Study of hepatic venous wedge and intraperitoneal pressures in cirrhotic patients with refractory ascites treated by dialytic ultrafiltration.

Three cirrhotic patients with intractable ascites and one patient with malignant ascites received dialytic ultrafiltration of ascitic fluid by a haemofilter system for symptomatic relief. The haemofilter removes fluid and substances with a molecular weight less than 50,000 daltons and the concentrated ascitic fluid was reinfused into the peritoneal cavity after ultrafiltration. The changes in intraperitoneal and hepatic venous wedge pressures were studied in these patients. Dialytic ultrafiltration of ascites was associated with a parallel fall of both intraperitoneal and hepatic venous wedge pressures in cirrhotic patients but not in the patient with malignant ascites. The intraperitoneal and hepatic venous wedge pressure remained low for 18 h after completion of dialytic ultrafiltration. The mean arterial pressure and central venous pressure remained unchanged despite rapid removal of ascitic fluid. The interrelationships between the intraperitoneal pressure, hepatic venous wedge pressure, and vascular volume are discussed.