TORSION, FORCIPRESSURE, AND ACUPRESSURE. 169 



forceps, and immediately ligatured ; this prevents the seat of operation 

 being obscured with blood. 



In human surger}-, when dealing with deeply situated vessels, which 

 it would be difficult to isolate and ligature, the forceps are sometimes 

 left in the wound until the blood-vessel has become entirely filled 

 with clot. In such case they are fixed between the layers of the 

 dressing or between the lips of the wound, and removed at the end of 

 twenty-four to forty-eight hours, according to the size of the vessel to 

 which they have been applied. Needless to say, forceps, threads, and 

 instruments must all be aseptic, an indispensable condition if one 

 wishes to effect primary union or prevent accidental infection. 



Acupressure never found much favour in veterinary practice as com- 

 pared with human surgery, because animals are too difficult to control. 

 At the present day it has lost much Fig. 196/;. 



of its value, inasmuch as materials 

 for ligaturing vessels are available 

 which can be left permanently in 

 position without danger. Acupres- 

 sure is effected by thrusting a pin 

 vertically into the soft tissues about 



three eighths to three fourths of an 



inch from the arter}^, carrying it in 



a horizontal direction over or under 



the artery, and causing it to emerge 



a similar distance on the opposite 



side of the vessel. The opening of p^^^ ^^g^^ iges.-Method of practising 



the artery is thus pressed either acupressure. 



against soft parts, or, better still, against a bone (see Figs. 196 a and 



196 b). When this is ineffective or impossible to carry out, two needles 



are employed, one passed below, the other above the vessel. 



The elastic ligature is an excellent means of stopping bleeding. 

 Applied with tension to a certain thickness of living tissue the rubber 

 loop continues to diminish in diameter, and to cut until it becomes 

 entirely relaxed. This constitutes a great advantage over the simple 

 ligature, the action of which, though at first severe, rapidly diminishes 

 and soon comes to a standstill, necessitating a new ligature being 

 applied, or the old one tightened soon after the superficial layers of 

 tissue have been divided. The elastic loop has no action on inert 

 bodies, even though comparatively soft, or on dead tissues, but rapidly 

 divides all living tissues like skin, muscle, vessels, tendons, or even bone. 

 Nothing living can resist it. Division proceeds without haemorrhage, 



