Therapeutic properties.of haemodialysis and blood exchange transfusion in organophosphate poisoning.

Human blood was contaminated with nitrostigmine, dimethoate and demeton-S-methyl sulfoxide. It was then dialysed, concentrations of organophosphates were determined and dialysance values calculated. The influence of blood exchange transfusion on poison elimination as well as on the cholinesterase activity of blood, brain and muscle was studied in rats poisoned with nitrostigmine. Haemodialysis was found to be quite an effective method for eliminating demeton-S-methyl sulfoxide and dimethoate, dialysance values of 52.98 ml/min and 59.07 ml/min being found for demeton-S-methyl sulfoxide and dimethoate respectively. Nitrostigmine could not be removed by haemodialysis. These findings suggest that haemodialysis could be of therapeutic value in the treatment of severe demeton-S-methyl sulfoxide and dimethoate poisoning in man. By blood exchange transfusion only 0.06% of the injected dose of nitrostigmine could be removed from the body of poisoned rats. Acetylcholinesterase activity increased only briefly in the period of blood exchange transfusion and decreased gradually afterwards. The enzymatic activity of brain and muscle was unaffected. Therefore, blood exchange transfusion has, if any at all, only poor therapeutic properties in nitrostigmine intoxication.