Mesenteries & Abdominal Foregut (Brauer) Flashcards
What is the differences between parietal and visceral peritoneum and what are their functions?
- parietal peritoneum: lines inner surface of abd wall
- visceral peritoneum: covers many of the abd organs
(these layers and continuous w/ each other)
- functions: prod peritoneal fluid that lubricates peritoneum; minimize friction between abd organs; resist infection by prod antibodies, mobilizing leukocytes, and localizing infection
- double layered peritoneal membrane that attaches intraperitoneal organs to the abd wall
- within this structure are located the arteries, veins, nerves, and lymphatics that supply these organs
- variable amnt of fat deposited within this structure
mesentery
- regional mesenteries connecting one organ w/ another organ or connecting an organ to the abd wall
- most are named by the organs they connect
peritoneal ligaments
What are the peritoneal ligaments?
- gastrophrenic
- gastrosplenic
- gastrohepatic (hepatogastric)
- hepatoduodenal
- gastrocolic
- transverse mesocolic
- phrenocolic
- splenorenal (not shown)
- peritoneal ligament connecting liver to stomach and 1st part of duodenum
- 2 parts: hepatoduodenal and hepatogastric ligaments
lesser omentum
- peritoneal ligament attached to greater curve of the stomach, 1st part of the duodenum, and the transverse colon
- elongated so it drapes over the anterior surface of the intestines
- composed of: gastrocolic, gastrophrenic, and gastrosplenic ligaments
greater omentum
- _______ ____ is the space posterior to the stomach, lesser omentum, and greater omentum
- _______ ____ is the space anterior the stomach, lesser omentum, and greater omentum and generally is known as the abdominal cavity
- the epiploic foramen connects these two spaces
- lesser sac (omental bursa) is the space posterior to the stomach, lesser omentum, and greater omentum
- greater sac is the space anterior the stomach, lesser omentum, and greater omentum and generally is known as the abdominal cavity
- the epiploic foramen connects these two spaces
What are the boundaries of the epiploic foramen (opening that connects greater & lesser sacs)?
- anterior: hepatoduodenal ligament
- inferior: 1st part of duodenum
- superior: peritoneal reflection from liver to inferior vena cava
- posterior: peritoneum covering inferior vena cava
Where is the stomach located within the body and what are important landmarks a/w this structure?
-
location: right and left upper quadrants
left: fixed at level of T10-11
right: fixed at level of L1 - parts: cardiac, fundus, body, pylorus, pyloric sphincter
- greater curve: inferior border of stomach, greater omentum attachment
- lesser curve: superior border of stomach, lesser omentum attachment
- esophageal hiatus ((o)esophagus) at level of T10
- esophagus enters stomach at cardiac orifice at level of T11
- cardiac notch separates esophagus from fundus of stomach
- protrusion of part of the stomach into mediastinum through esophageal hiatus of the diaphragm
- sliding: more common type, cardiac and part of fundus through esophageal hiatus, some regurgitation
- para-esophageal type: less common, cardia is nml position, fundus through esophageal hiatus, no regurgitation
hiatal hernia
Where is the spleen located?
- location: left upper quadrant or left hypochondriac region lying parallel to left ribs 9-11 along the mid-axillary line between stomach and diaphragm
- intraperitoneal organ
- attached to gastrosplenic and splenorenal ligaments
Where is the duodenum located and what are the different parts of this structure?
- location: begins at pylorus and ends at duodenojejunal junction (level of L2)
-
4 parts:
1) superior (A and B): intraperitoneal, travels superior and to the right, a/w hepatoduodenal ligament
2) descending (C): retroperitoneal, openings of hepatopancreatic duct (bile duct and pancreatic duct), major and minor duodenal papilla
3) horizontal (D): retroperitoneal, crossed by superior mesenteric artery and vein
4) ascending (E): retroperitoneal, joins w/ jejunum, suspensory ligament at duodenojejunal junction (ligament of Treitz)
What are the intraperitoneal organs?
- liver
- spleen
- stomach
- superior part of the duodenum
- jejunum
- ileum
- transverse colon
- sigmoid colon
- superior part of the rectum
What are the retroperitoneal organs?
- kidney
- adrenal glands
- ureter
- pancreas
- distal duodenum
- ascending/descending colons
(from Dr. Brauer: The first part of the duodenum has both an intraperitoneal and retroperitoneal portion. Just down from the pylorus of the stomach the first 2cm or so of the duodenum has a mesentery and thus is considered intraperitoneal. The next 3-4 cm of the first part of the duodenum is retroperitoneal. The 2nd and 3rd parts of the duodenum are retroperitoneal. The fourth part that ascends is also retroperitoneal. As it transitions into the jejunum (which is intraperitoneal), there may be a short bit of distal 4th part of duodenum that becomes intraperitoneal as it is at this transition point where you find the suspensory ligament of the duodenum)
What is the innervation to the foregut?
- sympathetic: from T5-9; from greater splanchnic nerves entering from thorax, synapse in celiac ganglia and then distributed via vessels
- parasympathetic: from anterior and posterior vagal trunks (CN X), pierce diaphragm at T10, LARP mnemonic; branches directly to organs w/ other entering celiac plexus and distributed via vessels
What is the size, location, and surfaces of the liver?
