552 AliXORMA/JTJES I\ MET A HOLISM 



present iu the day 's urine diacetic acid may be found, but oxybutyric 

 acid does not usually appear until the amount of acetone exceeds 1 

 gram. After this the chief increase is in the oxybutyric acid, which 

 often reaches 30 to 80 grams, whereas the diacetic acid and acetone 

 together rarely exceed 7 to 8 grams (v. Noorden). However, the 

 results obtained by most investigators do not support the regular 

 quantitative relationship described above, extremely irregular results 

 being commonly obtained; as a rule, when any one of the three ace- 

 tone bodies is present in large amounts there is an abundance of each 

 of the others. Kenneway ^- confirms Neubauer's statement that oxy- 

 butyric acid is rather constantly from 60 to 80 per cent, of the total 

 acetone bodies excreted in the urine. In the internal organs the ace- 

 tone bodies may also be detected, especiallj^ in the liver.^^ In normal 

 blood Marriott found less than 4 mg. of oxybutyric acid, and 1.5 mg. 

 of acetone and aceto-acetic acid together, per 100 c.c. ; but in diabetic 

 coma tlie figures rose as high as 45 mg. and 28 mg. respectively for 

 eacli fraction, the amount in the blood not corresponding to the 

 urinary excretion.^^'' 



Relation of Acidosis to Diabetic Coma. — Tliere seems to be lit- 

 tle room for doubt that the typical diabetic coma with "air hunger" 

 depends upon an excess of these substances in the blood — i. e., is- 

 an acid intoxication — for the following reasons: (1) The coma ap- 

 pears when the amount of organic acids in the urine is highest, and 

 is absent when there is little or none of them in the urine. (2) Be- 

 cause of the resemblance of the symptoms to those of experimental acid 

 intoxication. (3) Because of the repeated demonstration of a re- 

 duced amount of alkali in the blood, as determined by titration, and 

 a great reduction of the amount of CO, carried in the venous blood. 

 The capacity of the serum to absorb CO, in vitro is also greatly re- 

 duced, from a normal 75 per cent, to as low as 20 per cent. (Van 

 Slyke). By means of gas-chain measurements Roily ^* found that 

 by far the lowest OH values ever observed in the blood are in dia- 

 betic coma ; and Sellards ^^ showed that in diabetes the tolerance 

 for alkalies may be increased. (4) The marked improvement that 

 sometimes results from the administration of alkalies (usually sodimn 

 bicarbonate). Associated with this improvement is an elimination of 

 greath'- increased amounts of organic acids, indicating their previous 

 retention in the body because of lack of alkali with which they 

 could combine (or their liberation from combination with proteins — 

 Landau). But there are man.y cases of diabetic coma without typ- 

 ical air hunger, and it is the exception rather than the rule for alkali 

 therapy to produce a marked improvement in the fully developed 



32Biocliem. Jour., 1013 (8), .•^5.'"). 

 33SaRsa, Bioc'hcm. Zeit., 1014 (59). 3()2. 

 33a Marriott, Jour. Hiol. Chem. 1914 (18). ,'507. 

 34Miincli. mod. Woeli., 1912 (."59). 1201. 

 SBJolins iropkins IIosp. Bull., 1912 (23), 289. 



