CHAPTER XIII. 

 DISEASES OF THE PERITONEUM. 



General Remarks. — The peritoneum is a serous sac, and, 

 considering all of its reflections and fossae, it covers a surface 

 very nearly as great as that of the skin. In the female it 

 differs from other serous cavities in that it has an indirect 

 external opening through the uterine tube; in the male there 

 is no opening. 



The peritoneum through the lymphatics and bloodvessels 

 has great power of absorption as has been demonstrated on 

 numerous occasions. The dog or rabbit will absorb fluid 

 equal to 10 per cent, of the body weight in a half hour. 

 Fluids and soluble substances are readily taken up and car- 

 ried away by the blood, while insoluble substances, including 

 microorganisms, are taken up by the lymphatics with the 

 aid of the phagocytes. In health, the secretion of fluid into 

 the peritoneal cavity and the absorption therefrom is just 

 sufficient to keep the surfaces moist and free from infection. 

 In disease this normal equilibrium becomes disturbed, and 

 either produces a dry condition of the membrane, from 

 absorption being greater than secretion (acute inflammation), 

 or secretion being in excess of absorption (ascites). The 

 presence of the fluid in the peritoneal sac has a further action 

 than preventing friction to the surface, and that is by exert- 

 ing a bactericidal action. 



The lymphatic absorption is carried forward by the 

 lymphatic trunks to the mediastinal glands. Experiments 

 have shown that microorganisms can be removed from the 

 peritoneal sac via the lymph stream, and carried into the 

 mediastinal glands in six minutes after their injection into 

 the abdominal cavity. The peritoneum covering the dia- 

 phragm and the omentum is most active in this process of 



