156 FKANKLIN C. McLEAN 



PAET I 



The Clinical Features of Various Forms of Edema 



The General Features of Edema. The recognition of edema is usually 

 not difficult, especially in the subcutaneous tissues, where, as a rule, it 

 first appears. The edema of heart failure, which appears first in the 

 most dependent portions of the body, and the edema of nephritis, which 

 shows a particular predilection for the soft tissues about the orbit, are 

 familiar to every physician. 



The Skin and Subcutaneous Tissues. In the early stages of edema the 

 skin may appear normal, on mere inspection, especially in cases of heart 

 failure during the stage when the edema disappears at night. The first 

 objective sign is usually the characteristic pitting on pressure. If edema 

 is present, when firm pressure is made with the finger tips the depression 

 produced remains after the finger tips are removed, and may be observed 

 by inspection or by passing the fingers lightly over the area. When no 

 edema is present the normal elasticity of the subcutaneous tissues restores 

 the contour of the skin as soon as the finger tips are removed. Ordinarily 

 such pressure over an edematous area causes no pain. 



A slight puffiness about the eyes is frequently the earliest sign of the 

 edema of nephritis. Here the tissues are too soft to elicit pitting on 

 pressure, but the puffiness, often associated with a pasty appearance of 

 the skin, is characteristic. 



After edema has persisted for some time the skin assumes a thin and 

 transparent appearance. As it increases, it becomes smooth and shiny. 

 At first, soft and pitting easily on pressure, the edematous tissues later 

 become hard and indurated. Considerable pressure may then be necessary 

 to cause pitting. This is especially true of edema of heart disease, if the 

 patient has not been confined to bed, but the forms of edema which occur 

 independently of circulatory disturbance are less influenced by posture. 



The edema of heart failure nearly always shows the influence of 

 gravity, in that the more dependent portions of the body are involved first. 

 When there is a considerable amount of fluid in the extremities, accom- 

 panied by marked distentions of the skin, trophic changes may result from 

 the disturbance of nutrition. Blebs and bullse are not uncommon, and 

 occur most frequently on the feet and legs. Occasionally the skin breaks 

 and there is leakage of watery fluid through the fissures. Secondary 

 infection of such lesions may result in changes due to inflammation. 



Inflammation of the skin or subcutaneous tissues often leads to more 

 or less circumscribed areas of edematous swelling about the point of infec- 

 tion. Here the swelling has the characteristics of edema, in combination 

 with those of inflammation. 



