Thyroid hormone in cardiac surgery

Thyroid hormone has a wide range of cardiovascular effects which are mediated at both genomic and non-genomic levels. As a stress response to surgery, the non-thyroidal illness syndrome or euthyroid sick syndrome occurs in the post-operative period following cardiac surgery. There remains debate about the potential benefits of the treatment of the non-thyroidal illness syndrome in this setting with acute thyroid hormone supplementation. This review article sets out to discuss the potential benefits of thyroid hormone supplementation and the results from trials relating to both adult and paediatric cardiac surgical population as well as in the setting of brain stem death to optimise the potential cardiac donor.