The peritoneal cavity is a

potential space In anatomy, a potential space is a space between two adjacent structures that are normally pressed together (directly apposed). Many anatomic spaces are potential spaces, which means that they are potential rather than realized (with their realiz ...

located between the two layers of the

peritoneum The peritoneum is the serous membrane forming the lining of the abdominal cavity or coelom in amniotes and some invertebrates, such as annelids. It covers most of the intra-abdominal (or coelomic) organs, and is composed of a layer of mesotheli ...

—the parietal peritoneum, the

serous membrane The serous membrane (or serosa) is a smooth epithelial membrane of mesothelium lining the contents and inner walls of body cavity, body cavities, which secrete serous fluid to allow lubricated sliding (motion), sliding movements between opposing ...

that lines the

abdominal wall In anatomy, the abdominal wall represents the boundaries of the abdominal cavity. The abdominal wall is split into the anterolateral and posterior walls. There is a common set of layers covering and forming all the walls: the deepest being the vi ...

, and visceral peritoneum, which surrounds the internal organs. While situated within the

abdominal cavity The abdominal cavity is a large body cavity in humans and many other animals that contain Organ (anatomy), organs. It is a part of the abdominopelvic cavity. It is located below the thoracic cavity, and above the pelvic cavity. Its dome-shaped roo ...

, the term ''peritoneal cavity'' specifically refers to the potential space enclosed by these peritoneal membranes. The cavity contains a thin layer of lubricating

serous fluid In physiology, serous fluid or serosal fluid (originating from the Medieval Latin word ''serosus'', from Latin ''serum'') is any of various body fluids resembling serum, that are typically pale yellow or transparent and of a benign nature. The fl ...

that enables the organs to move smoothly against each other, facilitating the movement and expansion of internal organs during digestion. The parietal and visceral peritonea are named according to their location and function. The peritoneal cavity, derived from the coelomic cavity in the

embryo An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sp ...

, is one of several body cavities, including the pleural cavities surrounding the lungs and the pericardial cavity around the heart. The peritoneal cavity is the largest serosal sac and fluid-filled cavity in the body, it secretes approximately of fluid daily. This fluid serves as a lubricant and has

anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation, fever or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs reduce pain by inhibiting mechan ...

properties. The cavity is divided into the greater and lesser sacs, with the greater sac further subdivided into the supracolic and infracolic compartments.

Compartments

The peritoneal cavity is divided into the greater and lesser sacs. The greater sac comprises the majority of the peritoneal cavity, while the lesser sac, also known as the omental bursa, is smaller and situated posterior to the stomach and

lesser omentum The lesser omentum (small omentum or gastrohepatic omentum) is the double layer of peritoneum that extends from the liver to the lesser curvature of the stomach, and to the first part of the duodenum. The lesser omentum is usually divided into t ...

. They are connected by the

omental foramen In human anatomy, the omental foramen (epiploic foramen, foramen of Winslow after the anatomist Jacob B. Winslow, or uncommonly aditus; ) is the passage of communication, or foramen, between the greater sac, and the lesser sac of the peritoneal ...

. The greater sac is further subdivided into two compartments by the mesentery of the

transverse colon In human anatomy, the transverse colon is the longest and most movable part of the Large intestine#Structure, colon. Anatomical position It crosses the abdomen from the ascending colon at the right colic flexure (hepatic flexure) with a downward ...

, known as the transverse mesocolon. This division creates an upper and a lower compartment within the greater sac, named the supracolic and infracolic compartment respectively, each housing different organs and structures of the abdominal cavity. The

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

spleen The spleen (, from Ancient Greek '' σπλήν'', splḗn) is an organ (biology), organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The spleen plays important roles in reg ...

, stomach, and lesser omentum are contained within the supracolic compartment. The

small intestine The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...

surrounded by the ascending, transverse, and

descending colon In the anatomy of humans and homologous primates, the descending colon is the part of the colon extending from the left colic flexure to the level of the iliac crest (whereupon it transitions into the sigmoid colon). The function of the descen ...

, and the paracolic gutters are contained within the infracolic compartment.

Clinical significance

The peritoneal cavity is widely used in intraperitoneal injections to administer chemotherapy drugs, and is also utilized in

peritoneal dialysis Peritoneal dialysis (PD) is a type of kidney dialysis, dialysis that uses the peritoneum in a person's abdomen as the membrane through which fluid and dissolved substances are exchanged with the blood. It is used to remove excess fluid, correct e ...

. An increase in capillary pressure in the abdominal organs can cause fluid to leave the

interstitial space An interstitial space is an intermediate space located between regular-use floors, commonly located in Hospital, hospitals and laboratory-type buildings to allow space for the mechanical systems of the building. By providing this space, laborator ...

and enter the peritoneal cavity, resulting in a condition called

ascites Ascites (; , meaning "bag" or "sac") is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdo ...

. When

cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless Extracellular fluid#Transcellular fluid, transcellular body fluid found within the meninges, meningeal tissue that surrounds the vertebrate brain and spinal cord, and in the ventricular system, ven ...

overaccumulates, such as in

hydrocephalus Hydrocephalus is a condition in which cerebrospinal fluid (CSF) builds up within the brain, which can cause pressure to increase in the skull. Symptoms may vary according to age. Headaches and double vision are common. Elderly adults with n ...

, the fluid is commonly diverted intentionally to the peritoneal cavity using a surgically placed cerebral shunt. Sampling of body fluid from the peritoneal cavity is referred to as peritoneocentesis.

References

External links

* {{Authority control Abdomen

Compartments

Clinical significance

See also

References

External links