Propranolol therapy in thyrotoxicosis. A review of 84 patients undergoing surgery.

The effect of propranolol on the surgical course of 84 thyrotoxic patients undergoing partial thyroidectomy or extrathyroidal surgery was evaluated. Seventy-two patients (group 1) underwent surgery with propranolol as their sole preparatory medication, whereas in 12 (group 2) surgery was carried out after a rather prolonged period of thionamide preparation with the addition of propranolol preoperatively as an adjunctive therapeutic agent. Preoperative pulse rate and systolic blood pressure levels fell in both groups, and the clinical features of thyrotoxicosis were rapidly ameliorated with an average dose of propranolol of 330 mg (range 40 to 1,280 mg) daily. Maximal clinical response occurred within 48 to 72 hours of starting propranolol therapy. In 14 patients in group 1, paired serum calcium levels were reduced by the administration of propranolol preoperatively; serum thyroxine levels were unchanged. Serum thyroxine decay, evaluated postoperatively in the patients in group 1, was decreased. The half life of thyroxine was inversely related to the initial thyroxine levels. Analysis of these data indicates that the administration of propranolol alone provides rapid, safe and effective preparation of thyrotoxic patients for emergency or for elective thyroidal or extrathyroidal surgical procedures.