DROPSY OF THE PERITONEUM ASCITES. 651 



by this may increase the dyspnoea. Still more frequently the secretion 

 of urine is diminished by the pressure of the fluid on the kidneys. It 

 is an old belief that, after diuretics have lost their effect, they reacquire 

 it after tapping the abdomen. This supposition apparently depends 

 on a false interpretation of the fact that ascites adds a new difficulty 

 to an already existing obstruction to the urinary secretion, and when 

 it is removed the obstruction is diminished. The pressure on the vena 

 cava and the iliac veins, where there is much effusion, causes obstruc- 

 tion of the circulation in the lower extremities, external genitals, and 

 the abdominal walls. This explains the venous dilatation of those 

 parts, and the dropsy of the subcutaneous tissue, which may become 

 very great, and lead to mistaken ideas of the disease. We should 

 never neglect to ask whether the legs and scrotum, or the abdomen, be- 

 gan to swell first. 



Almost all patients with ascites are in great danger ; most of 

 them, however, do not die of the ascites, but of the original disease. 

 The obstruction of the respiration or the excoriations and super- 

 ficial gangrenes, which occasionally result from the excessive ten- 

 sion of the skin of the external genitals and thighs, may hasten the 

 fatal result. 



Physical examination of the abdomen is most important in the 

 diagnosis of ascites. On inspection, the first thing noticed is the dis- 

 tention and peculiar form of the abdomen. As long as the effu- 

 sion is moderate, the shape of the belly changes with every change of 

 position of the body. If we examine the patient while he is standing, 

 the lower part of the abdomen appears prominent; if he be lying 

 down, the belly appears very broad. But if the transudation be ex- 

 cessive, the abdomen is protruded everywhere as far as the lower ribs ; 

 the false ribs themselves are elevated and pressed outwardly. Then 

 the abdomen maintains its shape in all positions. In excessive ascites, 

 inspection almost always shows thick networks of blue veins in the 

 thinned coverings of the abdomen. The navel is protruded, and rup- 

 tures in the tissue of the corium form bluish-white translucent striae, 

 which also occur during pregnancy, if the abdomen be very much dis- 

 tended. If the level of the fluid rise above the brim of the pelvis, we 

 may feel fluctuation by placing one hand flat on the abdomen and 

 smartly tapping on the opposite side with the fingers of the other 

 hand. Lastly, wherever the fluid is in contact with the abdominal 

 wall, percussion is absolutely dull. At the same time it is important 

 to notice that, except in those cases where the whole anterior surface 

 gives a dull percussion-sound, the dulness varies with any change in 

 position of the patient, because the fluid always goes to the most de- 

 pendent part. 



