Cerebral Blood Flow Velocity during High Volume Plasmapheresis in Fulminant Hepatic Failure

High volume plasmapheresis has previousy been found to improve neurological statuses in patients with fulminant hepatic failure. We investigated the relationship between the neurological status and cerebral blood flow velocity (V_mean) during high volume plasmapheresis in 18 consecutive patients (ten females and eight males) with fulminant hepatic failure, with a mean age of 43 (range 9 to 57) years. The mean arterial pressure (MAP) and intracranial pressure (ICP) were also recorded. A total of 16% of body weight was exchanged with fresh frozen plasma per day. Thirty-six plasma exchanges were performed with a median of 2 (range 1 to 8) per patient. Eleven of the patients survived (61%), nine after liver transplantation. Following the first high volume plasmapheresis, the coma score improved from 6 (1-8) to 2 (0-8) (p < 0.05), V_mean increased from 40 (14-152) to 62 (16-186) cm S⁻¹ (p < 0.05), and MAP from 72 (35-118) to 94 (47-138) mmHg (p < 0.05). The intracranial pressure (ICP) was monitored and remained unchanged in nine patients whereas the cerebral perfusion pressure (MAP minus ICP) increased in the surviving group from 55 (40-74) to 80 (50-91) mmHg (p = 0.07) in contrast to no changes in the non survival group. In conclusion this study suggests that the neurological status, may improve during high volume plasmapheresis as MAP and V_mean increase the cerebral oxygen delivery.