The Metabolism in Diseases of 

 Respiration and Circulation 



FRANCIS W. PEABODY 



AND 



EDNA H. TOMPKINS 



BOSTON 



The pathological alterations of the metabolism which occur in the 

 diseases of the circulatory and respiratory systems are in general so 

 similar that they may be conveniently taken up together. In the present 

 consideration attention will be paid only to those changes which are the 

 direct result of disturbances of the functions of the respiration or circula- 

 tion. This, of course, does not include the processes other than functional 

 occurring in pneumonia, pulmonary tuberculosis and analogous con- 

 ditions, which are the result of infection or toxemia and which are con- 

 sidered separately under the appropriate heading. The early literature 

 has been adequately reviewed by Matthes(c) in von Noorden's "Metabolism 

 and Practical Medicine" (1907), and is only referred to here incidentally. 



In relation to the metabolism of the organism, the respiration and the 

 circulation perform the important functions of supplying oxygen to the 

 tissues, removing the gaseous and non-volatile waste products of cellular 

 activity, and transporting metabolites from one part of the body to 

 another. As would be expected, therefore, disease of the circulation and 

 respiration may affect the metabolism in a variety of ways. In the first 

 place, there may be an interference with gaseous exchange, either between 

 the air in the lungs and the blood (external respiration), or between the 

 blood and the tissues (internal respiration), with a resulting lack of 

 oxygen or accumulation of carbon dioxid. As will be seen, the latter, 

 probably owing to the high rate of diffusion of carbon dioxid, is of com- 

 paratively little practical importance, while insufficient oxygen may pro- 

 duce most serious effects. Disturbances of gaseous exchange in the lungs, 

 which may be due to such processes as bronchitis, pulmonary edema, and 

 consolidation, can be studied by means of analysis of the gases in the 

 blood and in the alveolar air. Disturbances of gaseous exchange in the 

 internal respiration, on the other hand, such as might be due to circulatory 

 failure, or indirectly to disturbances in the external respiration, are much 



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