Open AccessThe Influence of Various Anesthetics on the Release and Metabolism of Thyroid Hormones
Author(s) -
U. Börner,
Markus Klimek,
Helmut Schoengen,
John Lynch,
Claudia Peschau,
H. Schicha
Publication year - 1995
Publication title -
anesthesia and analgesia/anesthesia and analgesia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.404
H-Index - 201
eISSN - 1526-7598
pISSN - 0003-2999
DOI - 10.1097/00000539-199509000-00034
Subject(s) - medicine , hormone , thyroid , triiodothyronine , thyroid hormones , enflurane , endocrinology , plasma concentration , free thyroxine , anesthesia , halothane , thyroid function
Normal functioning of the thyroid gland during surgery is important, but few data are available on the possible interactions between anesthesia and thyroid hormones. In two independent studies we examined the influence of different types of general anesthesia on the plasma levels of the thyroid hormones. They revealed an intraoperative increase of free thyroxine (fT4) and total thyroxine (tT4) in plasma to approximately 150% of preanesthesia levels when enflurane was used. No increase in thyroid-stimulating hormone (TSH) secretion was noted prior to this. The increase was not due to a quantitative change in the binding proteins. The plasma levels of fT4 and tT4 returned to normal postoperatively; however, no accompanying increase in plasma triiodothyronine levels was observed. Hence we assume the increase to be due to hormone release from thyroid and/or extrathyroidal stores--an intercompartmental shifting.