Exam 3: Hepatic Flashcards
_____ is the largest solid organ in the body
Liver
the liver is _______% of adult body weight and ____% of neonate body weight
2; 5
the liver weighs about ________ g
1500
the liver sits in the thoracic portion of the abdominal cavity from ribs ______ - _______
7; 11
______________ is what divides the liver into the left and right lobes
falciform ligament
What are the different anatomic lobes of the liver?
- right lobe
- left lobe
- caudate lobe
- quadrate lobe
T/F: the liver is the only organ with a dual blood supply
True
surgical liver anatomy has __________ segments
8 (1-8)
Why is knowing the hepatic segments important as an anesthetist?
This becomes extremely important when we are doing segmental resections of the liver
What is the portal triad?
- Bile Duct
- Hepatic Artery
- Portal Vein
The liver receives approximately _____% of cardiac output via a dual arterial and venous blood supply
25-30
The _____and ______ enter the liver and progressively branch until terminating in the hepatic sinusoids.
hepatic artery ; portal vein
Changes in hepatic artery or portal vein blood flow may not result in an overall change in total hepatic flow due to the _______
hepatic artery buffer response (HABR)
- This response is a semireciprocal autoregulatory mechanism whereby changes in portal flow inversely affect hepatic arterial flow
the hepatic artery supplies _____% of blood to the liver, and the hepatic portal vein supplies ____% of blood to the liver; however, both supply ____% of O2
20-25 ; 70-75 ; 50
if the portal vein supplies 70-75% of blood flow to the liver, why does it only supply 50% of Oxygen?
blood in hepatic portal vein is partially deoxygenated and nutrient rich 2/2 blood coming into it from splanchnic circulation
the hepatic artery comes from the _____________ artery
celiac
the portal vein comes from the ____________ & __________ veins
splenic vein; inferior mesenteric vein
what should your hepatic artery pressure be?
should be the same as the SBP bc it comes right off the Ao
What is the pressure in the hepatic portal vein?
7-10 mmHg
O2 sat of the hepatic portal vein
85%
the low pressure system of the hepatic portal vein allows for what ?
- large venous reservoir in the liver
- allows to compensate 25% of volume loss
- can hold 1 L of volume
SNS innervation to the liver
T3-T11
parasympathetic innervation to the liver
R/L vagus nerves
R phrenic nerve
what are the vasoconstricting receptors of the hepatic artery?
alpha 1 adrenergic
what are the vasoconstricting receptors of the portal vein?
alpha 1 adrenergic
D1 dopaminergic
what are the vasodilating receptors of the hepatic artery
- B2 adrenergic
- D1 dopaminergic
- cholinergic
the D1 dopaminergic receptor causes _____________ in the hepatic artery, but causes ________________ in the portal vein
vasodilation; vasoconstriction
_________________ is the functional unit of the liver
hepatic lobule
there are approximately _________________ hepatic lobules in a normal liver
50,000 - 100,000
what is in the center of each hepatic lobule
central vein
all hepatic veins course through the hepatic lobule draining into the ____________, which then drains into the _______________
central vein; IVC
describe the hepatic blood flow
- in from hepatic artery and portal vein
- through the sinusoids
- into the central veins
- Hepatic veins
- then into the IVC
how long does it take for blood to flow from the portal vein to the central vein?
8-9 seconds
______________ is on each side of the hepatocyte which allows for large proteins to come through
fenestrated endothelium
what is the fx of bile canaliculi
they collect the bile that the hepatocyte is producing –> bile duct
What are the different functions of the liver? (Vasculature and metabolic)
vasculature:
1. blood reservoir
2. blood cleansing via kupffer cells
metabolic liver fx:
1. bile formation and excretion
2. protein synthesis
3. glycogen storage
4. protein metabolism
5. insulin clearance
6. lactate conversion into glucose
7. drug metabolism
8. biotransformation
The normal blood volume in the liver = __________, but can hold up to __________
450 mL; 1 L
_____ cells line the sinusoids and function to cleanse the blood
kupffer cells
_____ is stored glucose
Glycogen
To maintain a steady blood glucose level, the liver moderates _______ and _______.
gluconeogenesis; glycogenolysis
________ is the formation of glucose from the noncarbohydrate molecules lactate and pyruvate, as well as amino acids, all of which are products of anaerobic and catabolic metabolism. It is stimulated by ____________________.
Gluconeogenesis; a decrease in glycogen stores
During periods of fasting, the liver maintains blood glucose at relatively normal levels through __________.
glycogenolysis
Initiated by epinephrine and glucagon, _______ is the process of liberating glucose from glycogen stores found in the liver (and skeletal muscle).
glycogenolysis
________ may be encountered in patients with severe liver disease due to dysfunctions in insulin clearance, a decrease in glycogen capacities, and impaired gluconeogenesis.
Hypoglycemia
_____ is the formation of of glycogen from glucose
Glycogenesis
Most proteins are synthesized by the liver EXCEPT ________
immunoglobulins
What is the MOST important protein produced by the liver?
Albumin
What happens to protein synthesis as a result of liver dysfunction?
Decreased albumin
- Decreased plasma oncotic pressure
- Ascites
- Increased Vd –> Increased NMB
Decreased drug binding
- Exaggerated effect of some drugs (Barbiturates)
Decreased plasma pseudocholinesterase
- Prolonged succs action
______ is a breakdown product of heme metabolism and is often classified as unconjugated or conjugated.
Bilirubin
Explain the process of bilirubin metabolism
Heme is converted to unconjugated bilirubin in the reticuloendothelial cells of the spleen. This unconjugated bilirubin is not soluble in water and is neurotoxic at sufficiently high levels. It is then bound to albumin and transported to the liver. Once in the liver, the unconjugated bilirubin is conjugated with glucuronic acid. Bilirubin is then incorporated into the bile and secreted into the intestine, where it is metabolized by bacterial enzymes and predominantly excreted in the feces.
Bile is created in the _____
Bile is stored and concentrated in the ______
Liver ; Gallbladder
Bile is released from the gallbladder in response to ______
to the intestinal hormone cholecystokinin (CCK)
_______ assists in the absorption of fat and fat-soluble vitamins (vitamins A, D, E, and K).
Bile secretion
What are the fat-soluble vitamins?
A, D, E, K
All Dogs Eat Kats
Liver disease may result in impaired bile production or flow, leading to…
- steatorrhea
- vitamin K deficiency
- delayed removal of active drug metabolites
All clotting factors are produced by the liver except
VIII and vWF
What are the Vitamin-K-dependent clotting factors?
II, VII, IX, X
