The peritoneum is a thin,continuous,andglistening serous membrane that lines the abdominal and pelvic cavities and clothes the visceras.

It consists of two continuous layers Parietal peritoneum:lines the abdominopelvic

wall Visceral peritoneum:investing the visceras

PERITONEAL CAVITY

The potential space b/w the visceral and parietal peritoneum is called the peritoneal cavity.In males this is a closed space,but in females there is communication with the exterior through uterine tubes,uterus and vagina.

The peritoneal cavity is the largest cavity divided into 2 parts

Greater sac:extends from diaphragm down into the pelvis

Lesser sac:lies behind the stomach. These sacs are in free communication

through an oval window called epiploicforamen, foramen of winslow.

Anteriorly:portal vein,hepatic artery,and bile duct

Posteriorly:IVC,right crus of diaphragm Superiorly:caudate lobe of liver Inferiorly:ist part of duodenum

Intraperitoneal organs: totally covered with visceral peritoneum.e.gstomach,jejunum,ileum,spleen,transversepart of colon .

Retroperitoneal organs: lies behind the peritoneum and partially coverd by visceral peritoneum.e.g pancreas,ascending and descending parts of the colon and kidneys.

In reality no organ is within the the peritoneal cavity.

DESCRIPTIVE TERMS FOR PERITONEUM

MESENTERY: Double layer of peritoneum connecting the organs to the posterior abdominal walle.g mesentery of small intestine,transverse and sigmoid mesocolon

OMENTUMA double layered fold of peritoneum that passes from the stomach and the proximal part of duodenum to the adjacent organs in the abdominal cavity.Lesser omentum: connects the lesser curvature of stomach and proximal part of duodenm to the liver.Greater omentum: is a prominent fold that hangs from the greater curvature of the stomach and duodenum and folds back and attaches to the anterior surface of the transverse colon.

PERITONEAL LIGAMENTS

Double layer of peritoneum that connects an organ with another organ or to the abdominal wall.LIVER: is connected to the Anterior Abdominal wall by falciform ligament,To the Stomach by the hepatogastric ligament,And to the duodenum by the hepatoduodenal ligament.

CONTD…

STOMACH: is connected to theInferior surface of the diaphragm by the gastrophrenicligament Spleen by the gastrosplenicligamentTransverse colon by the gastrocolic ligament

PERITONEAL FOLDS

A reflection of peritoneum that is raised from the abdominal wall by underlying structures.e.gMedian umbilical fold:median umbilical ligamentTwo medial umbilical folds:medial umbilical ligamentsTwo lateral umbilical folds:inf.epigastricvessels

Peritoneal Recess

A pouch of peritoneum that is formed by a peritoneal fold.e.gInferior recess of omental bursaSupravesical and medial and lateral inguinal fossaeb/w the umbilical folds

COMPARTMENTS

The transverse mesocolon divides the abdominal cavity into:Supracoliccompartment containing stomachInfracoliccompartment containing small intestine ,ascending and descending colon

CONTD…

The infracoliccompartment lies posterior to greater omentum and is divided into right and left infracolicspaces by mesentery of small intestine.Free comunicationoccurs b/w these compartments through paracolicgutters

CLINICAL CONSIDERATIONS

ASCITES:Excessive accumulation of the peritoneal fluid within the peritoneal cavity.Causes:hepaticcirrhosis,malignantdisease,congestive heart failure.Symptoms:shortness of breath,abdominalpain,bloatingTests:paracentesis(abdominaltap)Treatment:diuretics.antibiotics.

PERITONEAL PAIN

FROM THE PARIETAL PERITONEUM:Parietal peritoneum linning the anterior abdominal wall is supplies by T6-T12 and L1 spinal nerves. Abdominal pain is therfore of somatic type and can be localized.

FROM THE VISCERAL PERITONEUM:The visceral peritoneum including the mesenteries is innervated by autonomic afferent nerves.Stretch caused by overdistention of viscus,or pulling on a mesentery give rise to sensation of pain.painarising from an abdominal viscus is poorly localized.