A total of 32 studies (n=849) were included: 1 non-randomised open controlled trial, 5 cohort studies or prospective uncontrolled trials and 26 non-analytic studies (e.g. case series). Three case series (n=443) and 2 prospective uncontrolled trials (n=59) focused on abdominal paracentesis. One non-randomised open controlled trial (n=68), 3 cohort studies (n=43) and 1 case report (n=2) assessed management by diuretics. The non-randomised open controlled trial (n=42) and 21 case series (n=592) assessed management by peritoneovenous shunts.
Symptomatic management by paracentesis.
Three studies show good, although temporary, relief of symptoms related to the build-up of fluid for about 90% of patients managed by paracentesis. There was no consensus on fluid withdrawal speed. Possible complications of paracentesis included secondary peritonitis, pulmonary emboli and hypotension. Repeated large-volume paracentesis without plasma volume expansion may be associated with a significantly higher incidence of hypotension and renal impairment. A significant improvement of symptoms of abdominal pressure occurred with the removal of a few litres (mean 5.3 L, range: 0.8 to 15) without severe side-effects (data based on 1 study).
Symptomatic management by diuretics.
Diuretic use in managing malignant ascites was inconsistent amongst physicians, and the available evidence assessing its efficacy was weak. However, overall, in patients with different tumours, diuretics seemed to be successful in approximately 43% of cases (data based on 5 studies). One study suggested that serum-ascites albumin gradients may provide a useful guide to predict a patient's response to diuretics.
Symptomatic management by peritoneovenous shunts.
Shunt insertion was associated with potential fatal side-effects and considerable costs in terms of time and money. For these reasons, shunts should only be used when other treatment options like diuretics have failed and when the life expectancy of the patient is long enough to derive benefit.