Heterologous extracorporeal hepatic support: Haemodynamic, biochemical, and immunological observations

Abstract

IN an attempt to provide an experimental appraisal of the value and limitations of extracorporeal heterologous liver perfusion as a method of temporary hepatic support, each of 4 normal calves was connected to a pig liver on two separate occasions at an interval of 1–3 weeks. With the technique employed these perfusions were tolerated for 6–7 hours. Acute liver failure was induced in another group of 5 calves by carrying out a portacaval anastomosis followed by ligation of the hepatic artery. Three of these animals were treated by repeated pig-liver perfusions. Survival was prolonged in 2 as compared with untreated controls, and the third made a complete recovery. Porcine protein was detected in all the calves after perfusion but antibody to this protein was only detected in 2 calves. Skin-grafts taken from the liver-donor pig during the second or third perfusion were accepted by the recipient calves for much longer periods than did unperfused animals. When 3 long-term surviving calves were challenged with intravenous porcine plasma only mild and transient reactions were seen. It is suggested that extracorporeal liver perfusion is beneficial, it is relatively free from immunological reactions, and that this procedure appears to confer on the recipients some degree of immunological tolerance.