742 HENRY G. BARBOUR 



dioxid content nins essentially parallel to carbon dioxid capacity (i. e., 

 varies with the alkali reserve of the blood), acapnia is a variety of acidosis. 



Y. Henderson and Underbill showed that a lowered carbon dioxid 

 content of the blood was associated after piqure, pancreatectomy, light 

 etherization, excessive artificial respiration and in other conditions with 

 hyperglycemia and glycosuria. 



Carbon Monoxid. Clearly an asphyxial poison, carbon monoxid 

 forms a firm combination with hemoglobin for which it has two hundred 

 times the affinity of oxygen. When an atmosphere containing 0.05 per 

 cent carbon monoxid is inhaled oxygen transportation is seriously ham- 

 pered ; 0.2 per cent is generally fatal, the hemoglobin then being about 

 60 per cent saturated with the poison (Haldane(fr)). Carbon monoxid 

 acts only by displacing oxygen, for when oxygen is breathed under two 

 atmospheres pressure (which renders an animal independent of its hemo- 

 globin) the addition of carbon monoxid in any amount produces no 

 symptoms. Furthermore, in gas poisoning cases, oxygen if administered 

 soon enough, which is rarely feasible, rapidly dispels the symptoms. 

 Hemoglobin-free animals, for example, insects, exhibit no deleterious 

 effects in the presence of carbon monoxid. 



Blood Gases. Saiki and "Wakayama in carbon monoxid poisoning 

 in rabbits found the carbon dioxid of the blood reduced from 30 to 5.21 

 volumes per cent; in dogs from 30-40 to 3.22 volumes per cent The 

 blood oxygen in the two species was reduced respectively from 12.64 to 

 7.62 per cent and from 20 to 2.01 per cent. 



The low carbon dioxid content is not due to lessened carbon dioxid 

 production, for, as Hans Meyer has shown, the latter must be very mark- 

 edly reduced to produce even a slight diminution of the blood carbon 

 dioxid content; it indicates rather a reduced alkalinity of the blood. 

 Araki confirmed this by tritration and Saito and Katsuyama showed 

 further an increase in the blood lactic acid in hens from 0.02G9 to 0.1227 

 per cent. The fact that in dogs the blood carbon dioxid content is dimin- 

 ished so imich more profoundly after carbon monoxid than after acid 

 administration does not militate against acid production being the cause 

 of this acapnia, for Loewy reminds us that acid feeding by mouth is one 

 thing and acid formation in the tissues another; in the latter case, as, for 

 example, in carbon monoxid poisoning, the fixed alkali becomes attacked 

 before the ammonia regulation comes into play. Spiro, in fact, has demon- 

 strated a marked acapnia as a result of the injection of acids intraven- 

 ously (the ammonia regulation being thus more or less evaded). The 

 occurrence of acidosis may satisfactorily reattributed to oxygen deficiency. 



Total Metabolism. Bock found in a dog subjected to an atmosphere 

 of 0.2 per cent carbon monoxid (leaving less than half the hemoglobin 

 saturated with oxygen) that the oxygen intake remained practically un- 

 changed, while there was a considerable rise in the carbon dioxid excre- 



