Makindo Medical Notes

Available data suggests colloid/albumin replacement to prevent haemodynamic deterioration after paracentesis is not necessary. However, proceed slowly, draining at most 4-6 L over 4 hours or longer.

About Ascites

• Malignant Ascites refers to the accumulation of fluid in the peritoneal cavity related to a malignancy.
• Malignancy causes approximately 10% of all cases of ascites.
• Common in cancers such as breast, colorectal, endometrial, gastric, ovarian, and pancreatic cancers.

Aetiology

• Peritoneal lymphatic obstruction.
• Low albumin leading to reduced oncotic pressure.
• Increased capillary permeability.
• Increased portal vein pressure with activation of the renin-angiotensin-aldosterone (RAA) system.

Clinical Presentation

• Symptoms include abdominal bloating, swelling, pain, nausea, and vomiting.
• Other symptoms: anorexia, fatigue, peripheral oedema, heartburn, and dyspnoea.

Cautions for Paracentesis

• Coagulopathy: raised INR > 1.5 and low platelets < 40x10⁹/L.
• Hyponatraemia < 126 mmol/L.
• Poor renal function, hepatic impairment.
• Significant anaemia, albumin < 20 g/L.
• Neutropenia or immune deficiency.

Contraindications

• Local or systemic infection.
• Coagulopathy: platelets < 40x10⁹/L or INR > 1.4.
• Limit paracentesis to 4-6 litres maximum if: hepatic or renal failure (creatinine > 250 mmol/L) or albumin < 30 g/L or sodium < 125 mmol/L.

Investigations

• Blood tests: FBC, U&Es, LFTs, and coagulation screen. Monitor U&Es daily during paracentesis.
• Send ascitic fluid for microscopy and culture. Measure serum-to-ascites albumin gradient, total protein, glucose, LDH, and cytology.
• Check for bacterial infections, particularly in patients with fever or abdominal pain.
• Avoid serum CA125 testing as it is often falsely elevated in the presence of ascites.

Management

• Malignant ascites carries a poor prognosis, and treatment should focus on patient comfort and quality of life.
• Options include diuretic therapy, therapeutic paracentesis, and peritoneovenous shunts.
• Consider Spironolactone 100-400 mg/day. Note that it can take 5 days to respond and may cause side effects like nausea, hyperkalaemia, and hyponatraemia.
• Therapeutic Paracentesis: Removal of 4-6 litres can provide symptomatic relief but avoid draining more to reduce the risk of hypovolemia.
• Albumin infusions are not necessary during or after paracentesis for malignant ascites.

References

• Paracentesis for Malignant Ascites Procedure
• Guidelines for the Management of Malignant Ascites
• Guidelines for the Management of Malignant Ascites in Palliative Care