Pneumothorax

Regarded apart from clinical experience pneumothorax would inevitably be considered as a condition having a peculiarly distinct and definite onset, and attended by acute manifestations which could not fail to impress themselves upon the attention of the ?patient. A rush of air into the pleural cavity, which, in the nature of things, can hardly be other than sudden, and which involves a prompt compression and folding-up of the lung, often with extreme mechanical displacement of the heart, and a complete alteration of the pressure conditions within the thorax,'is an event which," on theoretical grounds, would be naturally expected to produce an acute and unmistakable subjective experience. That, in ?pertain cases, this'is so, is beyond question. Bub it 18 not an invariable or even the more usual order of events. Indeed, it is hardly too much to say "that, in the majority of cases, pneumothorax develops without any recognition on the part of the patient ar*d often also escapes detection by the physician. This general proposition finds full illustration in the report decently issued by the Pathological Department of the Brompton Hospital,1 which includes a record of the post-mortem examinations made in the department during the three years ending April 1903. Amongst these are accounts of autopsies on 19 cases tuberculous pneumothorax, and in no less than eight of these the personal history was free from any ?^cute event suggesting the date of origin of the Pneumothorax. Further, there were in these cases ?ew or no symptoms indicating the existence of such a condition, and the discovery was either made during the physical examination or at the autopsy opening the chest. This record is in entire harmony with the experience of all physicians who have bad considerable practice in diseases of the chest, ^he explanation of this absence of symptoms which on a priori grounds might have been expected to attend a condition of pneumothorax is in some cases a fairly obvious one. Prior to the occurrence of the pneumothorax, more or less extensive adhesions have oeen formed between the parietal and visceral layers ^ the pleura and thus when, by rupture of the latter, is admitted into the pleural cavity the extent^ of the inrush is limited and confined, and corresponding to this the compression of the lung is only partial. his is illustrated in four out of the eight cases above ^lluded to, and it is a frequent occurrence in pneumothorax developing in the course of pulmonary phthisis. But it is not true in all cases, as is shown *n the report to which allusion has just been made. * or in no less than four of the eight cases of pneumothorax existing without symptoms the pneumothorax Was found to be either "total" or "practically total." In an these instances it is to be observed that the affected lung was the subject of chronic pulmonary tuberculosis or of acute caseous disease with ?aPid softening, and thus it may be presumed that a iarge part of the lung was out of action prior to the occurrence of the pneumothorax, and that it connbuted therefore but a small share to the success of the thoracic respiration. Hence the compression of he lung in these circumstances would not inflict any special embarrassment on the respiratory efficiency, and anything like sudden dyspnoea as an index of the supervention of the pneumothorax would fail to