OF THE ALIMENTARY CANAL 105 



from chronic constipation. The bismuth meal 

 normally reaches the pelvic colon in about twenty- 

 four hours. 



The existence of currents of antiperistalsis is 

 very important surgically. Many patients on 

 whom ileosigmoidostomy (turning the ileum into 

 the pelvic colon or sigmoid) has been performed for 

 growth of the ascending colon have suffered great 

 subsequent discomfort from the passage of gas and 

 faeces into the blind loop of colon, from the opening 

 into the sigmoid up into the descending colon, and 

 so round towards the caecum. In some cases a 

 second operation has been necessary. In all ana- 

 stomoses and excisions of the large intestine this 

 physiological factor must be calculated upon and 

 provided for. In some cases an appendicostomy has 

 been performed to allow flatus to escape and to make 

 lavage possible. 



Before turning from the motor functions of the 

 intestines, another experimental observation merits 

 attention. Pawlow found that strong stimulation of 

 any sensory nerves might cause, in dogs, prolonged 

 reflex arrest of peristalsis. Injury of abdominal 

 viscera was particularly likely to do so. Cannon and 

 Murphy have shown that even gentle manipulation 

 of the bowel causes cessation of all intestinal 

 movements for three hours or more. The condition 

 might be described as " intestinal shock." It is of 

 great surgical importance. Arrest of peristalsis, quite 

 apart from peritonitis, occasionally follows strangu- 

 lated hernia, even after successful operation ; it may 

 accompany gall-stone colic, and it may even occur as 



