101 Article "Empyema," Cyc. Prac. Med., vol. ii.
102 Pleurisie purulente, (Moutard-Martin), Paris, 1872.
103 "De l'Examen histologique des Liquides, etc.," Soc. Méd. des Hôp., 1878.
104 See section on [Hemorrhagic Pleurisies].
105 Traité d'Anatomie path., Paris, 1872.
106 Brit. Med. Journ., Dec., 1877.
107 Thèse de Paris, 1865.
ETIOLOGY.—The causes of purulent pleurisies are divided into local or traumatic, which are well ascertained and defined; and the general, the action of which is uncertain. Among the first are wounds of the chest, fractures or caries of the ribs, phlegmonous abscesses of the walls of the chest, effusions of blood, pathological liquids, pulmonary gangrene, rupture of tubercular cavities, and other injuries from adjacent organs, especially of those where pus is discharged into the cavity, for the presence of pus engenders pus. Thoracentesis has been accused of converting serous into purulent pleurisies by the admission of air into the pleural cavity. If the atmosphere admitted is contaminated by germs, we must acknowledge that such a result is possible. By the older methods, previous to the adoption of Reybard's protected canula, such a result may have been produced. We can thus, in a measure at least, account for the great mortality in cases operated upon. But since the adoption of the protected orifices of the small aspirating trocar of Wyman and the capillary perforating needles of Dieulafoy, we question whether, with such an insignificant puncture and the complete exclusion of air, thoracentesis can be justly accused of producing such serious mischief. Trousseau108 earnestly denied such a deleterious effect of the operation in his day. We have now not only the results obtained by Demarquay, Leconte, and Manotte of injecting air into the pleural cavities of inferior animals, but we have the bold experiments of Matice, who, convinced that air could not have any bad influence, actually had the audacity to perform the operation a number of times, allowing the air to enter freely through the canula. From numerous observations there resulted the fact, unsuspected by many, that air, penetrating freely to replace the liquid extracted, never gave rise to purulence in pleurisy; that, owing to its rapid absorption, it did not in the least interfere with the expansion of the lungs; in short, that it produced no accident whatever. While admitting the force of Matice's conclusions, we think it preferable to avoid the possibility of doing harm.
108 Loc. cit.
GENERAL CAUSES.—We have shown that secondary pleurisies frequently occur in the course of convalescence from eruptive diseases, measles, small-pox, and especially scarlet fever, and that they are purulent in their nature. The puerperal condition predisposes to suppurative inflammations of the serous membranes, and pleurisies in lying-in women are almost always purulent. In rheumatism, gout, and delirium tremens, and albuminuria as a rule, the pleuritic effusion is serous. It is purulent in persons suffering from severe injuries and among men exhausted by over-work or by alcoholic excesses, or protracted obscure diseases, such as typhoid fever and pyæmia. Analyses of the cases in which purulent transformation has occurred show that tubercles of the lung have only a minor influence in its production—only 34 per cent. of the whole number. Attimont's109 observations were founded upon 130 cases, 80 of which recovered; of the remaining 50 that died, he found tubercle in only 9 cases. Sometimes malhygienic conditions and insufficient alimentation may account for them. Men are more subject to this disease than women in the proportion of 8 to 1,110 and young children oftener suffer from purulent pleurisy than adults. It is not easy to explain the transformation of serum into pus in pleuritic effusions that have existed for some time where there have been no grave symptoms. Imprudent exposure, affecting the general health, may thus produce disastrous results. This occurs so frequently that purulent pleurisies are generally called chronic pleurisies. There are cases where neither local nor general conditions explain the transformation of serous into purulent effusions in the chest.