Thyroid storm treatment with blood exchange and plasmapheresis.

Conventional therapy for hyperthyroidism is designed to reduce the rate of thyroid hormone release from the gland and also to ameliorate the effects on the tissues and consists of iodine, antithyroid drugs, adrenergic blocking drugs, and corticosteroids. Because of the long half-life of thyroxine in the serum these measures cannot produce a sharp decrease in the very high level of circulating thyroid hormone. Plasmapheresis was effective in removing a substantial quantity of hormone from a dog in a hyperthyroid-like state and reduced serum thyroxine levels to 40% of the initial value. A striking improvement was observed in three patients after the use of blood exchange or plasmapheresis procedures when death appeared imminent despite conventional therapy for thyrotoxic crisis.