BY II. S. HALCRO WARDLAW. 



521 



Table i. 

 Oxygen capacity, oxygen content, and percentage of hemoglobin 

 of venous blood in pneumonic influenza. 



The above table shows that there is considerable variation, 

 both in the oxygen content and the oxygen capacity of these 

 samples. The oxygen capacity varies between 13.25 and 23.2 

 ee. of oxygen, at 0°C. and 760 mm. Hg, per 100 cc. of blood, 

 The corresponding percentages of oxyhemoglobin are 71.5 and 

 125. These values, therefore, vary over a range of about 25% 

 of the average, but it is doubtful whether any significance can 

 be attached to this degree of variation. Even in normal in- 

 dividuals the number of red corpuscles in the blood varies over a 

 range at least as wide as this (from 3.5 to 6.0 million per cubic 

 mm.). From the figures available as to the normal range over 

 which the percentage of oxyhemoglobin or oxygen capacity of 

 blood varies, but there is no reason to doubt that it is approxi- 

 mately the same as that of the number of red corpuscles. 



The percentage saturation of the samples with oxygen varies 

 over a slightly wider range, from 37.9 % to 82.9 %. Here 

 again, however, the figures show no general tendency to which 

 any significance may be attached; there is certainly no tendency 

 for the percentage saturation to be low. As many figures lie 

 above the average, which has the normal value, as lie below it 

 And although 60 % is taken as the average normal oxygen satu- 

 ration of venous blood, this number is likely to be subject to 

 even greater variations than that of the oxygen capacity. Under 

 conditions of disease, in which the metabolism is abnormal, these 

 variations may be still greater, without introducing the necessity 



