Unit 4 - The liver Flashcards

1
Q

What is the largest internal organ of the body?

A

The liver

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

What percentage of resting cardiac output is delivered to the liver?

A

30%

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

What percentage of total blood volume is held in the liver?

A

13%

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

What unique feature does the liver have?

A

Regenerative

- can regenerate to within 5 - 10% of its original size

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

What is the functional unit of the liver?

A

Hepatocyte
the major parenchymal cells in the liver, play pivotal roles in metabolism, detoxification, and protein synthesis. Hepatocytes also activate innate immunity against invading microorganisms by secreting innate immunity proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How are hepatocytes arranged in the liver?

A

In lobules

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

What percentage of the blood delivered to the liver is delivered via the hepatic portal vein?

A

70%

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

What percentage of the blood delivered to the liver is delivered via the hepatic artery?

A

30%

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

Which vessel takes blood away from the liver?

A

Hepatic vein

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

What makes up the portal triad?

A
  • hepatic artery
  • hepatic portal vein
  • bile duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a sinusoid?

A

Capillary space in the liver between hepatocytes

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

What is the function of the sinusoid?

A

Blood delivered to the sinusoid is exposed to the hepatocytes

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

What is the function of the liver?

A
  • storage
  • clearance
  • filtration
  • secretion
  • excretion
  • synthesis
  • metabolism
  • homeostasis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does the liver carry out detoxification?

A
Destroys endogenous and exogenous substances
- metabolism
Destroys cellular debris and invading bacteria
- phagocytosis
Deamination of amino acids
Removal of bilirubin
- build up would lead to jaundice
Hormone deactivation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the two classifications of liver disease?

A
  • acute

- chronic

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

What are the characteristics of acute liver disease?

A
Less than 6 months duration
Often involves spontaneously
- self limiting
Rapid decline in liver function
May be asymptomatic
100% association with encephalopathy and coagulopathy
Can result in acute liver failure (ALF)
17
Q

What are the characteristics of chronic liver disease?

A
Over 6 months duration
Often symptomatic
Secondary to long-standing cell damage
Permanent structure change
Loss of normal liver architecture
Cirrhosis
- fibrous scars
- divides the liver in nodulesWhat
18
Q

What are the causes of liver disease?

A
  • viral infection
  • alcohol
  • non-alcoholic fatty liver disease
  • non-alcoholic steatohepatitis
  • cholestasis
  • intra-hepatic (in liver)
  • extra-hepatic (related to pancreas)
  • immune disorders
  • vascular abnormalities
  • metabolic disorders
  • genetic disorders
  • drugs
19
Q

What five viruses are responsible for liver disease?

A

Hep A - faecal contamination of food or drink

Hep B - blood/blood contamination

Hep C - blood/blood contamination

Hep D - have to have Hep B to get Hep D

Hep E - faecal contamination of food or drink

20
Q

What is the route of infection for hepatitis A and E?

A

Faecal contamination of food or drink

21
Q

What is the single most significant cause of liver disease in the Western world?

A

Alcohol consumption

22
Q

How does alcohol cause liver disease?

A

Fibrous tissue in liver increases resistance to blood flow from the portal system resulting in portal hypertension (PHT)
As liver cell death continues it leads to liver failure
Rate of progression (and regression) linked to further alcohol consumption
- eventually leads to cirrhosis (scar tissue)

23
Q

What is non-alcoholic fatty liver disease (NAFLD)?

A

Damage caused by fat in the diet

24
Q

What is non-alcoholic steatohepatitis (NASH)?

A

An advanced form of non-alcoholic fatty liver disease (NAFLD)

  • NAFLD is caused by build up of fat in the liver
  • when this build up causes inflammation and damage, it is known as NASH, which can lead to scarring of the liver
25
Q

What is cholestasis?

A

Blockage of bile release

26
Q

What are the two types of liver disease caused by drugs?

A

Type A

Type B

27
Q

What is Type A drug damage to the liver?

A

Dose related

  • withdrawal of precipitating drug results in reversal
  • paracetamol
  • tetracyclines
  • methotrexate
28
Q

What is Type B drug damage to the liver?

A
Idiosyncratic
- bizarre!
Hypersensitivity or metabolic
- not related to dose
- just exposed to drug
29
Q

How has liver mortality changed since 1970?

A

Increased by 500%

30
Q

How has alcohol-related hospital admissions (specifically liver admissions) changed between 2002 - 2012?

A

Doubled

31
Q

What are the symptoms of liver disease?

A
Non specific symptoms
- weakness
- fatigue
- general malaise
Poor nutrition status
- chronic
- weight loss
- anorexia
- advanced
- loss of muscle bulk
Abdominal discomfort/pain
Tenderness over liver
- upper right quadrant
Jaundice
- yellowing of skin and sclera
32
Q

What are the cutaneous signs of liver disease?

A
Hyperpigmentation
- darker patches of skin
Scratch marks
- itchy
Spider naevi
- surface vessels
Non specific
- palmar erythema
- red palms
- Dupuytren's contracture
- involuntary contracture of fingers to palms
- nail changes
- finger clubbing
33
Q

What are the abdominal signs of liver disease?

A
Distension
Hepatomegaly
- enlargement of liver
Splenomegaly
- enlargement of spleen
Umbilical and paraumbilical veins
- greeny/blue veins under surface of skin
34
Q

What are the symptoms of jaundice?

A

Yellowing of the skin and sclerae

- sudden onset in adults should be investigated urgently

35
Q

What are the causes of jaundice?

A
Hepatocellular
- drugs
- hepatitis
- tumour
Cholestatic
- obstruction of bile flow
- tumour
Prehepatic
- increased blood breakdown
36
Q

What causes pruritis (itching of the skin) associated with liver disease?

A

Deposition of bile salts in the skin
Concentration does not correlate with severity
- low concentrations can be very itchy!
Most debilitating in cholestatic conditions
- obstruction relieved by endoscopy, radiology, surgery
Pharmacological treatment favoured for other causes

37
Q

What are the signs of portal hypertension in liver disease?

A
Increased pressure in portal venous system leads to
- collateral vein formation
- leaky - risk of internal bleeding
- shunting of blood to systemic circulation
Contributes to
- formation of ascites
- development of encephalopathy
- build up of nitrogenous products in the brain
- altered awareness
- cognitive impairment
Complications
- variceal bleed
- internal bleeding
38
Q

What are the signs of ascites in liver disease?

A
Accumulation of fluid within the abdominal cavity
Caused by
- central hypovolaemia
- reduced serum albumin
- PHT and splenic artery vasodilation
39
Q

What are the signs of clotting abnormalities in liver disease?

A

Hepatocyte failure causes synthesis of defective clotting factors