Changes in intracranial pressure during haemofiltration in oliguric patients with grade IV hepatic encephalopathy

Seven consecutive patients with grade IV hepatic encephalopathy, due to fulminant hepatic failure complicated by oliguric renal failure were allocated at random to treatment with daily machine haemofiltration (MHF) or continuous arteriovenous haemofiltration (CAVHF). Intracranial pressure (ICP) was continuously monitored using a subdural catheter. Four patients received 17 treatments by MHF, and ICP increased from 8.4 +/- 1.5 mm Hg (mean + SEM) prior to treatment to 12.6 +/- 1.8 mm Hg on completion (p less than 0.05). Active intervention was required on twenty occasions to treat sustained increases in ICP (greater than 25 mm Hg maintained for 5 min or longer). A total of 12 haemofilters were used in the treatment of 3 patients by CAVHF. The ICP showed greater stability during CAVHF therapy, the mean pressure prior to treatment was 15.6 +/- 5.2 mm Hg and fell to 11.7 +/- 2.3 mm Hg at 4 h. Sustained increases in ICP occurred in only 1 patient as a preterminal event. These findings suggest that CAVHF is the preferred method of treatment in patients with fulminant hepatic failure complicated by oliguric renal failure who are at risk of developing cerebral oedema.