liver Flashcards

1
Q

what vessels supply blood to the liver

A
  • hepatic artery - branch of the coeliac axis (25%)

- portal vein - drains most of the GI tract and spleen (75%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the network between hepatocytes

A

bile canaliculi which join to form thin bile ductules near the portal tract which in turn enter bile ducts in the portal tracts

  • the hepatic ducts join at the porta hepatitis to form the common hepatic duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what connects the gall bladder to the lower end of the common hepatic duct

A

cystic duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does the gallbladder store

A

It lies under the right lobe of the liver and stores and concentrates hepatic bile - it has a capacity of 50ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what forms the central bile duct

A

cystic and hepatic ducts, narrowing at its distal end to pass into the duodenum

  • the CBD and pancreatic duct open into the 2nd part of the duodenum through a common channel at the ampulla of vater
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

where is the liver found

A

the right hyporchondrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how many segments make up the liver

A

8 - each segment has its own portal pedicle, permitting individual resection at surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are sinusoids

A

low pressure vascular channels that receive blood from terminal branches of the hepatic artery and portal vein at the periphery of lobules and deliver it into central veins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the caudate lobe

A

independent part of the liver, supplied by the right and left hepatic artery and portal vein. Blood from the caudate lobe drains directly into the vena cava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the acinus

A

the functional hepatic unit which consists of parynchyma supplied by teh smallest portal tracts containing portal vein radicals, hepatic arterioles and bile ductules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is jaundice

A

Jaundice is a condition in which the skin, whites of the eyes and mucous membranes turn yellow because of a high level of bilirubin, a yellow-orange bile pigment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

when is jaundice detectable clinically

A

when serum bilirubin is over 50 umol/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what can jaundice be divided into

A
  • haemolytic jaundice
  • congenital hyperbilirubinaemia
  • cholestatic jaundice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is haemolytic jaundice

A

Increased bilirubin load for the liver cells due to increased breakdown of RBCs

  • usually mild jaundice
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what causes haemolytic jaundice

A

Haemolytic anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

clinical features of haemolytic jaundice

A
  • jaundice
  • splenomegaly
  • gallstones
  • leg ulcers
17
Q

what is congenital hyperbilirubinaemia

A

defects in conjugation

18
Q

what is unconjugated bilirubin

A

not water soluble and therefore doesn’t pass into the urine

Acholuric jaundice = Jaundice without bile pigments in the urine.

19
Q

what are unconjugated types of jaundice

A
  • Gilberts syndrome

- Crigler-Najjar syndrome

20
Q

what are conjugated types of jaundice

A
  • Dubin-Johnson and Rotors syndromes
  • Benign recurrent intrahepatic cholestasis
  • Progressive familial intrahepatic cholestasis syndromes
21
Q

what is cholestatic jaundice (acquired)

A

cholestatic, or obstructive, jaundice, occurs when essentially normal liver cells are unable to transport bilirubin either through the hepatic-bile capillary membrane, because of damage in that area, or through the biliary tract, because of anatomical obstructions such as gallstones or cancer.

22
Q

what is extra hepatic cholestasis

A

due to a large duct obstruction of bile flow at ant point in the biliary tract distal to the bile canaliculi

23
Q

what is intra hepatic cholestasis

A

occurs because of the failure of bile secretion, which may be caused by intrinsic defects in bile secretion of inflammation in the intrahepatic ducts

24
Q

what causes extra hepatic cholestasis

A
  • common duct stones
  • Carcinoma in the bile duct, head of pancreas or ampulla
  • Biliary stricture
  • Sclerosing cholangitis
  • Pancreatic pseudocyst
25
Q

what causes intra hepatic cholestasis

A
  • viral hepatitis
  • drugs
  • alcohol
  • cirrhosis
  • autoimmune cholangitis
26
Q

what are the signs and symptoms of extra and intra hepatic cholestasis

A
  • jaundice
  • pale stools
  • dark urine
  • serum bilirubin is conjugated
27
Q

what are the 2 most useful tests for jaundice

A
  • viral markers ( for HAV, HBV, HCV )
  • ultrasound - to exclude an extra hepatic obstruction and to diagnose any features comparable with chronic liver disease
28
Q

what is acute liver failure

A

acute liver injury with encephalopathy and deranged coagulation (INR>1.5) in a patient with a previously normal liver

29
Q

what causes acute liver failure

A
  • viruses
  • drugs eg paracetamol, antibiotics, antidepressants
  • toxins
  • hepatic failure in pregnancy
  • vascular causes
  • metabolic causes
  • malignancies
30
Q

what are clinical features of acute liver failure

A
  • jaundice
  • small liver
  • signs of hepatic encephalopathy
  • Fetor hepaticus
  • fever
  • vomitting
  • hypotension
  • hypoglycaemia
  • spascitiy
  • cerebral oedema
31
Q

what investigations should be carried out for acute liver failure

A
  • routine tests
  • there is hyperbilirubunaemia, high serum aminotransferases and low levels of coagulation factors . Aminotransferases are not useful indicators of the course of the disease as they tend to fall along with the albumin with progressive liver damage
  • an electroencephalogram is sometimes helpful in grading encepathology
  • ultrasound will define size of liver and may indicate underlying liver pathology
32
Q

management of acute liver failure

A
  • no specific treatment
  • supportive therapy
  • 20% mannitol if increased intracranial pressure
  • suspected infection = antibiotics
  • transplant
33
Q

what is autoimmune hepatitis

A

Inflammatory liver disease of unknown cause characterized by suppressor T cell defects with autoantibodies directed against hepatocyte surface antigens. Type 2: children and young adults, type 1: adults

34
Q

signs and symptoms of autoimmune hepatitis

A

Most present with autoimmune signs: fever, malaise, urticarial rash, polyarthritis, pleurisy, pulmonary infiltration or glomerulonephritis. Also may present with signs of chronic liver disease

35
Q

what are investigation findings for autoimmune hepatitis

A

Raised AST, ALT, serum bilirubin and Alk Phos, hyper gammaglobulinaemia (esp IgG), positive autoantibodies

36
Q

how to manage autoimmune hepatitis

A
  • prednisolone daily for at least 2 weeks followed by a slow reduction to a maintenance dose
  • Azathrhioprine should be added as a steroid sparing agent