Malignant ascites in palliative care
Many abdominal and pelvic cancers, and some nonmalignant disorders, cause ascites in patients with a life-limiting illness. For management of nonmalignant ascites, see the Liver disorders guidelines. Malignant ascites indicates an advanced stage of disease; however, some patients with malignant ascites may still respond to chemotherapy. Management of ascites depends on the cause, and is guided by the potential benefits and burdens of treatment, and the patient’s prognosis, preferences and goals of care—see Principles of symptom management in palliative care.
Ascites can be treated with abdominal paracentesis when distension causes discomfort or compromises diaphragmatic movement. Up to 4 litres of fluid per day should be drained slowly over a few hours to avoid compromise to the circulating blood volume or the need for intravenous albumin replacement. The procedure usually needs to be repeated as ascitic fluid may reaccumulate quickly. Frequent drainage may exacerbate protein loss; however, there is little evidence that parenteral albumin or dexamethasone is useful to reduce intravascular depletion or reduce re-accumulation of ascites in patients with malignant ascites.
A semipermanent peritoneal (pigtail), tunnelled drain catheter or intraperitoneal port can be used if frequent drainage of malignant ascites is required. Insertion of a semipermanent drain should be considered to avoid the burden of repeated hospitalisations, if a patient’s prognosis suggests longer survival is likely.
Although diuretics reduce the accumulation of nonmalignant ascites, they may be less beneficial in malignant ascites. If a trial of diuretics is considered, use:
spironolactone 50 mg to 100 mg orally, daily. If needed and tolerated, increase dose by 100 mg daily every 4 to 7 days, to a maximum of 400 mg daily spironolactone
PLUS (if needed)
furosemide (frusemide) 40 mg orally, daily. If needed and tolerated, increase dose by 40 mg daily every 4 to 7 days, to a maximum of 160 mg daily. furosemide (frusemide)
For spironolactone, start with a dose of 50 mg in patients who are at risk of dehydration or electrolyte disturbance.
Diuretics can increase thirst and contribute to postural hypotension and increase the risk of falls. They can also cause hyponatraemia, changes in potassium concentration, and kidney impairment; monitor electrolytes and kidney function, if compatible with the patient’s goals of care.