[Plasmapheresis in the elimination of toxic substances with marked plasma protein-binding properties (author's...

Plasmapheresis is a method used to eliminate toxic substances with high plasma protein-binding properties. Poisoning by strongly plasma protein-binding substances cannot be treated by haemodialysis or peritoneal dialysis. Hence, an attempt was made to hasten the elimination of phenylbutazone, a suitable model substance (plasma protein binding affinity 98%), by plasmapheresis. Some of the experiments were performed with oxygen under high pressure (OHP). A singly plasmapheresis of the total blood volume or triple plasmapheresis of half of the blood volume, performed at 20 min intervals accelerated the elimination of phenylbutazone significantly and all animals survived. A single plasmapheresis of the threefold blood volume had the greatest effect in lowering the concentration of phenylbutazone in the blood, but only one of three animals survived. OHP had no influence on the half-life of phenylbutazone and did not increase the survival rate.