Ascites

Question 1

Define

Answer 1

Accumulation of free fluid within the peritoneal cavity

Question 2

% survival within 5 years of onset

Answer 2

10-20%

poor prognosis

Question 3

Ascites is common from what

Answer 3

Post-operation

Complication of cirrhosis

Question 4

*Main causes

Answer 4

Local inflammation
Low protein (inability to pull fluid back into intravascular space by osmosis)
Low flow (fluid can't move forwards through system e.g. due to a clot)

Question 5

When would local inflammation cause ascites

Answer 5

Peritonitis
Intra-abdominal surgery (post)
Abdominal cancers (ovarian)
Infection (TB)

Question 6

When would you see low protein

Answer 6

Hypoalbumineamia
Nephrotic syndrome
Malnutrition

Question 7

When would you see low flow (and ascites resulting)?

Answer 7

Cirrhosis (portal hypertension)
Budd-chiari syndrome (occlusion of hepatic veins that drain liver)
Cardiac failure
Constrictive pericarditis

Question 8

Risk factors

Answer 8

High sodium diet
Hepatocellular carcinoma
Splanchnic vein thrombosis, resulting in portal hypertension

Question 9

Clinical presentation

Answer 9

• Abdominal swelling (develop over days or wks)
• Distended abdomen
• Fullness in the flanks and SHIFTING DULLNESS
• Mild abdominal pain and discomfort
• Respiratory distress and difficulty eating
• Scratch marks on abdomen (caused by itching due to jaundice i.e. liver failure)
• Peripheral oedema

Question 10

Why is shifting dullness important in presentation

Answer 10

confirms the presence of fluid

Question 11

Diagnosis

Answer 11

• Shifting dullness
• Diagnostic aspiration of 10-20ml of fluid using Ascitic Tap
• Protein measurement of ascitic fluid from ascitic tap (transudate or exudate)

Question 12

What would be done with (diagnostic) aspiration of fluid using ascitic tap

Answer 12

Check for Raised white cell count (bacterial peritonitis)
Gram stain and culture
Cytology and malignancy
Amylase to exclude pancreatic ascites

Question 13

Protein measurement of ascitic fluid from ascitic tap: what is meant by transudate

Answer 13

Low protein (<30g/L)

Question 14

Protein measurement of ascitic fluid from ascitic tap: causes of transudate

Answer 14

• Portal hypertension e.g. cirrhosis
• Constrictive pericarditis
• Cardiac failure
• Budd-Chiari syndrome

Question 15

Protein measurement of ascitic fluid from ascitic tap: what is meant by exudate

Answer 15

High protein (>30g/L)

Question 16

Protein measurement of ascitic fluid from ascitic tap: causes of exudate

Answer 16

• Malignancy
• Peritonitis
• Pancreatitis
• Peritoneal tuberculosis
• Nephrotic syndrome

Question 17

Treatment

Answer 17

• Treat underlying cause
• Increase renal sodium excretion (or reduce sodium)
• Drain fluid (paracentesis) - can drain 5 litres at a time, used to relieve symptomatic tense ascites
• Transjugular Intraheptic Portosytemic Shunt (for resistant ascites, risky)

Question 18

Treatment - what diuretic should be given

Answer 18

Aldosterone antagonist e.g. oral spirolactone

since it spares K+

Question 19

Describe how ascites results from cirrhosis

Answer 19

In cirrhosis -> peripheral arterial vasodilation (controlled by NO, other vasodilators) -> reduction in effective blood volume
Activation of sympathetic nervous system and RAAS, promoting salt and fluid retention
Oedema formation is encouraged by hypoalbuminaemia and mainly localised to peritoneal cavity due to portal hypertension.

Question 20

What increased hydrostatic pressure in ascites

Answer 20

Portal hypertension

RAAS activation

Question 21

What causes oedema in ascites

Answer 21

Oncotic pressure decreases in liver cirrhosis due to hypoalbuminaemia
Hydrostatic pressure > oncotic pressure

Question 22

Ascites signs

Answer 22

Distended abdomen

Shifting dullness

Question 23

Investigations

Answer 23

Ascitic tap = culture, gram stain, cytology, protein

Question 24

Management

Answer 24

Restrict fluid and sodium
Spironolactone
Treat underlying cause

Question 25

Appearance of transudate vs Exudate

Answer 25

Transudate = clear
Exudate = Cloudy

Question 26

Albumin level in Transudate vs Exudate

Answer 26

Transudate: 11g/L or more below serum albumin
Exudate: <11g/L below the serum albumin