CHAP. III.] THE BLOOD IN DISEASE. 1G9 



which are included under the term diabetic coma. In reality, the first 

 symptoms are those of a very remarkable dyspnoea, in which there is 

 equal exaggeration of inspiratory and expiratory movements ; usually 

 it is only after this has existed for some hours that the patient, who 

 has been becoming more and more prostrate, sinks into a state of 

 coma and dies. 



The peculiar ethereal smell exhaled by the breath of diabetics 

 had long been noticed, but it was Fetters who first pointed out that 

 in certain cases of diabetic coma, the apartment in which the patient 

 is confined acquires a peculiar odour, and that on distilling the urine 

 and even the blood of the patient, there is obtained a distillate which 

 contains traces of acetone. 



Fetters based on these facts the theory that the phenomena of 

 diabetic corna depend upon a disengagement of acetone in the living 

 blood, that they are the symptoms, indeed, of a poisoning by acetone, 

 Acetonaemia. 



That the blood in these cases does evolve acetone in small quan- 

 tities is proved by the concurrent testimony of several observers, 

 though it is very probable that the body does not exist free in the 

 blood, but is derived from the splitting up of ethyl-diacetic acid 1 . 



There are however some serious objections to accepting the 

 acetonaemic theory of diabetic coma. In the first place, diabetics 

 sometimes evolve the most marked acetone (?) smell, without any of 

 the symptoms of diabetic coma being present ; in the second place, the 

 administration of very large doses of acetone is required in order to 

 produce any marked physiological symptoms, which even when pro- 

 duced, are by no means identical with those of diabetic coma. 



It has been averred that when acetone is added to blood, there is 

 produced a white creamy appearance exactly similar to that which 

 has been observed, especially of late, in certain fatal cases of diabetic 

 coma. As has been shewn by Sanders and Hamilton, this statement is 

 erroneous. Acetone dissolved in alcohol and added in very small quan- 

 tities to blood, leads to no morphological change ; if added in larger 

 quantities it produces a coagulation of the proteids of the serum and 

 a solution of the coloured corpuscles, as has been shewn by Rupstein. 



In a case of diabetes, which ultimately ended by coma, which 

 came under the Author's notice, the patient for some time evolved an 

 intense ethereal smell, which attracted the attention of patients in the 

 ward ; during the diabetic coma which preceded death, the acetone (?) 

 smell had diminished and the blood had only a faint smell of acetone. 



1 C 6 H 9 Na0 3 + 2H 2 = C 8 H 6 + C 2 H 6 + NaHC0 3 . 



Sodium ethyl- Water Acetone Alcohol Sodium hydric 



diacetate Carbonate. 



This is the equation by which Eupstein (Centralblatt, 1874, No. 55) explains the forma- 

 tion of acetone in the system from ethyl-diacetic acid. 



In support of this theory is the fact that the urine of diabetics gives with Fe 2 C1 6 a 

 reddish brown colouration which disappears on the addition of HC1, or on boiling 

 properties which are possessed by ethyl-diacetic acid. 



This subject will be discussed again in connection with the urine in diabetes. 



