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Flashcards in Hepatic Physiology Deck (73)
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1

Ascites

Fluid accumulation in peritoneal cavity
- liver dysfunction is the major cause

2

Icterus

Elevated bilirubin levels
- aka: hyperbilirubinemia, jaundice

3

Cirrhosis

Condition in which normal cells are replaced by scar tissue
- end stage occurrence

4

Portal hypertension

Hypertension in the portal vein and its branches
- elevated bp in the portal vein or elevation in interstitial hydrostatic pressure

5

Metabolism

Sum of all anabolic and catabolic reactions as it relates to use of all nutrients

6

Liver functions

- filtering and storage of blood (largest cardiac output)
- metabolism of carbs, proteins, fats
- metabolism of hormones, drugs, toxins
- formation of cholesterol and bile (fat synthesis)
- storage of vitamins and iron
- production of coagulation factors
- production of plasma proteins
- lymph formation

7

The liver makes every ____ in the body

Protein

8

_____ is relevant during ascities

Lymph formation
- excess lymph gets into the peritoneal cavity

9

Liver lobule

Basic functional unit of liver

10

Hepatocytes

Main liver cells
- produce bile, which is drained into bile canaliculi

11

Sinusoids

Protein, lymph production
- holes in between endothelial cells leak into lymphatics

12

Portal vein

Main blood supply to the liver

13

Hepatic artery

2nd main blood supply
- filters bacteria coming from portal vein (hepatocytes)

14

Kupffer cell

Macrophages, makes sure bacteria does not go into systemic circulation

15

Liver structure

Largest internal organ
- 2-5% total body weight
- receives 30% of cardiac output

16

Liver lobes

6 lobes
- right and left medial
- right and left lateral
- quadrate
- caudate

17

Venous sinusoids

Lined by endothelial cells with large pores to allow movement of plasma proteins
- contains Kupffer cells that keep less than 1% of GI bacteria from entering systemic circulation (defense mechanism)

18

Lymph formation

50% of lymph is formed in the liver
- sinusoidal endothelial cell leak fluid/proteins into "space of Disse"
- lymph from liver has protein conc of 6 g/dl

19

Lymph flow

Lymph --> space of Disse --> lymph vessels --> lymphatic system

20

Increased sinusoidal pressure increases lymph production

Any disease of liver, especially chronic diseases
- fibrosis, cirrhosis
- once pressure rises enough, the liver sweats lymph (ascities)
- liver lymph volume can increase by 1 liter or more

21

Extramedullary hematopoiesis

Production of blood cells outside of bone marrow during times of need
- cytokine stimulation
- hypoxia

22

Liver blood flow breakdown

- 20% from hepatic artery
- 80% from portal vein

23

Liver oxygen supply breakdown

- 50% from hepatic artery
- 50% from portal vein

24

Portosystemic shunts

Shunting of blood from portal circulation to systemic circulation without passing through the liver
- congenital
- acquired

25

Congenital shunts

Intrahepatic or extrahepatic vessel that does not allow blood to take a normal course thru the liver
- ex: portocaval shunt where portal vein empties directly into caudal vena cava

26

Consequences of congenital shunts

- impaired liver development = stunted growth
- liver dysfunction = build up of toxins (ammonia), poor ability to metabolize anesthetics
- liver failure
- end stage cirrhosis without repair

27

Portal pressures

- pressure in portal vein: 9 mmHg
- pressure in hepatic vein leading to vena cava: 0 mmHg
- low pressure gradient gets blood from intestines and spleen, thru liver, into vena cava and back to right atrium

28

Ascites

Sweating from surface of the liver due to increased hydrostatic pressure in hepatic veins
- fluid similar to plasma in regards to protein content
OR: due to increased hydrostatic pressure in vena cava
- increases lymph flow

29

Causes of portal hypertension

- cirrhosis
- severe infection
- chronic biliary tract obstructions
- portal vein thrombosis (increase hydrostatic pressure)

30

Consequences of portal hypertension

- GI edema/ulceration
- severe GI signs and protein loss
- ascites
- acquired portosystemic shunts