The perioperative course of 44
hyperthyroid patients prepared for surgery with
propranolol alone, including 11 with severe
thyrotoxicosis was compared to that of 20 euthyroid patients prepared for surgery with
carbimazole. Conventional
propranolol at a dosage of 160 mg/day was frequently insufficient to produce a high degree of beta-
adrenergic blockade, particularly in severely thyrotoxic patients. A greater than 25 per cent reduction in sitting pulse rate was associated with a high degree of beta-blockade. The
clinical course of patients with mild or moderate
thyrotoxicosis was similar to that of the patients prepared with
carbimazole. In contrast, the course of severely thyrotoxic patients was complicated and, in addition to a higher preoperative
propranolol dosage, these patients commonly required supplemental
propranolol after operation. Although
thyroid crisis did not occur in any patient, we cannot recommend the use of
propranolol alone for the severely thyrotoxic patient.