Anatomy - Abdominal Organs: Solid Viscera Flashcards
What is the position of the spleen?
The spleen lies between the 9th and 11th ribs (left hypochondriac region, between the diaphragm and stomach/colon).
Which ribs potect the spleen?
9, 10 and 11
3 ligaments that support the spleen
- Splenorenal ligament
- Gastrosplenic ligament
- Phrenicocolic ligament
The following ligaments connect the spleen to…
* Splenorenal ligament
* Gastrosplenic ligament
* Phrenicocolic ligament
Splenorenal ligament: Connects the spleen to the body wall
Gastrosplenic ligament: Connects the spleen to the stomach
Phrenicocolic ligament:
Does not connect to the spleen, but helps support it (ligament that attaches the colon to the diaphragm)
3 spleen impressions
gastric
colic
renal
Blood supply of the spleen
Splenic artery (main branch of celiac trunk)
Splenic vein (joins SMV to form hepatic portal vein)
Spleen rupture can occur as a result of blunt force trauma. How can we repair the spleen?
We can suture the greater omentum (a highly vascularized structure) to the ruptured spleen to revascularize the organ.
What do we call a procedure by which the spleen is removed?
Do we perform spleen transplants?
Spleen removal is called a splenectomy.
The spleen is NOT essential for life, so it can be safely removed (liver and bone marrow will take over its functions).
Splenomegaly
Enlarged spleen - etiologies are usually associated with increased workload conditions (e.g. hemolytic anemia).
How can we treat splenomegaly?
Splenectomy
4 regions of the pancreas
Head
Neck
Body
Tail
What is the uncinate process?
A part of the head of the pancreas (develops separately from the rest of the pancreas in the fetus)
Majority of the pancreas is…
a) intraperitoneal
b) retroperitoneal
b) retroperitoneal
Which part(s) of the pancreas is are intraperitoneal?
Tail of the pancreas
(because it extends into the splenorenal ligament)
The superior mesenteric artery and vein cross the duodenum and pancreas. Describe how they are all positioned relative to each other.
The superior mesenteric artery and vein run anterior to the duodenum, but posterior to the neck of the pancreas.
They are “sandwiched” between the pancreas and duodenum.
What is the position of the uncinate process relative to the superior mesenteric artery and vein? What are the implications of this layout?
The uncinate process (and duodenum) are posterior to he superior mesenteric vessels but anterior to the abdominal aorta, which can result in Nutcracker syndrome.
The main pancreatic duct drains to…
The accessory pancreatic duct drains to…
Main pancreatic duct: major duodenal papilla
Accessory pancreatic duct: minor duodenal papilla
The papilla are located in the 2nd (descending) part of the duodenum
Bile duct function
Carries bile from the liver to the duodenum; joins the main pancreatic duct to open into the major duodenal papilla
Bile is produced in…
Bile is stored in…
Bile is produced in the liver
Bile is stored in the gallbladder
The common bile duct has 2 branches…
- Common hepatic duct (connecting to the liver)
- Cystic duct (connecting to the gallbladder)
What do we call the small “reservoir” where your common bile duct and pancreatic duct meet before entering the duodenum?
Hepatopancreatic ampulla
What is the name of the sphincter located in the major duodenal papilla?
Hepatopancreatic sphincter
What arteries supply the head of the pancreas?
Superior & inferior pancreaticodudodenal arteries (also supply duodenum).
What arteries supply the rest of the pancreas (not the head)?
Branches of the splenic artery.
The main branch is called dorsal pancreatic artery, which then branches into transverse pancreatic arteries.
Which liver lobe (right/left) is smaller? How are they separated?
Left lobe is smaller than the right lobe. They are separated by the falciform ligament.
The gallbladder is tucked under…
a) the left lobe of the liver
b) the right lobe of the liver
b) the right lobe of the liver
Name the 4 lobes of the liver (inferior view)
- Right lobe
- Left lobe
- Quadrate lobe (between the gallbladder and round ligament)
- Caudate lobe (between the IVC and ligamentum venosum)
What is the porta hepatis?
Region where the portal triad enters the liver:
* hepatic bile duct
* proper hepatic artery
* portal vein
Describe the anatomical vs functional lobes of the liver, and what separates them in each case
Anatomical: separated by falciform ligament
Functional: defined by ductal and vascular anatomy separated by gallbladder/IVC)
Describe the ducts of the liver and gallbladder
The cystic duct (from the gallbladder) and the common hepatic duct (from the liver) connect to form the bile duct.
Where is bile produced?
In the liver (stored in gallbladder)
Where does bile go when the hepatopancreatic sphincter is closed?
It backs up into the gallbladder
How does the common hepatic artery (from the celiac trunk) branch?
It branches into the proper hepatic artery, which branches into the right and left hepatic arteries (to liver) and the cystic artery (to the gallbladder).
The portal triad is contained within a ligament called…
hepatoduodenal ligament (component of the lesser omentum)
What is the difference between the portal system and caval system?
Portal system: drains the blood from the GI tract (brings it to the liver) - it then connects to the caval system
Caval system: drains blood from the body wall, limbs, and structures that do not pass through the liver, returning it directly to the heart via the superior and inferior vena cava
What are portacaval anastomoses?
Connections between the portal and caval (systemic) venous systems.
Postacaval anastomoses: 4 important sites
- esophageal
- paraumbilical
- rectal
- retroperitoneal
What is the most common cause of portal hypertension?
Cirrhosis
Under what condition will blood from the portal system move into the caval system rather than going to the liver?
Portal hypertension
In portal hypertension, shunting of blood from the portal to the caval system results in…
distension of the caval veins, which gives rise to esophageal varices (esophageal anastomoses) and caput medusae (paraumbilical anastomoses).
If a dug is administered orally, what percentage will go to the liver? What is the drug is absorbed rectally instead?
100% of the blood from the stomach goes to the liver, and the first-pass effect will reduce the amount of active drug that reaches the systemic circulation.
However, if it is adminstered rectally, 50% of the drug will bypass the liver.
Which rectal veins carry blood to the liver? Which rectal veins carry blood directly to the caval system (systemic)
Superior rectal vein -> portal system (liver)
Middle and inferior rectal veins -> caval system (systemic)
Sympathetic nervous system effect on the GI vs parasympathetic
SNS: decreases GI activity (fight or flight)
PSNS: increases GI activity (rest and digest)
Define GI activity as influenced by the SNS and PSNS
Gi activity:
* muscular contractions (force & frequency)
* glandular secretions
* blood flow to GI organs
PSNS will increase these factors, SNS will decrease these factors.
