[Role of the lymphatics of the diaphragm in the absorption of intraperitoneal liquids].

The diaphragm is the major site of the lymphatic absorption of the intra peritoneal liquids. Known since the middle of the last century, this lymphatic network is at present studied under transmission electron microscopy. The stomata which are intercellular sluices between adjacent mesothelial cells, are the entry of the diaphragmatic network. These stomata open into the lacunae which are dilatations the diaphragmatic subserous lymphatic network. The architecture of these structures explains their one-way character from the abdomen to the thorax and the role of the respiratory movements. This network collects the fluids into the trans diaphragmatic lymphatics. Pleural effusion appears when the quantity of liquids in the diaphragmatic lymphatic network exceeds the capacities of drainage of the lymphatic efferents, thus explaining the reactional pleural effusion caused by underdiaphragmatic inflammatory processes.