EDEMA EFFUSION 229 



Disease of the external genital organs and lower end of vagina will affect the 

 inguinal glands along the inguinal ligament. 



Disease of the neck of the womb (cervix uteri) will affect iliac glands, 

 while disease of the body of the womb (fundus uteri), or of ovaries or tubes, 

 will affect lumbar glands. 



The transmission of the causes of disease from one organ to another by the 

 lymphatics is called metastasis; it is often seen to follow a malignant growth. 



The lymph itself, as we have seen, is the medium between the 

 blood and the tissues. It is only through the lymph that the blood 

 can feed the tissues and receive the products of their metabolism. 

 The thinness of the capillary wall allows this interchange between 

 blood plasma and the lymph in the spaces around the vessels. 

 The one place of exception is in the lungs. There, oxygen from 

 the air passes directly into the capillary blood and Co 2 from the 

 blood, directly into the air of the lungs. 



The process of osmosis has already been mentioned, in con- 

 nection with food absorption and in considering the physiology 

 of the blood (pages 170 and 214). It is by the forces included 

 under this name that the nutritive substances circulating in the 

 blood are delivered to the tissues and wastes are at the same 

 time removed from them. 



Clinical notes. Edema is an accumulation of lymph in the tissue spaces. 

 We have seen that an interchange between the blood and lymph capillaries is 

 continually going on, the blood providing lymph, the tissues receiving it, 

 abstracting nutriment and adding waste. This is not all returned to the 

 capillaries, a portion is left in the spaces to be carried by lymph vessels to 

 the two lymph ducts which convey it to certain large veins. 



Should this balance of interchange be disturbed, the effect is evident at 

 once. Whether the supply be too abundant or the outflow be obstructed 

 the same result would follow the tissues would be overwhelmed with 

 fluid, causing edema. 



Inflammation of serous membranes, if severe, results in the accumulation 

 of lymph or serum in their cavities this is an effusion. 



Inflammation in the tissues themselves causes a local excess of lymph 

 derived from the increased quantity of blood or hyperemia, induced by local 

 irritation. The accumulation of excess lymph constitutes induration or 

 hardening. 



Hyperemia is evident to the eye when near the surface, by 

 the redness and heat which it causes. The vessels become so 

 crowded with cells that the blood can move with difficulty. Serum 

 and corpuscles make their way through the vessel walls and fill 



