ACIDOSIS ?i 



Area 2 represents the first result of lowering in blood H 2 CO 3 by a 

 respiratory stimulus other than either the blood hydrion or H 2 C0 3 con- 

 centration. The consequence is an increase in the BHCO 3 : H 2 CO 3 ratio 

 and an overalkaline reaction (increased pH). A compensating retention 

 of acid metabolites, indicated by a decreased excretion of ammonia and 

 titratable acid in the urine, sets in, and there may be even an excretion of 

 bicarbonate (Davies, Haldane, and Kennaway). As a result of these 

 compensatory processes the bicarbonate of the blood may be lowered in 

 some hours from Area 2 to Area 3 (partial compensation), and eventually 



pM 7.8 7.7 7.6 7.5 7.4 7.3 7.2 7.1 7.0 



Fig. 4. Normal and abnormal variations of the BHCO 3 and pH in serum or 

 oxalate plasma. Arterial conditions are indicated by the solid lines and curves, venous 

 by the dashed lines and curves. The curves are 4 millimols higher than those of 

 Figure 3, since the BHCO S concentration in the plasma is higher than that of the 

 whole blood by approximately 10 volumes per cent of bicarbonate C0 2 , or 4 millimols 

 of BHCO 3 per liter. 



to Area 6, where the pH is again down to its normal value (entire com- 

 pensation) . This last condition is attained when one becomes acclimatized 

 to a high altitude (Hasselbalch and Lindhard, 1915). 



The effects of uncompensated CO 2 deficit on the urine are similar 

 qualitatively to those of uncompensated alkali excess (Davies, Haldane, 

 and Kennaway). The rate of bicarbonate excretion observed, however, 

 was much less (only a fraction of a gram per hour) when the blood pH 

 was raised by overbreathing than when it was raised by administration 

 of bicarbonate. 



The ultimate clinical symptoms are again those of tetany, and have 

 been identified as such with especial clearness by Grant and Goldman 

 (1920). The characteristic signs after voluntary deep breathing for an 



