COMPOSITION OF EDEMATOUS FLUIDS 297 



proteids even less than 0.1 per cent. (Hoffmann * ). An increase 

 in solids occurs after the effusion has existed for some time, 

 presumably because of absorption of water and salts, leaving a 

 slowly increasing proportion of proteids. Furthermore, the 

 composition of the patient's blood has considerable influence on 

 the composition of the effusion ; this is particularly true in the 

 case of ascites from portal obstruction, the contents of the blood 

 coming from the intestine during digestion modifying the 

 composition of the ascitic fluid. Thus Miiller, 2 in a case of 

 portal vein thrombosis, found in the ascitic fluid of a patient on 

 an ordinary mixed diet, 0.179 per cent, nitrogen ; on a proteid- 

 rich diet, 0.2494 per cent. N ; on a proteid-poor diet, 0.1764 

 per cent. N. In cachectic conditions the proportion of proteids 

 is less than in stronger individuals, and, as in the blood plasma, 

 the albumin decreases more rapidly than the globulin as the 

 cachexia advances (Umber 3 ). 



Physical Chemistry of Bdematous Fluids. The 

 differences between transudates and exudates depends almost 

 solely on their proteid contents, for the non-proteid elements 

 are almost identical with normal lymph and blood-serum, which 

 naturally must be so since any original or temporary deviation 

 in osmotic pressure must be rapidly equalized by diffusion. 

 Thus Bodon 4 finds the concentration of the electrolytes nearly 

 constant in spite of considerable differences in composition of 

 various edema fluids, indicating that the serosa permits passage 

 of inorganic salts always in the same concentration, while hold- 

 ing back the organic substances. Rzentkowski 5 found some 

 slight differences in molecular concentration as indicated by the 

 freezing-point ; in tuberculous pleurisy the average lowering 

 was 0.523, that of the serum being 0.56 ; in cardiac dropsy 

 the subcutaneous fluid gave 0.548, and in renal dropsy 

 0.583; tuberculous peritonitis, 0.523; cirrhosis 0.536; 

 carcinomatous edema 0.547. Of these figures, the most sig- 

 nificant is the comparatively high molecular concentration of the 

 fluid in nephritis, supporting the contention that the cause of renal 

 edema is retention of crystalloids. 6 Tieken 7 has found the fol- 

 lowing results in transudates, exudates, and other body fluids : 



1 Deut. Arch. klin. Med., 1889 (44), 313. 



2 Deut. Arch. klin. Med., 1903 (76), 563. 

 8 Zeit. klin. Med., 1903 (48), 364. 



4 Pfluger's Arch., 1904 (104), 519; also see Galeotti, Lo Sperimentale, 1901 

 (55), 425. 



5 Loc. tit, and also Berl. klin. Woch., 1904 (41), 227. 



6 Purulent exudates may show a high molecular concentration ( - 0.84 in one 

 case), due to decomposition of the proteids into crystalloids (Kzentkowski). 



7 Amer. Medicine, 1905 (10), 822. 



