Peri-operative oral triiodothyronine replacement therapy to prevent postoperative low triiodothyronine state following valvular heart surgery.

This study evaluated the effect of oral triiodothyronine (T(3)) replacement therapy, starting on the day of the surgery, on thyroid hormone concentrations and clinical outcome in high-risk patients undergoing valvular heart surgery. Fifty patients were randomly allocated to either T(3) or placebo. In the treatment (T(3)) group patients received 20 microg of oral or nasogastric T(3) every 12 h starting just before induction of anaesthesia and until the first day after surgery. T(3) concentrations were significantly higher in the T(3) group than the placebo group from 1 to 36 h after removal of the aortic cross clamp. The number of patients requiring vasopressin after discontinuing cardiopulmonary bypass was significantly greater in the placebo group than the T(3) group. Significantly fewer patients required vasopressors in the T(3) group on the first day after surgery.