270 DISEASES OF THE PLEURA. 



disease with the form of pleuritis now under consideration, is generally 

 of briefer duration than the other symptoms of pneumonia. Perhaps 

 this is because the pleural surfaces cease sliding upon one another, 

 where a large portion of the lung has become infiltrated. But even 

 when the disease occurs spontaneously, or when it supervenes in 

 clironic disease of the lung, the pain usually ceases in a few days, 

 especially if properly treated. Its persistence for weeks is an excep- 

 tional occurrence, and should cause suspicion of grave disease of the 

 lung. 



Pleurisy with profuse sero-fibrinous exudation sets in quite often, 

 w ith violent general phenomena, and severe symptoms of local disease, 

 in a manner very like the commencement of pneumonia. The malady 

 begins acutely, and runs an acute course. Ushered in by a severe 

 rigor, it is followed by intense fever, with the full and frequent pulse, 

 the headache and pain in the back and limbs, the coated tongue, and 

 the parching thirst, which we see in almost all violent inflammatory 

 diseases. There may, however, be more than one chill, and there are 

 often several, the succession of which may take on so well-marked a 

 tertian type, that it is quite possible to mistake an incipient pleurisy 

 for an intermitting fever. A sharp pain, usually referred to the side 

 of the chest, is also felt at the beginning of this variety of pleurisy, 

 into which the form last described often passes, the exudation becom- 

 ing more copious and richer in serum. As the disease advances, the 

 pain abates somewhat, and often ceases altogether, before the pleurisy 

 has attained its climax, or especially before the effusion is complete. 

 The cough, which scarcely ever fails, and which is often extremely 

 distressing and persistent, is sometimes plainly attributable to the col- 

 lateral hyperaemia and collateral cedema of the uncompressed part of 

 the lung. At other times its source is obscure. Besides these symp- 

 toms, there is dyspnoea, which becomes aggravated as the effusion 

 increases, and which often becomes extremely severe. It is important 

 to bear in mind the fact that a part only of the dyspnoea is caused by 

 pressure of the effusion upon a portion of the lung, and that the col- 

 lateral hypeKEmia and cedema arising in the uncompressed portion, and 

 by which the breathing surface of the latter is materially diminished, 

 play an important part in the production of dyspnoea. At all events, 

 even where the effusion is very large, the difficulty of breathing dimin- 

 ishes, and often ceases altogether, just as it does in croupous pneumo- 

 nia, as soon as the fever abates, and with it the need of additional 

 oxygen. 



After increasing in intensity for six or eight days, a sudden im- 

 provement may take place, just as in croupous pneumonia, the general 

 disturbance and dyspnoea undergoing a marked decrease, or even ceas- 



