4 - Peritoneum and Upper Abdominal

What is the Falciform Ligament?

A double layer of peritoneum that divides the liver into Right and Left lobes. It anchors the liver to the diaphragm above and anterior body wall. At its base, we find the round ligament of the liver (aka obliterated umbilical vein).

Where does the abdominal aorta begin?

At the aortic hiatus in the diaphragm at T12 level and ends at L4 splitting into the R & L common iliac aa. this bifurcation is ~ 2 to 3 cm inferior and to the L of the umbilicus ~ level of the iliac crests.

Describe the anatomy and connections of the Gallbladder. Function?

Attached to inferior surface of the liver - fundus (can see when body is in anatomical position), body and neck. Contacts duodenum, colon, and anterior abdominal wall. Receives bile produced by liver via bile ducts. Bile then drains into duodenum through ducts.

The Lesser Omentum extends between the _______ and the ________.

Between the stomach and the liver.

Where is the hepatorenal pouch/Pouch of Morrison?

Bounded by the liver, right kidney, colon, and duodenum. It is the lowest part of peritoneal cavity when recumbent. Fluids may move from here down into rectovesical/uterine when reclining or sitting up.

First major branch off abdominal aorta? Supplies what? Names of branches?

Celiac Trunk Supplies liver, gb, esophagus, stomach, pancreas & spleen 3 main branches -Common hepatic a. -L. gastric a. -Splenic a.

Anatomy, position, of pancreas

Consists of a head, neck, body, tail and uncinate process. Retroperitoneal & transverse across posterior abdominal wall. Surrounded by C-shaped duodenum on R & spleen on L

What organs does the liver touch?

Contacts the Gallbladder, stomach, duodenum, colon & Right kidney

What are the surfaces of the liver? What lobes and ligaments are associated with each surface?

Diaphragmatic Liver - Coronary ligament over the right lobe anteriorly - Over the left lobe is the left triangular ligament - Round ligament at the inferior margin of the falciform ligament Visceral Liver & Porta Hepatis (posterior view) - Caudate (superiorly) and Quadrate (inferiorly) lobes - Several depressions from adjacent viscera and structures. Each is named for the associated viscera.

Describe the surfaces and function of the spleen.

Diaphragmatic surface: contacts diaphragm along ribs 9-11 Visceral surface: Contacts with stomach, kidneys, and colon and each create impressions (see photo) Lymphatic organ (red and white pulp) Functions: store RBCs; filter & remove old RBCs; store monocytes

Why is the common bile duct important?

Embryological delineation: At the point where the pancreatic duct & common bile duct join and enter the major duodenal papilla, every superior is consider foregut & everything inferior is midgut

Describe the drainage of the Pancreatic Ducts

Enzymes drain from pancreas via 1 or 2 ducts - Main pancreatic duct: enters duodenum with bile duct at major duodenal papilla - Accessory pancreatic duct: may enter duodenum as well. About 2 cm superior to major papilla. Pattern of pancreatic drainage is variable

Where does the Greater Omentum attach? Associated ligament(s) and the ligamental composition? Its function?

From the greater curvature stomach to the transverse colon (like an apron over the small intestines). A portion is the Gastrocolic Ligament made of 4 layers of peritoneum. It serves to wall off infection, but can create adhesions with chronic inflammation.

Where does the Lesser Omentum attach? Associated ligament(s) and the ligamental composition?

From the lesser curvature of the stomach and the duodenum (and also the liver) superficial to the Omental Bursa. 2 portions connect these structures 1. Hepatogastric ligament: connects liver to stomach 2. Hepatoduodenal ligament: Connects liver to duodenum and contains the portal triad

Describe the organization of mesentery from a lateral cross-sectional view.

Greater sac is the most superficial layer on the anterior (green) aka Supracolic and also majority of lower posterior portion of mesentery (red) aka Infracolic. The Greater Omentum lies just deep to the Supracolic Greater Sac from the greater curvature of the stomach to the transverse colon and down across the intestines. The Lesser Sac/Omental Bursa (black) posterior to stomach and inferior to the liver and extends to greater omentum. Superiorly, bounded by hepatogastric ligament. The Transverse Mesocolon (blue) is attached to the transverse colon and greater curvature of the stomach and also posterior wall.

What are the peritoneal pouches and when are they visible?

Hepatorenal and rectovesical/rectouterine pouches. Visible possibly when standing or when lying down for too long (pathological fluids can accumulate in these recesses).

Branches off & location of gastroduodenal artery?

Inferior br. of common hepatic a. which runs toward junction of stomach & duodenum. - Sends Supr. pancreaticoduodenal aa. to pancreas/duodenum - Sends R gastroepiploic a. (R gastro-omental a.) to greater curvature of stomach

What is the function of the mesentery proper? Location? What anchors the mesentery proper?

