Liver, Gall Bladder, and Pancreas Flashcards
Liver location
Upper right and part of the upper left quadrants of the abdomen
Liver functions
. Exocrine (bile) and endocrine secretion
. Removal of toxins from the blood
. Glycogen storage
. Synthesis of clotting factor and other essential proteins
Inferior border of liver
. Sharply defined margin separating diaphragmatic and visceral surfaces
. Extends inf. To costal margin in epigastric region
Diaphragmatic surface of liver
. Related to diaphragm and ant. Body wall
. Covered w/ visceral peritoneum except for the bare area that contacts the diaphragm posteroinferiorly
Visceral surface of liver
. Posteroinferiorly and toward the left
. Covered by visceral peritoneum and attached to adjacent structures by peritoneal ligaments
. Subdivided by fissures and grooves including porta hepatis, cystic fossa, IVC groove, ligamentum teres hepatis fissure, and ligamentum venosum fissure
Porta hepatis
Transverse fissure transmitting the hepatic aa., hepatic ducts, branches of hepatic portal v., nerves, and lymphatics
Cystic fossa
Gallbladder bed
Ligamentum teres hepatis
Obliterated fetal umbilical v.
Ligamentum venosum
Obliterated fetal ductus venosus
Falciform ligament
. Derivative of embryonic ventral mesentery
. Attaches liver to diaphragm and ant. Abdominal wall
. Ligamentum teres hepatis lies in its free inf. Margin
Coronary ligaments
. Reflections of peritoneum from diaphragmatic surface of the liver to the inf. Surface of the diaphragm
. Encircle bare area of the liver
Subphrenic recess
. Potential space btw visceral peritoneum on liver’s diaphragmatic surface and parietal peritoneum lining inf. Surface of diaphragm
. Divided by falciform ligament into separate R/L recesses
Hepatorenal recess (pouch of Morison)
. Potential space btw parietal peritoneum ant. To R kidney and visceral peritoneum on the liver’s visceral surface
. Communicates w/ R subphrenic recess and omental bursa
. In supine a potential site of fluid accumulation
Liver anatomical lobes
. Defined by fissures for ligamentum teres hepatis and ligamentum venosum, cystic fossa, porta hepatis, and IVC groove . Right lobe: largest . Left lobe: 1/6 of liver volume . Quadrate: inf. And ant. . Caudate: inf. And post.
Hepatobiliary functional lobes
. Functional units defined by branching of biliary ducts and blood vessels
. R/L hepatobiliary lobes
Right hepatobiliary lobe
. Supplied by R hepatic a. And right branch of hepatic portal v.
. Drained by R hepatic duct
. Includes parts of R anatomical and caudate lobes
Left hepatobiliary lobe
. Supplied by L hepatic a. And left branch of hepatic portal v.
. Drained by L hepatic duct
. Includes L anatomical and quadrate lobes as well as portions of R anatomical and caudate lobes
Hepatobiliary divisions and segments
. Further branching of the biliary tree and its accompanying vessels
. Each lobe divided into 2 divisions
. 3 of 4 divisions are divided horizontally into 2 segments
. 4th division and the caudate lobe are considered separate segments, yielding 8 segments
. Self-contained functional units and segmental hepatic aa. Are end aa.
Liver transplant
1+ hepatobiliary segments are harvested w/ blood vessels and duct system intact
. Has inherent capacity for regeneration
Liver receives ____% of total cardiac output
20
Proper hepatic a.
. Only 20% of liver blood supply but majority of O2
. R hepatic a.: supplies R hepatobiliary lobe and gives rise to cystic a.
. L hepatic a.: supplies L hepatobiliary lobe
Hepatic portal v.
. 80% of liver blood supply
. Nutrient rich but O2 poor
. Formed by sup. Mesenteric and splenic vv. Union
. Connects capillary beds of GI tract and liver sinusoids
. Courses in R free margin of hepatoduodenal ligament post. To proper hepatic a. And bile duct
Portal v. Conveys _____ to the liver
. Substances absorbed by intestines
. Bilirubin and other products of RBC breakdown that are metabolized and secreted as bile pigment
Hepatic vv.
. Arterial and venous blood mingle in liver sinusoids before draining to IVC via R/L/middle hepatic vv.
. Tributaries of hepatic vv. Are intersegmental
. Drain more than one hepatobiliary segment
Intrasegmental branches in liver
. Occurs in portal vein and hepatic aa.
Portal venous system
. Valveless venous system
. Conveys nutrient-rich venous blood from GI system to liver via hepatic portal v.
