HYDROTHORAX. 149 



The moment the trocar has cut its way through the wall of 

 the side, which will be felt by the cessation of resistance, 

 the stillet is to be withdrawn, leaving the canula within the 

 wound, through which it must now be pushed as far as it 

 will go, or until fluid runs out in a copious stream. Though 

 the water may gush out at first, it seldom continues flowing 

 long in a full stream ; often, indeed, its stream becomes 

 interrupted, or altogether arrested, either by the lungs 

 coming against the mouth of the canula, or some flakes of 

 lymph collecting about it or flowing into it, to remove 

 which it becomes necessary, from time to time, to pass a 

 whalebone or iron probe through the canula. From one or 

 other of these causes, it has happened that no water has 

 followed the introduction of the trocar, even though the 

 cavity perforated has been all the while full; as a general 

 rule, therefore, do not withdraw the canula when no fluid 

 issues, until quite assured that it is fairly within the cavity, 

 and that its mouth is free from all obstruction. When the 

 cavity is so nearly emptied of its water that fluid only issues 

 in jets each time the lungs expand, the canula ought to be 

 immediately withdrawn, else, during the intervals while no 

 water is flowing, air will be apt to rush into the chest; and 

 air within the thorax is said to do harm, and therefore we 

 must avoid it. The valvular covering aff'orded by the return 

 of the skin drawn to one side will efi'ectually close the 

 wound after the operation. 



Hydrothorax is not necessarily incurable. — The 

 cases I have related prove this. Under what circumstances 

 have we most chance of curing ? Let us consult our cases 

 again. We find that in all of them the water was confined 

 to one — and that the right — side : the quantity in the left 

 cavity was too inconsiderable to notice. This then — as 

 appears in theory, so in practice — constitutes a favorable 

 indication. We find again — with the exception of Magot^s 

 case, in which the quantity of water was inconsiderable, 

 and which, after all, looks like a relapse — that two of them 

 were tapped in the second, the other in the fourth week after 

 attack : none, therefore, could be called old or chronic 



