Background: In patients undergoing hemodialysis or hemofiltration will suffer from the injury of reactive oxidative species. Oxidative stress will affect cell membrane, protein, and DNA. It will damage the cell and result in organ dysfunction. We believe that in patients, who have acute hepatic failure, undergoing plasma exchange or Molecular Absorbent Recirculating System for bridge therapy will suffer from the injury of reactive oxidative species, too. It will damage the kidney, lung, cerebral cortex, and other organs. It may result in death before the recovery of liver function or undergoing liver transplantation.

Aims: 1. Investigate the severity of oxidative stress and risk factors of high oxidative stress in acute hepatic failure patient undergoing plasma exchange or Molecular Absorbent Recirculating System. 2. Investigate the microcirculation status and risk factors in acute hepatic failure patient undergoing plasma exchange or Molecular Absorbent Recirculating System. 3. Study the relationship between oxidative stress and microcirculation status. 4. Study the correlation between oxidative stress and prognosis. 5. Study the correlation between microcirculation status and prognosis.

Inclusion Criteria:

1. Age > 18 years old
2. Patients with acute deterioration on Chronic liver failure, who required liver support treamtment
3. Patients with acute liver failure due to acute hepatitis, who reauired liver support treatment
4. Patients with acute liver dysfunction within 7 days after liver transplantation, who required liver support treatment

Exclusion Criteria:

1. Age > 70 years old
2. Cancer, not curable
3. Patients who had used of antioxidant therapy within 24 hours before study
4. Patients who had received hyperbaric oxygen therapy within 24 hours before study
5. Patients who had received peroxide treatment within 24 hours before study

Patients require liver support treatment