When pneumonia is central and the inflamed part of the organ is separated from the parietes by healthy lung tissue, both percussion and auscultation may give negative results.

When the attack of pneumonia results in recovery, as the general symptoms diminish in intensity and the expectoration becomes white or grayish, the bronchial respiration becomes less strongly marked, and over the parts last attacked a coarser and moister crepitation recurs; this is the redux crepitant rhonchus. With the return of the crepitant rhonchus the percussion note becomes clearer, until gradually the lung recovers its former condition. When on the other hand the attack is fatal, the general symptoms, with the exception of pain, persist, and are aggravated; the expectoration becomes of a dirty gray color, striated, and finally perhaps wholly purulent; the complexion grows pale, yellowish, and earthy looking; the skin is covered with a viscid sweat, and death is preceded by the tracheal rhonchus. In general the intelligence remains unimpaired to the last. In rare instances abscesses are formed in the lungs as a consequence of pneumonia. The duration of the disease is rarely less than 7 or more than 20 days. Very fatal in young infants and in old people, it is attended with but little danger between the ages of 6 and 50, when uncomplicated and occurring in patients of good constitution.

When pneumonia is double, when it is complicated with heart disease, with albuminuria, or with delirium tremens, when it occurs in constitutions deteriorated by fatigue, privations, or excess, its gravity is very greatly increased. It sometimes occurs as an epidemic, and is then severer than when it is sporadic. - In strong, healthy, young adults, a single full bleeding will often relieve the breathing, remove the pain, and diminish the force and frequency of the pulse; in other cases, where the pain in the side is severe, it is best to have recourse to cupping glasses. Afterward small doses of tartrate of antimony combined with morphia may be given every two or three hours. The patient should be kept in bed, the chest should be covered with an oiled silk jacket, and the diet should be bland but nutritious. Where patients are feeble, broken down, or advanced in years, general bloodletting is inadmissible, and even antimony must be used with great caution. A nutritious diet, and the administration of carbonate of ammonia, and frequently of stimulants, form in such cases the appropriate treatment. - Chronic pneumonia, except as an attendant upon tubercle or cancer, is exceedingly rare. In it the lung becomes dry, gray, reddish, or black, indurated, and impermeable to air.

It may occur as a primary disease, or may follow an attack of acute pneumonia. The patient gradually loses flesh and strength; there is cough with trifling expectoration and no haemoptysis, and slight but irregular fever. The physical signs are dulness on percussion over the affected part, with feeble, harsh, or bronchial respiration, and increased vocal fremitus. When it affects the upper lobe of the lung, the diagnosis between chronic pneumonia and phthisis is very difficult. The disease is generally fatal.