It anchors most of the small intestine to the posterior abdominal wall. Runs diagonally from duodenojejunal junction to ileocecal junction (a distance of 15 to 20 cm in adults). The Suspensory ligament of Treitz anchors it.

Location, supply to, and Branches off Splenic Artery

Left br. of celiac trunk that runs toward spleen & supplies pancreas & spleen. - Sends short gastric aa. which supply lesser curvature of stomach & L gastroepiploic a. (L gastro-omental a.) which supplies greater curvature of stomach

Name the infraumbilical peritoneal folds

Median umbilical fold - Urinary bladder to umbilicus - Median umbilical ligament (fetal urachus) (2) Medial umbilical folds - Medial umbilical ligaments - Occluded portions of umbilical aa. (2) Lateral umbilical folds - Inferior epigastric vessels

Do the hepatic arteries always arise from the same vessel?

No, variations occur about 40% of the time. Cystic arteries and right gastric arteries also have a lot of variation.

Define retropeitoneal

Organs behind the peritoneum

What is peritoneum and what are the different types and their associated structures?

Peritoneum is a thin, translucent, serous membrane (mesothelium). The parietal peritoneum lines the inner abdominal. The visceral peritoneum covers the organs and is continuous as it wraps around the body wall. It comes up against itself to form a mesentery.

What are the bile ducts?

R & L hepatic ducts: Receives bile from R & L lobes of liver. Common hepatic duct: Receives R & L hepatic ducts Cystic duct: Connected to gallbladder Common bile duct: Receives cystic and common hepatic ducts, joins main empties into duodenum through major duodenal papilla

What are the lobes of the liver?

R, L, Quadrate & Caudate lobes

Where are the rectouterine & vesicouterine pouches in females?

Rectouterine pouch - Posterior space between rectum and the uterus Vesicouterine pouch - Anterior space between bladder and uterus Fluids can move up to hepatorenal pouch if filled/or in Trendelenburg position.

What are the Coronary Ligaments?

Reflections of the peritoneum around the bare area of the liver (upper posterior liver that doesn't have any peritoneum) that attach the liver to the inferior surface of the diaphragm. 2 ligaments - anterior and posterior

What are the branches off the common hepatic a.?

Runs toward liver & gallbladder 2 terminal branches: • Proper hepatic a. • Gastroduodenal a.

Where is the rectovesical pouch in males?

Space between rectum and bladder. Where folds of peritoneum comes down rectum and then back up to bladder. Fluids can move up to hepatorenal pouch if filled/ or in Trendelenburg position.

Location, Supply to, and Branches off Left Gastric Artery?

Superior br. of celiac trunk that runs L toward lesser curvature of stomach. Supplies stomach & esophagus (via esophageal brs.)

Branches off & location of common hepatic artery?

Superior branch of common hepatic a. Runs toward liver & medial to bile duct Right Gastric a. Splits into R & L hepatic aa

What is the opening of the omental bursa? Where is it found?

The omental bursa is accessed through the omental foramen. It is the space behind the lesser omentum.

What can happen to the peritoneal cavity due to disease, injury, or infection?

The potential space can become an actual space filled with liters of fluid (ascites) such as blood, bile, pus, or feces.

Is all of the small intestine anchored to the body wall? If yes, what part(s) are anchored where and via what ligament(s)?

The retroperitoneal duodenum and its vasculature are anchored via the Suspensory ligament of Treitz -- a fibromuscular ligament that crosses over the left crus of the diaphragm to attach to the distal duodenum. (Note how close the vena cava vessels are to this structure) The rest of the small intestine (jejunum and ileum) are intraperitoneal and much more mobile.

The splenorenal ligament extends the ______ and the ________.

The spleen and the kidney. This is where vessels travel to these structures.

What is the splenic hilum?

The splenic hilum is the entry point for the splenic vessels and occasionally the tail of the pancreas reaches this area.

The Gastrosplenic ligament extends between the _______ and the ________.

The stomach and the spleen

What parts of the colon are anchored? How? What are they anchored to (posterior/anterior body wall)?

The transverse mesocolon attaches to anterior portion of the transverse colon and to the greater curvature of the stomach which anchors it to the posterior wall. The ascending and descending colon have no mesentery. The sigmoid colon is anchored to the sigmoid mesocolon to post. body wall. Rectum is partially covered with rectal mesocolon peritoneum.

What creates the peritoneal sac? The peritoneal cavity?

The visceral and parietal peritoneal membranes. The peritoneal cavity is a potential space within the sac. Contains a small amount of serous fluid and allows organs to move freely without friction.

_______ travels between the peritoneal layers

Vessels