Changes in Thyroid Function in Patients Undergoing Cardiac Surgery Using Cardiopulmonary Bypass

Abstract

INTRODUCTION: After open heart surgery (OHS) using cardiopulmonary bypass (CPB), abnormalities in the circulating thyroid hormone levels are found in the absence of primary thyroid disease; this is collectively called the sick euthyroid syndrome (SES). AIMS ANDOBJECTIVES: To study thyroid function test in patients planned for cardiac surgery under cardiopulmonary bypass. MATERIALS AND METHODS: This study included a total of 150 patients, of any age, either sex, planned for cardiac surgery under cardiopulmonary bypass (like Valve replacement, CABG, myxoma excision, congenital Heart Diseases like ASD, VSD, TOF). To assess the levels of thyroid hormone, TSH, TT3 and TT4 were measured. The blood samples were collected at regular intervals: preoperatively, on 2nd postoperative day and on 7th postoperative day. CONCLUSION: In our study the levels of thyroid hormone (TT4 and TT3) decreased significantly after cardiopulmonary bypass. Keywords: Open Heart Surgery (OHS), Cardiopulmonary Bypass (CPB), Sick Euthyroid Syndrome (SES)