METABOLISM IN RESPIRATION AND CIRCULATION 545 



reduced, therefore, that one may expect any changes in the metabolism. 

 This is found to be true clinically, for in patients with cardiac or respira- 

 tory disease in a "compensated" state, or without symptoms at rest, no 

 changes in the metabolism have been observed. 



Before taking up in detail the effects, of disease of the circulation of 

 respiration on the course of the various chemical changes in the body, 

 it may be well to consider the oxidative processes as a whole, in their 

 qualitative and quantitative relationships, as is shown by determinations 

 of the oxygen consumption and carbon dioxid production. Fundamental 

 abnormalities in the general method of heat production might furthermore 

 manifest themselves in the respiratory quotient, which is found by the 

 various methods used in determining basal metabolism. Several observa- 

 tions (Kraus(c), Grafe(6)) of extraordinarily low respiratory quotients 

 in patients with heart disease suggested that there might be some qualita- 

 tive abnormality of the metabolism in this condition, but later investiga- 

 tions have failed to confirm this, and make it probable that the low quo- 

 tients were due to technical errors. Peabody, Meyer and DuBois studied 

 the basal metabolism of patients with cardiac, or cardiorenal disease in the 

 bed calorimeter of the Russell Sage Institute of Pathology at the Bellevue 

 Hospital, New York. They found complete agreement in the results ob- 

 tained by the direct and indirect methods of calorimetry, and the respira- 

 tory quotients were all within normal limits. This indicates that there 

 is no profound alteration of the intermediary metabolism. The patients 

 on whom these observations were made were, in part, cases with com- 

 pletely compensated cardiac lesions and, in part, cases with moderate 

 insufficiency, as evidenced by slight difficulty with breathing even while 

 at rest, but the series does not include any severely decompensated pa- 

 tients. There are obvious technical reasons which make it difficult, if not 

 impossible, to determine the gaseous exchange of extremely sick patients 

 with circulatory or respiratory diseases, but in the absence of actual ob- 

 servations on such subjects, no definite statement can be made with regard 

 to the occurrence of qualitative changes in the metabolism in severe cases. 

 The possibility of the existence in very sick patients, of an interference 

 with the oxygen supply to the tissues, or with the removal of carbon dioxid, 

 circumstances which would alter the respiratory quotient, must be borne 

 in mind. This subject will be referred to again subsequently. 



Quantitative studies of the basal metabolism or heat production were 

 also made by Peabody, Meyers and DuBois. The results showed that in 

 patients with compensated heart lesions the basal metabolism is within 

 normal limits, but that in patients with dyspnea the metabolism may be 

 increased 25 to 50 per cent above the average normal. This increase is 

 not constant even in dyspneic patients, however, for it occurred in only 

 nine out of the twelve subjects and was marked in only five. The cause of 

 the increase of metabolism is not clear, but the evidence does not indicate 



