The peritoneum is a thin skin, also called the peritoneum, in the abdomen and at the beginning of the pelvis. It is raised in folds and covers the internal organs. The peritoneum serves to supply the organs and produces a viscous fluid that reduces frictional resistance when the organs move.
What is the peritoneum?
The peritoneum protects the area of the body downward from the ribs into the pelvis. This section of the body contains most of the human organs, most of which are covered by the peritoneum. They are held in position by the peritoneum without becoming completely immobile. This function is particularly important in the intestinal tract with its tightly laid loops of intestine. Overall, the peritoneum is permeated by a number of blood vessels, lymphatic vessels and nerves that supply the organs. Movements in the abdomen are facilitated by the peritoneum through its ability to produce a secretion that increases the lubricity of the organs during these positional changes. Because of its folded structure, the peritoneum can reach a total size of up to two square meters.
Anatomy and structure
Divided, the peritoneum is composed of two sheets. The parietal sheet covers the abdominal wall from the inside. The visceral sheet, on the other hand, covers the parts of the abdominal organs. There are five longitudinal folds in the peritoneum on the anterior abdominal wall. Within the abdominal cavity, a number of peritoneal pockets are also formed. The peritoneum produces a small amount of secretion. The average amount of peritoneal fluid present is between 50ml and 70ml. This amount is sufficient for the organs to glide within the peritoneum. The nerve supply of the parietal leaflet is very sensitive. It is also sensitive to impairments of the abdominal wall. Much less pronounced is the sensitivity of the peritoneum within the abdominal cavity around the organs.
Functions and tasks
The peritoneum performs a specific protective function for all organs located within its sheets. Its function is divided into two major areas. Below the rib cage, the body area is largely unprotected from other structures. Although the muscles provide stability, they are not a system specifically designed to protect the organs as is the peritoneum. Especially in the area of the lower digestive organs, it is important that the long structures of the digestive tract remain fixed in the delicate sling position. In another role, the peritoneum increased the limited but necessary mobility of the organs against each other with the production of peritoneal fluid. During body movements, the organs in the abdominal cavity are exposed to slight changes in position at any time. Due to the viscous serum, the organs slide past each other and can resume their original position just as easily. The peritoneum fulfills this dual function through the layer of tissue that produces the serum, under which there is still a layer of stabilizing connective tissue. Only a few organs, such as the rectum and female uterus, lie completely outside the peritoneum. A number of organs positioned behind the abdominal wall, such as the kidneys and pancreas, are located behind the peritoneum in such a way that at least part of their surfaces are covered by the peritoneum.
Diseases
Because of the large surface area of the peritoneum, metastases often form in its area when cancer of the internal organs occurs. A rare type of cancer is one that arises primarily in the peritoneal area called mesothelioma. Internal diseases of very different causes lead to increased production and accumulation of fluid. The abdominal swelling can be significant and is referred to as ascites. In many cases, this abdominal dropsy is a clear first indication of an underlying disease of the liver, heart disease or tumor involvement. Injuries to the abdominal wall cause peritonitis. Appendicitis is also a cause of inflammation of the peritoneum, which is accompanied by severe pain. In the majority of cases, peritonitis is a concomitant disease that severely affects physical well-being due to the severe pain and symptoms of inflammation. The increased fluid accumulation must be drained. This requires effective treatment of the underlying disease in addition to the peritoneum.
Typical and common peritoneal diseases
- Peritonitis
