physiology and pharmacology of the Liver

Question 1

what is a marker of liver function

Answer 1

albumin and PT time

Question 2

low albumin is a sign of what

Answer 2

CHRONIC LIVER problems and malnutrition

Question 3

what is hypoalbuminaemia also found in

Answer 3

hypercatabolic states (e.g. trauma with sepsis) and in diseases associated with an excessive loss (e.g. nephrotic syndrome, protein-losing enteropathy)

Question 4

what does the liver do

Answer 4

STORES

fat soluble vitamins - ADEK and B12

copper and iron

glycogen

DEGRADES

insulin, steroid hormones, ADH and glucagon

activates vitamin D to 25(OH)D

Question 5

where is albumin made and what does it do

Answer 5

in the liver

regulates the oncotic pressure of blood and transports water-insoluble substances such as bilirubin, hormones, fatty acids and drugs

Question 6

what cagoulation factors does the liver produce

Answer 6

factor II, VII, IX and X

protein C and S

Question 7

what are the protective liver cells

Answer 7

Kupffer

Question 8

what do Kupffer cells do

Answer 8

digest/destroy cellular debris and invading bacteria

Question 9

what happens to bile between meals

Answer 9

stored and conc in gall bladder

Question 10

what is the sphincter of Oddi like between meals

Answer 10

closed

Question 11

during a meal what happens to gall bladder

Answer 11

chyme in duodenum stimulates gall bladder smooth muscle to contract via CCK and vagal impulses

Question 12

during a meal what is sphincter of Oddi like

Answer 12

opens via CCK

Question 13

what happens to bile during meal

Answer 13

spurts into duodenum via cystic duct and common bile duct

Question 14

what does bile participate in

Answer 14

the digestion and absorption of fats

Question 15

what is the composition bile

Answer 15

bile acids cholic and chenodeoxycholic acids form bile salts with Na and K

bilirubin

IgA

cholesterol

phospholipids and lipids

Question 16

what is another name for gallstones

Answer 16

cholelithiasis

Question 17

what is the best surgery for symptomatic gallstones

Answer 17

laparoscopic cholecystectomy

Question 18

what drug can be given for gallstones

Answer 18

ursodeoxycholic acid

Question 19

what are the indications for ursodeoxycholic acid

Answer 19

small or mediums sized stones unimpaired gall bladder function

Question 20

what is biliary colic

Answer 20

pain due to gallstone temporarily blocking the bile duct

Question 21

what are the analgesic options for biliary colic

Answer 21

morphine buprenorphine or pethidine

Question 22

why is morphine preferred

Answer 22

Although morphine causes sphincter of Oddi to contract more it is a better analgesia and not contraindicated

Question 23

what drugs would you use to relive biliary spasm

Answer 23

atropine and GTN

Question 24

what happens to 5% of bile salts entering duodenum

Answer 24

lost in faeces

Question 25

what happens to most of the bile salts entering duodenum

Answer 25

reabsorbed in the terminal ileum and undergo enterohepatic recycling

Question 26

explain bile acid sequestrant mechanism

Answer 26

Trap the bile salts in the intestine, increasing their excretion resulting in more cholesterol to be converted to bile salts by interrupting enterohepatic recycling. Prevent the reabsorption of bile salts. The fall in hepatocyte cholesterol concentration causes compensatory increase in HMG CoA reductase activity and the number of LDL receptors (main mechanism in which they lower cholesterol).

Question 27

adverse effects of bile acid sequestrants

Answer 27

are confined to the gut, because the resins are not absorbed; these effects include bloating, abdominal discomfort, diarrhoea and constipation.

Question 28

bile acid sequestrates are use in

Answer 28

hyperlipidaemia and choelstatic jaundice

Question 29

what size of dose required

Answer 29

large

Question 30

bile acid sequestrates can cause deficient of what

Answer 30

fat soluble vitamins

Question 31

what drugs have unchanged activity during metabolism

Answer 31

diazepam to nordiazepam

Question 32

compare aspirin and its metabolites activity

Answer 32

aspirin - anti inflammatory and anti platelet metabolite - anti inflammatory

Question 33

what is the name of aspirins metabolite

Answer 33

salicylate acid

Question 34

name some reactions that happen in phase 1 of drug metabolism in liver

Answer 34

oxidation hydrolysis reduction

Question 35

name some reactions that happen in phase 2 of drug metabolism in liver

Answer 35

conjugation

Question 36

what do the CYP450 family of monooxygenases do

Answer 36

mediate oxidation reactions (phase 1) of many lipid soluble drugs in the liver

Question 37

what is hepatic encephalopathy

Answer 37

the occurrence of confusion, altered level of consciousness, and coma as a result of liver failure

Question 38

explain hepatic encephalopathy pathophysiology

Answer 38

- liver fails - nitrogenous waste builds up as ammonia in the circulation - passes t brain - cleared by astrocytes - excess glutamine causes an osmotic imbalance and a shift of fluid into these cells - cerebral oedema

Question 39

hepatic encephalopathy - treatment

Answer 39

lactulose

Question 40

lactulose is what type of laxative

Answer 40

osmotic

Question 41

lactulose effects

Answer 41

retain water - inc bulk - inc peristalsis

Question 42

antibiotics used in hepatic encephalopathy

Answer 42

neomycin rifaximin