Portosystemic (portacaval) anastomses
. Regions of overlap btw portal and system venous return
. Located at either end of GI tract and wherever GI organs come into direct contact w/ body wall (retroperitoneal)
Lower esophagus portosystemic anastomoses
. Esophageal tributaries of azygos system anastomose w/ esophageal tributaries of L gastric v.
Anal canal portosystemic anastomosis
. Rectal vv. Anastomose w/in rectal submucosa
Ant. Abdominal wall paraumbilical vv. Portosystemic. Anastomosis
. W/in falciform ligament
. Anastomose w/ sup. Veins in ant. Abdominal wall
Bare area of liver portosystemic anastomosis
Btw liver parenchyma and tributaries fo inf. Phrenic vv.
Portal hypertension
. Obstruction of venous return through liver
. Leads to inc. pressure in portal system and enlargement of anastomatic channels
. Can be caused by alcohol cirrhosis
Gastroesophageal varices
. Engorged vv. In esophageal submucosa
. Rupture leads to life-threatening
Caput medusae
Enlarged superficial vv. Radiated from umbilicus
. Observed in most extreme cases of portal hypertension
Ascites
Accumulation of serous fluid in peritoneal cavity
Portosystemic shunts
. Portal hypertension causes portal venosus pressure may be dec. by creation of surgical anastomoses btw portal v. And systemic venous return
Portacaval shunt
Diversion of the portal vein into IVC
Splenorenal shunt
Diversion of splenic v. Into left renal vein
. Necessitates removal of spleen
Transjugular intrahepatic portosystemic shunting (TIPS)
. Stent used to create a shunt btw hepatic portal v. And hepatic v.
Liver innervation
Hepatic plexus
Liver sympathetic fibers
. Presynaptic Conveyed by greater splanchnic nn.
. Synapse in celiac plexus
. Post-synaptic fibers follow arterial pathways to reach liver
Liver parasympathetic fibers
. Carried by ant. And post. Vagal trunks contribute to celiac plexus
. Follow arterial pathways to synapse on or near their target tissues
Visceral sensory liver fibers
. Cell bodies are located in dorsal root ganglia of T5-9(10)
. Fibers conveyed by greater splanchnic nn. And folllow sympathetic pathways in a retrograde direction
Liver lymphatics
. Liver produces 1/3 of lymph drained by thoracic duct
. Superficial lymphatics: deep to fibrous capsule of liver, post. Liver branches drain to phrenic lymph nodes or accompany hepatic vv. And IVC to each post. Mediastinal lymph nodes
. Deep lymphatics: follow branching of biliary tree
. Deep and superficial drain to cisterna chyli
Gallbladder
. Pear-shaped sac 10 cm long
. Adherent to cystic fossa on visceral surface of the liver at the function of the R and quadrate anatomical lobes
. Inf. Surface invested w/ peritoneum continuous w/ visceral peritoneum of the liver
. Stores and concentrates bile
. Contracts to discharge bile into duodenum via biliary duct system in response to hormones
Gall bladder anatomical relations
. Sup: separated from visceral surface of liver by fibrous liver capsule (no intervening peritoneum)
. Ant: projects on ant. Abdominal wall at level of transpyloric plane, at tip of R 9th costal cartilage
. Inf.: contact w/ transverse colon and 2st sup. Portion of duodenum
Gall bladder anatomical divisions
. Fundus: rounded ant. End
. Body: main saccular portion
. Neck: narrow post. Portion continuous w/ cystic duct
. Infundibulum (Hartmann’s pouch): dilation at junction of neck and cystic duct, assoc. w/ gallbladder disease, not always present
Cystic duct
. Continuous w/ neck of gallbladder
. Mucosa is thrown into spiral folds which maintain patency of the duct and function as a valve
Hepatic ducts (R/L)
. Intrahepatic biliary ducts unite to form the right and left hepatic ducts
. Drain the right and left hepatobiliary lobes
Common hepatic duct
. Formed by union of the right and left hepatic ducts
Bile duct
. Formed by union of cystic and common hepatic ducts
. Lies in free right margin of hepatoduodenal ligament, ant. To hepatic portal v. And right of proper hepatic a.
