DIGESTION IN THE SMALL INTESTINE. 395 



anaesthesia has been produced, an incision should be made in the linea alba about 

 an inch and a half long and about two inches below the xyphoid cartilage, tying 

 each bleeding-point before the abdomen is opened. On pushing aside or tearing 

 through the omentum with the forefinger of the right hand, and carrying the 

 finger well down below the liver, a dense band may be felt running from the 

 liver to the duodenum, and consisting of the hepatic vessels, nerve, and common 

 bile-duct. Hooking the forefinger under this band, and drawing it carefully and 

 slowly forward, a blunt hook may be passed under it with the free hand, and the 

 vessels drawn out of the wound. They can be prevented from retracting into the 

 abdominal cavity by pushing the hook through so that the vessels lie upon its 

 handle, which rests transversely over the wound. The duct is easily isolated and 

 ligated at its entrance to the duodenum to secure the small blood-vessels on its 

 surface, and the cannula inserted and tied in the duct. On removing the stilette 

 from the cannula, a few drops of bile immediately escape. Probably, however, 

 a similar method, and one less likely to wound the hepatic blood-vessels, is to 

 open the abdomen at the right margin of the right rectus muscle, and then follow 

 the duodenum, which appears in the wound, and may be recognized by its large 

 size and absence of mesentery, up toward the stomach, where the duct may be 

 readily isolated and divided at its insertion into the duodenum. 



Permanent biliary fistulas may also be made quite readily in dogs, and have 

 been undertaken to decide the question as to the excrementitious nature of the 

 bile. For this purpose the gall-bladder is selected for the fistula instead of the 

 ductus choledochus. The abdomen is opened in the median line, or, preferably, 

 at the right border of the right rectus muscle, care being taken not to wound the 

 large vessels which cross the wound on the inner surface of the abdomen, and 

 the common bile-duct isolated as before. It is then ligated close to its entrance 

 into the intestine and at its junction with the cystic duct, and the intermediate 

 portion excised. 



The gall-bladder is then drawn down and fixed to the edges of the wound. 

 The operation may then be suspended until adhesion has occurred between the 

 walls of the bladder and the edges of the wound, and the bladder then opened ; 

 or it may be treated in the same manner as when making gastric fistulae, and a 

 cannula similar to the one employed in making gastric fistula? inserted at once. 

 In this mode of operation the object has been to exclude the bile entirely from 

 the intestine ; but Schiff has shown that less pressure is required to make the 

 bile pass from the hepatic duct into the gall-bladder than to force it through the 

 common duct into the intestine. This excision, then, of the common duct is 

 entirely unnecessary, apart from the fact that it sometimes fails in its object by 

 becoming restored ; since as long as the cystic fistula is kept open the bile passes 

 out of the wound, but when the cannula is closed it passes as normally into the 

 duodenum. 



When the operation for the formation of a permanent biliary fistula 

 succeeds, and all the bile is conducted outside of the bod}', animals 

 rapidly lose weight and eventually die, under ordinary circumstances, 

 under the phenomena of starvation. Such a result depends upon the inter- 

 ference with the digestion of fats and upon the direct loss of bile salts. 

 Thus, Yoit has found that a dog weighing twenty kilos, which in its 

 normal condition was able to digest from one hundred and fifty to two 

 hundred grammes of fat, absorbing 99 per cent, of this amount, was only 

 able, after a permanent biliary fistula was established, to absorb 40 per 

 cent, of the fat given. The loss of such an amount of fat through im- 

 perfect absorption naturally produces a disturbance of nutritive equi- 

 librium. An animal which before the operation is able to preserve its 

 nutritive balance with a certain amount of meat and fat, is unable to do 

 this after the performance of a biliary fistula, and is compelled to call on 



