Experimental Uremia. Uremic Enteritis.

Abstract

The objects of this research were to determine what effect uremia has on the Gastro-intestinal canal and to explain if possible the causation of uremia on a chemical basis. Uremia was produced in dogs by repeated injections of 10% to 20% urea solution (sterile) intravenously, giving 200 cc. daily for 3 days at the rate of 5 cc per minute (Woodyatt pump). One ureter had been ligated in many instances and in other cases the ureter had been intact. The blood, urine and feces were collected at 24 hour intervals for chemical determinations and at necropsy gross and microscopic tissue studies were made. In about 40% of the dogs a picture similar to that of uremic coma, the so-called “Kussmaul picture”, was produced after a single injection of 200 cc. of 10% or 20% urea solution and in practically 100% of the animals coma was invariably produced after the 2nd or 3rd injection. The outstanding features of the chemical analysis may be grouped as follows: (a) A progressive acidoses demonstrated by a marked fall in CO2 content, (b) A marked fall in blood proteins evident in the decrease of the refractometric index, (c) Marked rise in urine chlorides. (d) Disturbance in the calcium-potassium ratio—the ratio approaching 1 or 1+. (e) Marked increase in blood urea. Upon careful analysis of the output of urea in the form of ammonia nitrogen and urea-nitrogen, it is evident that only 25% to 30% is recovered in the urine and feces. A very interesting observation was made by Andrews that the identical chemical picture was produced by intravenous injection of a 5% sodium-chloride solution. We suggests that “The disturbance of the osmotic equilibrium resulting from maintaining high blood urea levels for a prolonged period causes or is associated with changes in the mineral salt balance which bears a striking resemblance of that found in human uremia or experimental uremia from sodium chloride injections.”