Blood in Intestinal Obstruction 



359 



dilute the blood 1-5 with water and after laking has been com- 

 pleted, to precipitate the proteins with an equal volume of 5 per 

 cent, trichloracetic acid. The acid then has a concentration of 

 2.5 per cent, of the total volume. 



In simple but complete experimental intestinal obstruction the 

 first change noted in the blood was a rise in the non-protein nitro- 

 gen from 36-90 mg. This rise is more rapid, the nearer the ob- 

 struction is placed to the duodenum, where the toxemia is most 

 severe, indicating a corresponding increase in the rest-nitrogen, 

 Since the dogs are on a water diet, this nitrogen must be of 

 endogenous origin. A similar rise in non-protein nitrogen is noted 

 in the segmental type of obstruction. However, this rise is much 

 greater and more rapid than simple obstruction occurring at the 

 same level. In but one animal the urea nitrogen rose above nor- 

 mal limits, 21.5 milligrams. The non-protein nitrogen, however, 

 was 47 milligrams which was more than twice the urea nitrogen. 



All the animals showed a decrease in the alkaline reserve as 

 indicated by the carbon dioxide combining power. In obstruc- 

 tions of the segmental type the drop in the carbon dioxide com- 

 bining power is more marked. 



In the clinical cases reported, an increase in the non-protein 

 nitrogen from 36 to 83 milligrams occurred. This is in accord 

 with the experimental findings. In many cases the urea nitrogen 

 is above normal, but it forms less than fifty per cent, of the non- 

 protein nitrogen. The uric acid is definitely increased above 

 normal 4-11 mg. per 100 c.c. Following operation, with relief 

 of obstruction in most instances there is a steady decrease in non- 

 protein nitrogen. This decrease in non-protein nitrogen was 

 found to be associated with a clinical improvement in the pa- 

 tient's condition. 



In one case there was a rapid rise in non-protein nitrogen fol- 

 lowing operation from 51 to 83 mg. in 4 days. Following a 

 stormy convalescence the patient recovered. In this instance 

 several feet of gut with questionable viability were returned to 

 the peritoneal cavity. The increase in urea, uric acid and crea- 

 tinine of the blood appears to be subsequent to a rise in the non- 

 protein nitrogen. 



When there is an accumulation of the nitrogenous waste prod- 

 ucts they follow the order of retention characteristic of renal 

 impairment, namely a successive rise in uric acid, urea nitrogen 

 and creatinine. 



