408 



THE RESPIRATION 



of these conditions is that the interference with the pulmonary func- 

 tion has prevented proper removal of free C0 2 from the blood, to com- 

 bine with which the alkali has increased probably by diminution in its 

 excretion by the kidney. The increase in alkali will raise the buffer 

 action of the blood for C0 2 . 



THE OXYGEN REQUIREMENT OF THE TISSUES 



In order to ascertain the average 2 requirement of the different tis- 

 sues of the body, it is necessary to adopt as a standard of measurement 

 the amount of 2 in c.c. absorbed per gram of tissue per minute. To ob- 

 tain it we must know: (1) the weight of the particular organ or tissue 

 under investigation; (2) the bloodflow through the vessels of the organ 

 in c.c. per minute; and (3) the different percentages of 2 in the arterial 

 and venous blood of the tissue. It would be beyond the scope of this 

 book to review in any detail the many experimental investigations which 

 have been undertaken in this connection. A iew of the most recent 

 and important results are given in the accompanying table from Halli- 

 burton 's Physiology: 



In the order of their oxygen requirements, or the coefficient of oxida- 

 tion, as it is called, the tissues may be divided into four groups ; glandular, 

 muscular, connective, and nervous. The nervous tissues should possibly 