. Passes post. To 1st (sup.) portion of duodenum and head of the pancreas
. Joins terminal portion of main pancreatic duct to form hepatopancreatic ampulla of Vater
Major duodenal papilla
. Ampulla empties into 2nd (descending) portion of duodenum
Sphincter of the bile duct
. Duct joins ampulla
. Regulates flow of bile
. Circular smooth muscle fibers in walls of bile duct and ampulla
Hepatopancreatic sphincter of Oddi
. Ampulla opens on the major duodenal papilla
. Regulates discharge of bile and pancreatic secretions
Gall bladder blood supply
. Cystic a. Supplies majority of blood to gallbladder, cystic duct, and portions of hepatic and bile ducts
. Cystic a. Arises as branch of R hepatic a. And courses post. To common hepatic duct to reach cystic duct and gall bladder
. cystic a. Located w/in cystohepatic triangle of Calot
. Cystic vv. Drain to portal v. Or directly to liver
Cystohepatic triangle of Calot
. Visceral surface of the liver
. Cystic duct
. Common hepatic duct
Cholecystectomy complications
. Small vv. From gallbladder drain directly to liver and produce bleeding
. Variations in branching patterns of biliary ducts and blood vessels are common and contribute to high incidence of complications in gallbladder surgeries
Lymphatic drainage of gallbladder
. Follows blood supply
. Drains to cystic and hepatic lymph nodes before reaching celiac lymph nodes
Gallbladder innervation
. Gallbladder and biliary ducts supplied by hepatic plexus fibers
Biliary function
. When sphincter of bile duct is closed, bile secreted by liver is diverted to gallbladder for storage and concentration
. Ingestion of fatty foods triggers release of hormones that cause gallbladder to contract and sphincters relax, delivering bile to duodenum
. Blockage of biliary ducts causes bile to back up into liver producing jaundice
Biliary colic
. Gallbladder pain referred to epigastric region of ant. Abdominal wall (T5-9) and is typically diffuse
. Severe inflammation involves parietal peritoneum which is innervated by somatic afferent fibers
. Sharp pain to R hypochondriac region can radiate to inf. Angle of R scapula
. Reflexive contraction of muscles innervated by involved nn. Causes abdominal rigidity
.
Inflammation of diaphragmatic region innervated by phrenic n. (C3-5) may cause ____
Referred pain in right neck and shoulder
Cholecystitis
. Gall bladder disease
. Most common in obese women of middle age that had have multiple pregnancies
. Chronic symptoms may be exacerbated after eating and when supine due to shifting of stones into bladder neck
. Gallstone impaction produces severe, acute symptoms
. May require surgical innervation
Pancreas anatomical relations
. Secondarily retroperitoneal
. Lies transversely across post. Abdominal wall at L2 level
. Located post. To stomach, ant. To sup. Mesenteric vessels btw duodenum and spleen
Pancreas head
. Lies w/in C-loop of duodenum and immediately ant. To and in contact w/ IVC, R renal vessels, and L renal v.
Uncinate process of pancreas
. Inferomedial projection of the head post. To sup. Mesenteric vessels
Pancreas neck
. Narrowing btw head and body
. Lies ant. To sup. Mesenteric vessels and post. To pyloric of stomach
Pancreas body
. Extends transversely to left
. Lies immediately ant. To abdominal aorta, L suprarenal glands, L kidney, and renal vessels
Pancreas tail
Tapering terminal portion related to L kidney, hilus of spleen, and L colic flexure
Main pancreatic duct
. Drains tail and body of pancreas
. Turns inf. W/in head of pancreas and joins bile duct to form hepatopancreatic ampulla that drains to duodenum at major duodenal papilla
Accessory pancreatic duct
. Drains head of pancreas and empties at the minor duodenal papilla sup. To major papilla
. Communicates w/ main pancreatic duct, provides alternate outlet for pancreatic secretions
Pancreas blood supply
. Head of pancreas supplied by parallel arterial arcades domed by ant. And post. Branches of sup. And inf. Pancreaticoduodenal aa.
. Body and tail of pancreas are supplied by pancreatic branches of splenic a.
. Pancreatic vv. Drain to hepatic portal v.
Pancreas lymphatics
. Follow arterial pathways
. Filtered through pancreaticosplenic lymph nodes distributed along splenic a. But some passes to pyloric lymph nodes before reaching Celiac lymph nodes
Pancreas sympathetic fibers
. Presynaptic Thoracic splanchnic nn.
. Postsynaptic: celiac and sup. Mesenteric plexuses and follow arterial fibers
Parasympathetic fibers on pancreas
. Ant. And post. Vagal trunks
. Participate in formation of celiac and sup. Mesenteric plexuses and follow arterial pathways to synapse near target tissue
Pancreas visceral sensory
. Cell bodies located in dorsal root ganglia of T5-10
. Follow sympathetic pathways in retrograde direction