52 DONALD D. VAN SLYKE 



Magnus-Levy (<?)( 1899) completed the demonstration by showing that the 

 chief source of the acid is incompletely burned fat, that in diabetic acidosis 

 the rate of formation of beta-hydroxybutyric acid may exceed 100 grams 

 per day (equivalent to 1 liter of N/l acid), that the amounts found in the 

 body at death are sufficient to cause fatal intoxication, and that even after 

 the onset of coma death may sometimes be prevented by sodium bicarbonate 

 administration. Magnus-Levy also emphasized the fact that, although 

 most deaths in diabetic coma appear directly caused by acid intoxication, 

 death may occur from other causes, and without premortal acid intoxica- 

 tion. 



The terminal uremic coma of nephritis was pointed out by Kussmaul 

 (1874) to be similar in its dyspnea to diabetic coma, and Jaksch(/) (1888) 

 by means of a simple method for titrating the alkali content of the blood 

 obtained results indicating the probable presence of acid intoxication, 

 which has been confirmed with modern methods by Straub and Schlayer 

 (1912) and Peabody(c) (e) (1914). The acidosis of nephritis differs 

 notably from that of diabetes in the fact that the ketone acids, beta-hydroxy- 

 butyric and acetoacetic, do not occur in the former. Presumably the 

 acidosis of nephritis is due to failure to excrete the acids produced by 

 normal metabolism, rather than, as in diabetes, to abnormal acid produc- 

 tion. Further investigations have indicated a role of acid intoxication in 

 other conditions, some caused by the ketone acids (e. g., cyclic vomiting 

 in children), others caused by unknown acids (ether narcosis and certain 

 types of diarrhea in infants) . Some of these conditions will be considered 

 after a discussion of the nature of the changes caused by entrance of acids 

 into the body at a rate exceeding that of their elimination. 



The first, unified exposition of the physiological and physico-chemical 

 mechanisms by which the body maintains its normal acid-base balance 

 was published by Lawrence J. Henderson(a) (1909) in a monograph which 

 forms the basis of our present conceptions, and which, both in its view- 

 point and in its details, may be accepted at present, with revision only to 

 include additional facts that have been uncovered during the interim. 



The Nature of Acidosis 



Acidosis may be broadly defined as an abnormal condition caused by 

 acid retention, that is, by the formation or absorption of acids at a rate 

 exceeding that of their elimination. Such retention may be considered 



when acetoacetic acid is present. These three substances are called the "acetone 

 bodies." from the fact that the other two are readily converted into acetone, or "ketone 

 bodies," from the fact that the acetone and diacetic acid are ketones. When in the 

 blood or urine one of them is present it is apparently always accompanied by the 

 other two; consequently a test for acetone or acetoacetic acid is a test for all three 

 of the substances. Atypical comas also occur, due to collapse from causes other than 

 acid intoxication, and differentiated from it by absence of air-hunger and of great 

 ketonuria. 



