10/27: Portal-Caval Venous System Flashcards
What do gut derivatives drain?
Blood to the liver first because they are carrying deoxygenated blood and nutrients that need to go to the liver
The liver then passes venous drainage to the IVC
What is the function of the portal vein in the gut?
Nearly all venous blood from the gut is drained to the liver via portal vein
What is the (obliterated) umbilical vein used for?
To carry blood in from the umbilical cord
What is the umbilical vein accompanied by?
Tiny paraumbilical veins, which remain patent
What do the paraumbilical veins drain?
Blood form skin around the umbilicus so that blood goes into portal vein
What does the hepatic vein drain?
Blood from the liver to the IVC
Splenic v and other foregut v have same names as arteries EXCEPT?
The celiac artery
What does the superior mesenteric vein drain?
Midgut
What does the inferior mesenteric vein drain?
Hindgut
What does the inferior mesenteric vein join and empty into?
Splenic vein
Where does the splenic vein run?
From hilum of spleen behind pancreas and stomach (inferior of a)
What is the portal vein formed by and run?
Splenic and superior mesenteric vein; behind neck of pancreas
Where does the pancreaticoduodenal veins drain?
Into portal vein and superior mesenteric
Further you are to the left of the foregut, the more likely you are to drain into the ____________. On the right side, you are more likely to drain into the ______________.
Splenic vein; portal vein
Where do foregut veins drain?
- To the portal vein
- to the splenic vein
- to the superior mesenteric vein
What veins drain to the portal vein?
Left/right gastric vv
Cystic v
Pancreaticduodenal vv (superficial veins around umbilicus)
What veins drain into the splenic vein?
Short gastric vv
Left gastroomental v
What veins drain into superior mesenteric vein?
Right gastroomental v
Pancreaticduodenal vv
Tiny veins in the anastomoses can become engorged as a response to _____________
Portal hypertension
What is portal hypertension?
Passage of venous blood from the portal vein through liver is impeded
What are engorged veins called?
Varices
What can portal hypertension be caused by?
Cancer, cirrhosis, thrombosis, or congenital malformation of the IVC
What do anastomoses of the left gastric vein (branch of portal v) with the azygos vein (branch of SVC) result in?
Esophageal rupturing when food is swallowed and internal bleeding
*Most common cause of death in patients with hypertension
What do anastomoses of the superior rectal vein (branch of portal v) with the middle and inferior rectal veins (branches of IVC) result in?
Rectal varices, of which bright red bleeding is a symptom. Upper GI bleeding is tar-colored stool
What do anastomoses of the paraumbilical vein (branches of portral v) and thoracoepigastric and the inferior and superior epigastric veins (branches of IVC) result in?
Form caput medusae (Medusa’s head) pattern out from the umbilicus
What do anastomoses between the inferior mesenteric vein (branch of portal v) and veins of the posterior abdominal wall, which are IVC branches and which are connected to the hemiazygos vein (branch of SVC) result in?
Very deep in the body, rarely becomes symptomatic
Visceral pain axons for the thorax and abdomen follow sympathetic pathways ________________
Backwards, as far as the spinal nerve proper
After passing through the sympathetic pathway backwards, where do they pass through?
Dorsal root
Where are the cell bodies found?
In the dorsal root ganglia
Where is somatic pain felt?
By the abdominal walls, including parietal peritoneum which is pain sensitive (particularly when inflamed and stretched)
What carries somatic pain?
Ventral rami of spinal nerves
What is visceral pain felt by?
Internal organs and brought about by ischemia, prolonged smooth muscle contraction, and distention
What is visceral pain carried by?
Visceral pain axons that run alongside sympathetics
Where isn’t pain felt by?
Visceral peritoneum that covers mesenteric arteries
Nor is pain felt by mesenteries
