2/6 The Earlier Theories of Edema [Dec. 



could be thus administered without a fatal result, anasarca never 

 ensued. However, some of the organs were edematous and in a 

 few dogs ascites was present. The organs showing edema in 

 nephritic conditions were never so affected by injected salt. Be- 

 cause they were able to produce anasarca in dogs by subjecting the 

 part to irritants before the salt Solutions were injected, Cohnheim 

 and Lichtheim concluded that an alteration of the vessel walls was 

 necessary for the passage of fluid. These investigations disproved 

 Bright's theory. 



Gaertner (1891) repeated the experiments of Cohnheim and 

 Lichtheim but frequently obtained different results. He observed 

 extensive edema of the skin and underlying tissue, and claimed 

 that the results published by Cohnheim and Lichtheim were due 

 to a too rapid injection of the salt Solution. Gaertner, with 

 Bartels, Stewart, and Garinger, maintained that the principal cause 

 of edema lay in an excessive amount of water in the System. 



Fleischer, repeating the experiments of Cohnheim and Licht- 

 heim, injected salt Solution after ligating the Ureters and found 

 neither increase in the blood pressure nor production of edema of 

 the skin. Francotte (1888) in similar experiments, found that 

 edema of the skin followed such injections. 



Lassar (1877) observed that the amount of lymph coming from 

 a lymph vessel of an inflamed extremity was greater than normal. 

 Emminghaus (1874) found this to be the case, also, in obstruction 

 edema, but there was a great deal of difference between the physical 

 and chemical properties of fluids drawn from a leg which was 

 inflamed and from one in which stasis existed. These facts indicate 

 that conditions which change the permeability of the vessel walls 

 have much to do with the causation of edema. 



Welch (1878) made an extended study of the production of 

 edema of the lungs by ligating the arch of the aorta and the left sub- 

 clavian artery. When he tried to produce edema of the lung by 

 venous obstruction it was necessary to ligate all the veins of the left 

 lung and those of the Upper lobe of the right lung. He concluded 

 that an explanation of edema of the lungs upon the basis of active 

 and passive hyperemia was insufficient. In other experiments he 

 produced edema of the lungs by digital compression of the left 



