Week 1: Liver and Lymphatic drainage

Question 1

Direction of flow of lymphatics in the abdomen

Answer 1

lymphatic drainage follows the reverse path of the arteries as lymph flows from the regional nodes associated with the viscera to lymph nodes located on the abdominal aorta

lymph flows from the pre-aortic nodes to the cisterna chyli, the dilated proximal end of the thoracic duct to eventually enter the venous circulation

Question 2

Naming of lymph nodes

Answer 2

These pre-aortic lymph nodes are named according to their associated artery

celiac nodes (foregut)

SMA nodes (midgut)

IMA nodes (hindgut)

Question 3

Identify

Answer 3

Question 4

Innervation of the abdominal viscera

Answer 4

innervation of the abdominal viscera has a similar pattern to the arterial supply but in addition, the enteric nervous system provides an “intrinsic” network of ganglia with connections to the autonomic nervous system which coordinates peristalsis (movement) and secretion

Question 5

Location of the enteric ganglia and nerve plexus

Answer 5

are the myenteric plexus and the submucosal plexus within the layers of the bowel wall

Question 6

Describe autonomic innervation of the gut

Answer 6

Question 7

Describe innervation of the forgut

Answer 7

Question 8

Describe innervation of the midgut and hindgut

Answer 8

Question 9

Summary of the neurovascular supply of the gut

Answer 9

Question 10

What is the largest solid organ in the body?

Answer 10

The liver

Question 11

Anatomical divisions of the liver

Answer 11

right and left lobes

two smaller lobes (caudate and quadrate) are considered part of the left lobe

Question 12

Liver receives venous drainage from?

Answer 12

the GI tract, accessory organs of the GI tract and the spleen via the portal vein

Question 13

Liver storage

Answer 13

glycogen

fat

protein

vitamins

and iron

Question 14

Liver produces and functions

Answer 14

fuels

plasma proteins

metabolizes toxins modifies hormones

produces bile acids

excretes substances (bilirubin) in bile via exocrine secretion

Question 15

Liver vascular supply

Answer 15

supplied with oxygenated blood by the proper hepatic artery which is a branch of the common hepatic from the celiac trunk which runs within the hepatoduodenal ligament along with the portal vein and common bile duct anterior to the epiploic foramen

Question 16

Describe the blood supply to the liver

Answer 16

Question 17

Identify

Answer 17

Question 18

Describe blood flow in the liver

Answer 18

blood enters the liver through the proper hepatic artery (30%) and portal vein (70%) and leaves via the hepatic veins which drain into the IVC before it enters the right atrium

Question 19

Describe the biliary system

Answer 19

bile leaves the liver via the right and left hepatic ducts after draining the right and left lobes of the liver and enters the common hepatic duct

it enters the cystic duct and is stored and concentrated in the gallbladder

on stimulation, bile leaves the gallbladder, enters the cystic duct and passes down the common bile duct

it enters the hepatopancreatic ampulla (of Vater) which is surrounded by a smooth muscle sphincter (of Oddi) Bile then empties into the second part of the duodenum at the major duodenal papilla

Question 20

What is the pancreas?

Answer 20

an exocrine and endocrine organ that lies posterior to the stomach in the posterior wall of the lesser sac

Question 21

Pancreas location and shape

Answer 21

• It is retroperitoneal except for the distal tail which contacts the spleen
• the pancreas has a head, neck, body and tail with the head nestled in the C shaped curve of the duodenum

Question 22

Pancreas ducts

Answer 22

In addition to the main pancreatic duct which joins the common bile duct at the hepatopancreatic ampulla, exocrine pancreatic secretions exit via the accessory pancreatic duct emptying into the duodenum at the minor duodenal papilla

Question 23

What is the spleen?

Answer 23

A functionally larger lymph node

Question 24

Spleen location

Answer 24

• that lies in the left upper quadrant (hypochondrium) posterolateral to the stomach and protected by the ribs
• It is connected to the stomach via gastrosplenic ligament and to the left kidney by the splenorenal ligament

Question 25

Hepatic portal system function

Answer 25

carries blood from the abdominal viscera to the liver

Question 26

Portal system features

Answer 26

in a portal system arterial blood flows into a capillary system (in GI viscera) then into veins (portal tributaries) and finally into more capillaries (liver sinusoids) before being collected by veins that return the blood to the heart (hepatic veins and IVC) The tributaries of the portal system are named analogously to the veins in contrast to the systemic circulation there are no valves in the portal system of veins

Question 27

What are portosystemic anastomoses?

Answer 27

because of the lack of valves in the portal system, anastomoses (connections) between the portal and systemic veins called portosystemic anastomoses, allow blood to return to the heart via the systemic circulation when a major vein of the portal system is occluded or restricted

Question 28

The most important portosystemic anastomoses

Answer 28

around the lower esophagus, rectum, umbilical region, retroperitoneal anastomoses

Question 29

Portal blood flow restriction

Answer 29

backflows into the systemic circulation engorged veins from this increased blood flow can result in esophageal varices, hemorrhoids, and cutaneous engorged veins around the umbilicus called caput medusae

Question 30

cirrhosis of the liver and portal blood flow

Answer 30

cirrhosis of the liver leads to fibrosis and disrupts portal blood flow leading to portal hypertension and engorgement of the portosystemic anastomoses

Question 31

Major cause of cirrhosis

Answer 31

alcoholic liver disease

Question 32

Describe the portal system

Answer 32

Question 33

Retroperitoneal structures

Answer 33

kidneys suprarenal glands ureters abdominal aorta inferior vena cava

Question 34

Abdominal aortic aneurysm

Answer 34

localized abnormal dilation of the aorta that occurs when the structure of the aortic wall is compromised Hypertension and atherosclerosis are major causes

Question 35

Abdominal aortic aneurysm symptoms

Answer 35

Abdominal and back pain, nausea, early satiety but up to 75% are asymptomatic

Question 36

Common causes of abdominal aortic aneurysm

Answer 36

Hypertension and atherosclerosis

Question 37

Abdominal aortic aneurysms diagnosis

Answer 37

often discovered incidentally as an abdominal mass (often palpably pulsating)

Question 38

Ruptured abdominal aortic aneurysm

Answer 38

A sharp tearing back pain accompanies rupture of an aortic aneurysm

Question 39

Inferior Vena Cava

Answer 39

is part of the systemic or caval system of veins that drain blood from the body wall At the pelvic brim, the common iliac vein is formed by the internal and external iliac arteries Two common iliac veins join to form the IVC which receives drainage from the gonads, kidney, posterior abdominal wall, liver and diaphragm The IVC drains into the right atrium of the heart

Question 40

Describe the abdominal venous system

Answer 40