Acites

Question 1

What is an acite?

Answer 1

ascites is the non-physiologic accumulation of fluid in the peritoneum, most commonly secondary to liver disease or malignancy

Question 2

Give the three underlying pathophysiological mechanisms behind ascites:

Answer 2

1) sodium and water retention
2) portal hypertension
3) low serum albumin

Question 3

What are the 4 causes of acites?

Answer 3

Cirrhosis (75%)
Malignancy (10%)
Heart failure (3%)
TB (1%)

Question 4

What causes sodium and water retention in liver failure? (3)

Answer 4

1) in liver failure, there is decreased breakdown of peripheral arterial vasodilators such as nitric oxide, ANP and prostaglandins
2) this causes peripheral arterial vasodilation which reduces the effective blood volume of the body
3) this stimulates the sympathetic nervous system and the RAAS system to promote salt and water retention

Question 5

What two veins join to form the portal vein?

Answer 5

1) superior mesenteric
2) splanchnic

Question 6

Describe how portal hypertension can cause ascites:

Answer 6

Normally, the liver receives blood from the spleen and gastrointestinal organs via the portal vein. When fibrosis becomes extensive, it is harder for blood to flow through the liver. As a consequence, the blood coming from the portal vein may start to back up, leading to portal hypertension, which refers to increased blood pressure in the portal vein. As a result, fluid may start to leak out of the portal vein and into the abdomen, leading to ascites.

Question 7

Describe how low serum albumin can cause ascites:

Answer 7

it contributes to a reduced plasma oncotic pressure

Question 8

Why is there a low serum albumin in liver cirrhosis?

Answer 8

the liver produces albumin

Question 9

If there is severe abdominal pain associated with ascites, what is the likely diagnosis?

Answer 9

spontaneous bacterial peritonitis

Question 10

What is spontaneous bacterial peritonitis?

Answer 10

it is a bacterial infection of the ascitic fluid. If not caught and treated promptly, bacteria can enter the bloodstream and lead to sepsis. In turn, sepsis can trigger a systemic inflammatory response and circulatory dysfunction. The end-stage result is organ damage and failure, such as kidney failure, or the worsening of liver failure.

Question 11

What does acites look like?

Answer 11

The presentation of ascites can vary depending on its severity. Those with mild ascites may have an abdomen that appears normal, whereas those with more severe ascites may have a very large distended abdomen. As the fluid accumulates in the abdominal cavity. The belly button can also protrude from the body with severe ascites.

Question 12

What does acites feel like to a patient?

Answer 12

Ascites can put pressure within the abdomen, causing it to feel very large and tight. As the abdomen grows larger, the increased pressure on nearby organs may cause abdominal discomfort, lack of appetite, and shortness of breath.

Question 13

Give two findings on examination that support diagnosis of ascites:

Answer 13

1) positive shifting dullness
2) peripheral oedema

Question 14

Describe how to carry out the shifting dullness test:

Answer 14

percuss the abdomen to identify any dullness and then roll the patient towards you and percuss in this position to see if the dullness has shifted to an area of prior tympany

Question 15

Name three laboratory investigations for ascites:

Answer 15

an aspiration of peritoneal fluid should be obtained for:
1) cell count (neutrophil levels for bacterial peritonitis)
2) gram stain and culture
3) protein measurement (serum-ascites albumin gradient)

Question 16

What are the risk factors for acites?

Answer 16

portal hypertension:
cirrhosis (most common)
alcoholic hepatitis
heart failure
IVC obstruction
Budd-Chiari syndrome

malignancy
hypoalbuminemia
nephrotic syndrome
enteropathy
malnutrition
infections
peritoneal tuberculosis

Question 17

What are the common symptoms of acites?

Answer 17

abdominal pain
rapid weight gain
early satiety

Question 18

What may be seen on physical examination?

Answer 18

distended abdomen
peripheral oedema
may see signs of liver disease
spider angiomata
palmar erythema
gynecomastia
hepatomegaly
jaundice
may see signs of heart failure
jugular venous distention

Question 19

What is the protein measurement unit when analysing peritoneal fluid in ascites?

Answer 19

serum-ascites albumin gradient

Question 20

What does a serum-ascites albumin gradient higher than 11g/L indicate in ascites?

Answer 20

it is caused by portal hypertension..

Question 21

What does a serum-ascites albumin gradient lower than 11g/L indicate in ascites?

Answer 21

it is caused by a non-liver cause such as pancreatitis or cancer

Question 22

Give three conditions associated with straw-coloured ascites fluid:

Answer 22

1) cirrhosis
2) malignancy
3) infection

Question 23

Give a condition associated with chylous ascites fluid:

Answer 23

obstruction of the main lymphatic duct

Question 24

Give three conditions associated with haemorrhagic ascites fluid:

Answer 24

1) ruptured ectopic pregnancy
2) pancreatitis
3) abdominal trauma

Question 25

Give 4 ways in which ascites patients can reduce sodium intake and increase renal Na+ excretion (to produce a net reabsorption of fluid):

Answer 25

1) restrict dietary sodium
2) avoid Na+ retaining or Na+ rich drugs
3) fluid restriction
4) diuretics

Question 26

What diuretic is given for ascites?

Answer 26

spironolactone (if no response, add furosemide)

Question 27

Name two classes of drugs rich in sodium:

Answer 27

1) antacids
2) antibiotics

Question 28

Name two Na+ retaining drugs?

Answer 28

1) NSAIDs
2) corticosteroids

Question 29

What is the name of the process that drains fluid from the peritoneal cavity?

Answer 29

paracentesis

Question 30

Give two instances where paracentesis is needed to treat ascites:

Answer 30

1) when a tense, painful ascites needs to be drained
2) diuretic therapy is insufficient

Question 31

Give two risk factors associated with paracentesis:

Answer 31

1) hypovolaemia
2) renal dysfunction
(due to an accentuation of arteriolar vasodilation)

Question 32

Name three shunts that can be used to treat ascites:

Answer 32

1) transjugular intrahepatic portosystemic shunt (TIPS)
2) peritoneo-bladder conduit
3) long-term abdominal drain

Question 33

Describe how a transjugular intrahepatic portosystemic shunt can treat resistant ascites:

Answer 33

it re-routes blood from the portal vein to the hepatic vein to reduce portal hypertension

Question 34

Describe how a peritoneal-bladder conduit can treat resistant ascites:

Answer 34

it removes ascites fluid from the peritoneal cavity into the urinary bladder through a surgical join