The Operation of the Paracentesis Thoracis, proposed for Air 

 in the Chest, with some Remarks on the Emphysema, and on 

 Wounds of the Lungs in general ; by Mr. William Hewson, 

 Reader of Anatomy. Communicated by Dr. Hunter. Read 

 June 15, 1767 (CLII). 



ALTHOUGH the emphysema has been of late more successfully 

 treated than formerly, yet I have been led to think that some- 

 thing further might be attempted towards a more certain and 

 a more speedy cure of that distemper. 



The improvement which has occurred to me, and which I 

 shall venture to lay before the Society, is the operation of the 

 paracentesis thoracis, in order to let the air out of the chest ; 

 for that the confinement of the air in that cavity occasions the 

 worst symptoms in that disorder, and even death itself, I am 

 almost persuaded, partly from considering what the conse- 

 quences must be of a wound of the lungs, (for a wound there 

 is the common cause of the emphysema,) and partly from at- 

 tending to the symptoms of the disease; but chiefly from the 

 dissection of the body of a person who died under it. 



The accident which most commonly gives rise to the em- 

 physema is a fractured rib, by which the vesicles of the lungs 

 being wounded, the air escapes through them into the cavity 

 of the thorax; but as the rib, on being fractured and pushed 

 inwards, wounds the pleura, which lines the ribs and the inter- 

 costal muscles, part of the air most commonly gets through 

 the pleura and those lacerated muscles into the cellular mem- 



(CLII.) From the * Medical Observations and Inquiries, by a Society 

 of Physicians in London,' vol. iii, p. 3/2, 8vo, London, 1767. The 

 second Dr. Monro had previously proposed to let out the air from the 

 pleura in cases similar to those mentioned in this paper, as Hewson 

 has more fully explained in the beginning of the Appendix to the 

 First Part of the ' Experimental Inquiries,' pp. 91 etseq. of this volume. 



