Liver Flashcards
Which structure is responsible for eliminating bacteria from the liver?
a. Kupffer cell
b. canaliculus
c. sinusoid
d. acinus
a. Kuppfer cell
The largest internal organ is the
liver
the functional unit of the liver is
the lobule
__________- is another way to functionally classify liver tissue.
Acinus
The acinus encompasses the liver tissue that is served by
a single terminal branch of the hepatic artery
______________ in the acinus are organized into zones according to their proximity to the portal triad and central vein.
Hepatocytes
__________________ are the most susceptible to ischemic injury
Hepatocytes in zone 3
______________ remove bacteria from the portal blood before the blood enters the systemic circulation
Kuppfer cells
Bile is produced by the ________ and stored in the ________
hepatocytes; gallbladder
What is the specific path that bile follows?
canaliculi–> bile duct–> common hepatic duct–> common bile duct–> ampulla of Vater–> duodenum
Lymph and proteins drain into __________ before they empty into the lymphatic duct
space of Disse
___________ is a connective tissue covering that encapsulates the liver along with parts of the hepatic artery, portal vein, and bile ducts.
Glisson’s capsule
What ligaments attach to the anterior abdominal wall attachments?
falciform and round ligaments
What ligaments attach to the diaphragmatic attachments?
coronary ligament and triangular ligaments
The liver receives SNS innervation from
T3-T11
A lobule is hexagonal in cross section with (how many veins)?
a central vein at its center and portal veins at its six corners
Sinusoids can be compared to
capillaries (serve this function)
The arterioles of the liver are the
hepatic artery and portal vein
The acinus is divided into 3 zones that correspond to the
distance from the arterial oxygen supply (portal triad)
The highest concentration of CYP450 enzymes is in
zone 3
The _______ controls the flow of bile released from the common hepatic duct.
sphincter of Oddi
What are the 3 functions of bile?
- absorption of fat and fat-soluble vitamins
- excretory pathway for bilirubin and products of metabolism
- alkalization of the duodenum
Eating fat and protein increases release of ______________________; which stimulates _______ contraction & increases the flow of bile into the duodenum
Cholecystokinin; gallbladder
Which statement MOST accurately describes hepatic perfusion?
a. the hepatic artery provides 75% of liver blood flow
b. the portal vein provides 50% of liver blood flow
c. the hepatic artery provides 75% of the liver’s oxygen content
d. the portal vein provides 50% of the liver’s oxygen content
d. the portal vein provides 50% of the liver’s oxygen content
The liver receives about _______ of the cardiac output via a dual blood supply
30%
The portal vein provides _______ of the total liver blood flow and provides ____ of the liver’s oxygen supply
75%; 50%
The hepatic artery provides __ of the total liver blood flow and provides _____ of the liver’s oxygen supply.
25%; 50%
Is portal blood flow autoregulated?
Nope
Increased splanchnic vascular resistance ____________ portal vein flow
reduces
When there’s a reduction in portal vein blood flow, the hepatic arterial buffer response compensates by
increasing flow through the hepatic artery
_________________ impairs the response of the hepatic arterial compensation
severe liver disease; makes the diseased liver even more susceptible to hypoperfusion
_________ and ____________- reduce MAP and cardiac output which can reduce liver blood flow in a dose-dependent fashion.
Both general and neuraxial
The liver receives a dual blood supply from the
portal vein and hepatic artery
The following can increase splanchnic vascular resistance and decrease portal vein blood flow
SNS stimulation
pain
hypoxia
hypercarbia
Portal perfusion pressure is calculated by
Portal perfusion pressure= portal vein pressure- hepatic vein pressure
Normal portal vein pressure is
7-10 mmHg
Portal vein pressure of ____– is diagnostic for portal HTN
> 20-30 mmHg
Normal sinusoid pressure is
0 mmHg
Sinusoid pressure of __________ is diagnostic for portal HTN
> 5 mmHg
Portal hypertension reduces blood flow through the liver which produces back pressure to the following splanchnic organs:
vascular engorgement–> splenomegaly, & varices of the esophagus, stomach, & intestine
Additional physiologic consequences of portal hypertension include
ascites, spider angiomas, hemorrhoids, and encephalopathy
Perioperative factors that reduce liver blood flow include:
increased splanchnic vascular resistance (SNS stimulation, pain, hypoxia)
things that increase CVP (PPV, excessive hydration, & CHF)
some beta-blockers (propranolol)
intraabdominal surgical procedures (surgical retraction and release of vasoactive substances)
laparoscopic surgery (pneumoperitoneum)
The celiac artery provides blood flow to which 3 organs?
liver
spleen
stomach
The superior mesenteric artery provides blood flow to which 3 organs?
pancreas
small intestine
colon
Name 1 organ that receives blood flow from the inferior mesenteric artery.
colon
