Ascites is the pathologic accumulation of fluid in the abdominal cavity. Normally, there is a balance between fluid secretion and absorption in the peritoneal cavity. Ascites occurs when either the secretion rate increases or the absorption rate decreases isproportionate to the other. A variety of benign and malignant conditions could lead to the development of ascites.

Cytoreductive surgery is an extensive, lengthy procedure that lasts several hours. Frequently, it is necessary to remove segments of small and large bowel, spleen, stomach and pancreas, to achieve adequate cytoreduction. The extent of resection will depend upon the location and size of the tumor. The long-term results are directly related to the ability of the surgeon in the removal of all visible tumor and to the size of the deposits of residual disease. The smaller the size of the residual tumor deposits the greater the chance the tumor will respond to chemotherapy.

The term hyperthermia refers to raising the temperature of a part of the body above normal for a defined period of time.

Hyperthermic Intraoperative Intraperitoneal Chemotherapy
Hyperthermic Intraoperative Intraperitoneal Chemotherapy refers to the intraoperative administration of heated chemotherapy into the peritoneal cavity, at the time extensive removal of tumor has been completed (Cytorective surgery). This technique permits the administration of high concentrations of selected drugs into the abdominal and pelvic surfaces. The drug makes contact with all the peritoneal surfaces of the tumour resected areas.

Peritoneum is the smooth transparent serous membrane which lines the cavity of the abdomen, or the whole body cavity when there is no diaphragm, and, turning back, surrounds the viscera, forming a closed, or nearly closed, sac. The peritoneum provides a frictionless surface over which the abdominal viscera can freely move, and the mesothelial lining secretes fluid that serves to lubricate the peritoneal surfaces.

Peritoneal fluid
Normally, approximately 100 ml. of clear straw-coloured fluid is present in the peritoneal cavity of the adult. This fluid contains water, electrolytes and other solutes derived from the interstitial fluid of the neighbouring tissue and from the plasma of adjacent blood vessels. It also contains proteins and a variety of cell types. The latter vary in their numbers, structure and type in different pathological conditions; hence, they are of diagnostic importance.

Cells in the peritoneal fluid
Normally, the cells in the peritoneal fluid consist of desquamated flat mesothelial elements derived from the peritoneal surfaces, and of wandering macrophages, mast cells, fibroblast, lymphocytes and a small number of other leucocytes. Some of these cells, particularly the macrophages, can migrate freely between the peritoneal cavity and the surrounding connective tissue. The lymphocytes in the fluid provide both cellular and humoral, immunological defence mechanisms.

Peritoneal Absorption:
Substances in complete solution are probably absorbed directly into the blood capillaries, whereas particulate matter in suspension probably passes into the lymph vessels, with the aid of phagocytes. The absorption of fluid is more or less equally rapid in all parts of the peritoneum. The greater absorption in the upper part of the abdomen is due to the larger area of the peritoneal surface in the subphrenic region and absorption is expedited by the respiratory movements in this region.

Peritoneal cavity
The peritoneal cavity is the potential space containing the abdominal and pelvic viscera.

Peritoneal carcinomatosis
Peritoneal carcinosis refers to a wide variety of tumors that present with extensive peritoneal involvement with or without parenchymal involvement of solid organs such as the liver, spleen and lymph nodes. It is a common evolution of cancers of the digestive tract such as stomach, small bowel, colon, rectum, appendix and pancreas. Other tumors that may lead to these conditions include: ovarian, mesothelioma, Pseudomyxoma peritonei and sarcomas.

Intraperitoneal chemotherapy:
Treatment in which anticancer drugs are put directly into the abdomen through a thin tube.