738 DIGESTIVE APPARATUS. 



rumen may be directly punctured with a straight bistoury, and 

 after the punctured wound is sHghtly enlarged, but before the blade 

 of the bistoury is withdrawn, an improvised canula, consisting of a 

 hollow elder twig, may be introduced. Were the blade of the bistoury 

 withdrawn before the introduction of the canula, the rumen w^ould 

 be displaced, and the points punctured would no longer correspond. 



Complications, such as respiratory or circulatory syncope, attacks 

 of vertigo, etc., have been noted, but these in reality are very rare. 



Subcutaneous Emphysema. — When the canula is carelessly removed, 

 and the subcutaneous connective tissue is torn, local emphysema may 

 occur if the pressure of gas in the rumen is very great. This gas 

 enters the puncture, proceeds along the connective tissue, particularly 

 the subcutaneous connective tissue, and causes crepitant subcutaneous 

 emphysema, very easy to recognise. This emphysema may remain 

 localised in the neighbourhood of the puncture and gradually become 

 absorbed. It may, however, extend to the whole of the flank or even 

 beyond, and in exceptional cases bring about generalised subcutaneous 

 emphysema. Such very extensive emphysema as this rarely becomes 

 reabsorbed without complications. 



The suppuration which follows puncture of the rumen may assume 

 one of two forms : — 



{a) That of a little local abscess at the point of puncture, when 

 foreign matter or the microbes of suppuration have been left in the 

 path made by the withdrawal of the canula. Such abscesses are of 

 little importance. They rapidly heal if opened and treated with anti- 

 septic injections. 



{h) That of diffuse subcutaneous or interstitial suppuration following 

 accidental emphysema. 



The pressure of gas forces fragments of food material between the 

 layers of tissue, and suppuration is set up, the pus escaping by a fistula 

 at the point of puncture. Such suppuration is decidedly dangerous, 

 because it may result in necrosis of the aponeurotic layers of the 

 small oblique muscle, in which case recovery is tedious and uncertain. 



Treatment consists in laying open the orifice and fistula, and 

 making a counter opening at the lowest point of the swelling. Free 

 drainage and abundant irrigation with boiled water at the body tem- 

 perature, followed by antiseptic injections, complete the treatment. 



Peritonitis is not altogether exceptional as a sequel to puncture 

 of the rumen, if ordinary precautions are neglected or if infective 

 material or fragments of food pass into the peritoneal cavity. 



At first the condition is usually local, but it may extend and assume 

 the form of general peritonitis two or three weeks later. The symptoms 

 are those of acute peritonitis. 



