164 THE BLOOD IN DISEASES OF THE HEART. [BOOK I. 



as to assume a viscid consistency. There thus appears to be an increase 

 in the number of the coloured blood-corpuscles and even of the 

 serum-albumin. Whilst the proper salts of the serum may fall to 

 one half, the blood-corpuscles also are robbed of their mineral con- 

 stituents, their potassium and phosphoric acid diminishing. 



C. Schmidt pointed out that the blood in cholera also contains 

 urea; his method was however obviously not calculated to obtain 

 very accurate information on this point. Voit found as much as 2*43 

 grammes of urea in 1000 parts of the blood of a cholera patient, 

 and Chalvet as much as 3'60 grms in 1000 \ 



C. THE BLOOD IN DISEASES OF THE HEART. 



Mode in Through the interference which is brought about 



in the functions of other organs, especially of the 



fluence the lungs, the liver, and the kidneys, diseases of the heart 



composition often lead " in the end to marked alterations in the 



of the Wood. quality of the blood. We have only to cite the cyanosis 



which accompanies a patent foramen ovale or persistent 



ductus arteriosus to remind the reader how a mechanical lesion of the 



vascular system may interfere with the respiratory exchanges of the 



blood so markedly as to require no elaborate investigation of the gases 



of the blood to reveal it. 



In lesions of the mitral valve particularly, conditions are es- 

 tablished which, by rendering the pulmonary circulation difficult, 

 bring about changes in the lungs which soon lead to deficient oxy- 

 genation of the blood and to its concomitant symptoms ; especially is 

 this the case in mitral stenosis. The difficulty which the left auricle 

 encounters in completely emptying itself of blood, leads first of all to 

 a rise of the blood-pressure in the pulmonary capillaries, and this in 

 its turn prevents the propulsion of more than a small amount of 

 blood from the right ventricle, which in its turn reacts upon the right 

 auricle and through it upon the whole venous system. The increased 

 pressure in the latter opposing a greater resistance than normal to the 

 passage of blood from the arteries back to the heart, there is set up 

 an engorgement of vessels which soon reveals itself by congested liver 

 and kidneys, and by functional disorders of the alimentary canal, and 

 by increased transudations, which give rise to anasarca and to dropsy 

 of the serous sacs. 



Diseases of the heart lead therefore secondarily to changes in 

 various organs, which in their turn react upon the composition of the 

 blood, and the extent to which they do so depends upon the manner 

 or extent in which each organ is affected. 



Thus any great impediment to the pulmonary circulation will lead 

 directly to non-elimination of carbonic acid, and a diminution of the 

 oxygen taken up, evidenced by the blue cyanotic appearance of the 

 lips and face. A congested liver will be accompanied by the passage 



1 Quoted by Gautier, Chimie appliqute, &c. , Vol. IT. , p. 337. 