- size: 5% of body weight in infants, 2% of body weight in adults
- location: upper right quadrant or epigastric and right hypochondriac regions; left lobe located in left upper quadrant
- surfaces:
diaphragmatic surface: conforms to concavity of diaphragm, covered by peritoneum except where it is in direct contact w/ diaphragm, IVC in direct contact w/ this surface
visceral surface: covered w/ peritoneum except where gallbladder and porta hepatis are located, transmits porta hepatis
(porta hepatis: transverse fissure on visceral surface, contains hepatic portal V., hepatic artery proper, nerve plexus, hepatic bile ducts, and lymphatic vessels)
- alcoholic type is most common type
- results from fatty changes and fibrosis
- causes hepatomegaly and hobnail appearance of liver surface
cirrhosis
What are the characteristics of the liver lobes?
- right lobe: larger than left, includes quadrate and caudate lobes which are separated by porta hepatis
caudate lobe: between IVC and falciform ligament
quadrate lobe: between gallbladder and falciform ligament
- left lobe: smaller than right lobe, separated from right lobe by the falciform ligament
What are the ligaments of the liver?
- bare area of the liver is in direct contact w/ the diaphragm
- coronary ligaments: reflection of visceral peritoneum from liver to respiratory diaphragm, surrounds bare area of liver
- right and left triangular ligaments are on the superior outer edges of the liver
- falciform ligament: fold of peritoneum caused by ligamentum teres hepatis/round ligament of liver (remnant of left umbilical vein)
- receives dual blood supply from:
hepatic artery: carries oxygenated blood from common hepatic artery to liver
hepatic portal vein: carries venous blood from stomach, intestines, spleen, and gallbladder
- portal triad: hepatic artery, portal vein, bile duct; surrounded by hepatoduodenal ligament
- pringle maneuver: surgical maneuver where a atraumatic hemostat is used to clamp the hepatoduodenal ligament (free border of the lesser omentum) interrupting the flow of blood through the hepatic artery and the portal vein and thus helping to control bleeding from the liver
hepatic portal
What is the location and relationships of the pancreas?
- location: level of L1-2 vertebrae
-
relationships:
anterior: lesser sac (omental bursa) and stomach
posterior: aorta, IVC, splenic V., common bile duct, right crus of diaphragm, left kidney and vessels, left suprarenal (adrenal) gland, superior mesenteric A./V.
right: duodenum (2nd part)
left: spleen
inferior: duodenum (3rd part)
What are the different parts of the pancreas?
- head: lies in curvature of the duodenum
- neck: indistinct, joints head to body, overlies superior mesenteric artery
- body
- tail: located in splenorenal ligament, its tip is adjacent to hilum of spleen
- uncinate process: adjacent to head, superior to 3rd part of duodenum
What are the parts and function of the gallbladder?
- pear-shaped organ attached to liver by CT in liver fossa
- 3 parts: fundus, body, neck
- cystic duct: connects neck to common hepatic duct
- function: stores (up to 50 ml) and releases bile
- BS from cystic artery (usually off right hepatic A. but this varies)
- innervation from celiac plexus
What are the different ducts a/w the pancreas and biliary tree?
- hepatic ducts: from right and left hepatic lobes
- common hepatic ducts: combined hepatic ducts
- cystic duct: connects gallbladder to common hepatic duct
- bile duct: combines cystic and common hepatic duct
- main pancreatic duct: begins in tail and courses to head, usually joined by accessory duct in the head, contains the sphincter of the main pancreatic duct which prevents bile from entering pancreas, joins common bile duct
- accessory pancreatic duct: may have a separate opening in the duodenum at the minor duodenal papilla
- hepatic ampulla (of Vater): formed by union of common bile duct and main pancreatic duct; a/w sphincter of Oddi (hepatopancreatic sphincter) and major duodenal papilla
- clinically known as “cholelithiasis”
- composed chiefly of cholesterol crystals
- can be lodged in several structures such as the cystic duct, hepatic duct, or the hepatopancreatic ampulla
- blockage of hepatopancreatic ampulla blocks both common bile duct and main pancreatic duct, results in bile backing up into pancreas and causes pancreatitis
gallstones
What is the arterial supply to the abdominal foregut?
arteries are off the celiac trunk
common hepatic artery >
- gastroduodenal artery >
right gastro-omental (gastroepiploic artery)
superior pancreaticoduodenal artery
supraduodenal artery
- right gastric artery
- hepatic artery proper (portal triad) >
right and left hepatic artery
cystic artery
splenic artery (tortuous) >
- short gastric arteries
- left gastro-omental (gastroepiploic) artery
- pancreatic branches >
dorsal pancreatic
great pancreatic artery
left gastric artery >
- esophageal branch
What are the possible arterial variations for the cystic artery and heptatic artery?
- cystic artery: arises within the cystohepatic triangle of Calot, see bottom image for variants
- hepatic artery: blood supply can also be from celiac trunk (A), SMA (B), and right/left hepatic arteries; see top and middle of image for variants
What are the possible hepatic duct variations?
- there is usually right and left hepatic branches that coincide w/ the right and left hepatic arteries
- the hepatic duct branches combine into the common duct
- however, there can be duct branches coming off the cystic duct, as well as multiple hepatic duct branches coming off the common duct
What are the borders and contents of the cystohepatic triangle of Calot?
borders:
- medial: common hepatic duct
- inferior: cystic duct
- superior: inferior visceral surface of the liver
contents:
- right hepatic artery: formed by bifurcation of proper hepatic artery into right and left branches
- cystic artery: typically arises from right hepatic artery and traverses the triangle to supply gallbladder
- lymph node of Lund: first lymph node of the gallbladder
- lymphatics
