Effectiveness and Mechanism of Preoperative Lugol Solution for Reducing Thyroid Blood Flow in Patients with Euthyroid Graves' Disease

Background: To reduce intraoperative and postoperative complications, using Lugol solution to preoperatively prepare patients with Graves' disease has (1) rapidly reduced the severity of thyrotoxicosis and (2) reduced the vascularity of the thyroid gland. The vascularity reduction normally accompanies reducing the severity of thyrotoxicosis. However, the effects and mechanism of Lugol solution for reducing blood flow have not been well investigated in the patients with euthyroid (normally functioning thyroid) Graves' disease. Methods: Twenty-five patients with euthyroid Graves' disease being preoperatively treated with Lugol solution for 10 days were measured, at baseline and on the operative day, for (1) superior thyroid artery blood flow; (2) systemic angiogenic factor (VEGF); and (3) systemic inflammatory factor [interleukin (IL)-16]. Results: All three parameters were significantly (p < 0.0001) lower after 10 days of Lugol solution treatment. The average reductions were blood flow: 60 % (0.294 vs. 0.117 L/min), serum VEGF: 55 % (169.8 vs. 76.7 pg/mL), and serum IL-16: 50 % (427.2 vs. 214.2; pg/mL). Conclusion: Lugol solution significantly reduced thyroid arterial blood flow, VEGF, and IL-16, even in patients with euthyroid Graves' disease. We recommend routine preoperative Lugol solution treatment for all patients with Graves' disease.