DETAILS OF ANTISEPTIC SURGERY 217 



the ends of each thread being knotted at a distance of one or two inches from 

 the tube. These knotted threads being placed straight upon the skin, one at 

 each side, the knots exert friction upon the dressing bound down upon them, 

 and prevent the tube from being pushed in, while the dressing itself keeps it 

 from protruding, so that the orifice hes flush with the integument. When the 

 tube has to be placed obliquely, its outer end must be cut obliquely in proportion, 

 as shown in the accompanying sketch, otherwise it is apt to become partially 

 buried and blocked up. 



Another cause may lead to partial obstruction in chronic cases, such as 

 spinal abscess — viz. the projection of fungoid masses of granulations through 

 the holes in the tube so as to interfere with its calibre, and at the same time 

 cause difficulty in extracting and reintroducing it. But this inconvenience is 

 got over by having the holes restricted to the vicinity of the deeper end of the 



tube : for it seems to be chiefly at and near the integument that the granulations 

 have this tendency to fungate ; and in cases of this kind it is only at the deeper 

 part of the tube that holes are required. 



In recent wounds I used to think it needful to take out the tubes on the 

 day after operation or accident to clear them of clotted blood. But I find this 

 is wholly unnecessary, the shrinking of the clot apparently preventing it from 

 interfering with the exit of discharge, so that a tube introduced at the time 

 of an operation may be left in for three or four days, by which time the tissues 

 around it will have been consolidated by organizing blood or lymph into a smooth 

 channel, into which the tube can be readily reinserted, which is by no means 

 always the case if it is taken out the day after operation. 



In large and deep wounds, where very free drainage is required, it is con- 

 venient, instead of using one tube of very large calibre, to insert several of smaller 

 size side by side. These, while quite as efficient as a single large one. do not 

 separate the edges of the wound so much, and they can be afterwards withdrawn 

 one after another as the discharge becomes reduced. 



LISTER U Q 



