Discussion: Artificial Organs

Abstract

Courtney opened the discussion by recalling the situation ten years ago with the interest then in the potential use of sorbents for detoxification and for replacing membrane dialysis with the possibility of producing smaller wearable artificial kidneys and liver support systems. The artificial kidney has not changed much in 40 years let alone 10 years. The same membranes are used in almost all dialysers. There was interest in heparinisation of membranes some 25 years ago and it would be good to think that by the 30th anniversary they might have found a clinical role. Ryan indicated that endotoxaemia was a problem in their approaches to the management of toxic shock, and they used a specific antibiotic polymyxin-B-sulphate bound to Sepharose beads. The results demonstrated that endotoxin could be removed from plasma, and that protection from endotoxin-mediated leukopenia and thrombocytopenia may be given. However, the systemic use of this antibiotic is limited because it is both neurotoxic and nephrotoxic, but by binding it to Sepharose there had been no elution problems. Gaylor in reply to Courtney expressed the view that composite membranes would be useful only if membrane lungs are to be used for long-term support; although microporous membrane devices have been reported to have much longer operation times, manufacturers recommend their use only for short-term surgical bypass operations of less than four hours’ duration.