Effects of Enflurane Anesthesia and Surgery on Thyroid Function / 대한마취과학회지

ABSTRACT

This study was performed to investigate the effects of enflurane anesthesia and surgery on thyroid function by determining the plasma concentration of thyroxid(T4) and trilodothyronine(T3) in 10 patients who had neither hepatic disorder nor endocrine disease. Each patient was premedicated with diazepam 10mg and atropine sulfate 0.5mg intramuscularly one hour before induction of anesthesia. Anesthesia was induced with pentohal sodium and maintained with enflurane and oxygen supplemented with pancuronium bromide in divided dose as needed. plasma concentrations of thyroxine and triiodothyronine were measured by means of radiommunoassay. The results obtained were as follows 1) No significant change in the plasma concentration of thyroxine was detected during enflurane anesthesia and surgery. 2) Plasma concentration of triidothyronine decreased significantly, compared with the control level, during enflurane anesthesia alone and anesthesia plus surgery. Although the precise mechanisms for the decrease in triiodothyronine following anesthesia and surgery remain unknown, decreased peripheral conversion from T4 to T3 may be responsible for this decline. Our data imply that enflurane anesthesia did not stimulate thyroid funcion judged by plasma concentration of T4 or T3. Therefore, enflurane anesthesia may be an useful anesthetics for patients with hyperthyroidism.