356 EDEMA 



The very high figures for effusions in nephritis and cardiac incom- 

 petence indicate the concentration of crystalloids in these fluids, and 

 support the behef that in the formation of both, osmotic pressure is 

 an important factor." 



Edema fluids are usually alkaline except when bacterial changes 

 lead to acid formation, but they are always able to neutrahze less acid 

 than the blood of the same individual (Opie). Bodon^^ found, how- 

 ever, that while they contain alkali that can be neutralized by titration 

 against acids, yet they resemble the blood in being neutral as far as 

 the presence of free OH ions is concerned. 



Protein Contents. — As indicated in the tables given previously, 

 these vary greatly in quantity in various fluids ;^^ the quantitative 

 relations of the different varieties of proteins have been less studied. 

 Serum-albumins and globuhns constitute by far the largest part of 

 the proteins, fibrinogen being scanty except in some inflammatory 

 exudates, so that coagulation very seldom occurs spontaneously; 

 pneumococcus exudates seem particularly rich in fibrinogen, which 

 coagulates rapidly and firmly. The differences in the proportion of 

 different serum proteins in transudates is attributed by A. Oswald^^ 

 to the relative viscosity of these proteins which determines their 

 ability to pass through the capillary walls. The viscosity of serum 

 proteins varies in the following increasing order: albumin, pseudo- 

 globuhn, euglobulin and fibrinogen; hence in transudates we may 

 find only the first two, or perhaps only the albumin, while in exudates 

 the two latter appear. Joachim''^ found in pleural transudates and 

 exudates that the proportion of albumin, euglobulin, and pseudo- 

 globulin is always lower in hydrothorax than in pleurisy. Of dif- 

 ferent forms of ascites, the largest proportion of globuhn and the 

 smallest of albumin occur in cirrhosis; while with carcinoma the pro- 

 portions are reversed. In general the albumin is more abundant than 

 the globulin, ^^ but, as Umber*^^ has found, the proportion of albumin 

 sinks more rapidly in cachexia than does the globulin, corresponding 

 to the similar changes in the blood proteins. The amount of protein 

 lost in exudates is strikingly shown by one of Umber's cases of can- 

 cerous ascites; during one year the fluid removed by paracentesis 

 contained not less than three kilos of pure protein, the patient weigh- 

 ing but 55.5 kilos. 



Several authors have found in inflammatory ascitic exudates a 

 protein having physical and chemical properties much resembhng 



" Meyer and His (Deut. Arch. klin. Med., 1905 (85), 149) claim that the knv- 

 ering of the freezing-point is less than that of the blood in exudates while form- 

 ing, the same as the blood while stationary, and greater during absorption, which 

 they consider indicates a "vital process" on the part of the cells. 



"See also v. Jaksch, Zeit. klin. Med., 1893 (23), 225; Kzentkowski (loc. cit.) " 



■>* Zeit. exp Path., 1910 (8), 22G. 



■'^ Pfiiiger's Arch., 1903 (93), 558. 



"i See Epstein, Jour. Exp. Med., 1914 (20), 334. 



