Preoperative Lugol's Solution in Graves' Disease and Toxic Nodular Goiter

The purpose of this study is to assess if preoperative treatment with Lugol's solution prior to thyroidectomy can reduce the surgical complications hypoparathyroidism and laryngeal nerve palsy

Current practice in Sweden before thyroidectomy due to hyperthyroidism is preoperative treatment with antithyroid drugs (ATD) to all patients with Graves' disease and in cases of toxic nodular goiter with pronounced hyperthyroidism. Iodine solution is administered preoperatively in selected cases of Graves' disease where ATD is intolerable. In the cases where iodine is used it is in the form of extemporaneous prepared iodine potassium iodide solution (Lugol 5%). The dose varies in clinical studies. In American and Swedish guidelines the dose is 5-10 drops 3 times per day for 10 days prior to surgery. American guidelines recommend iodine as preoperative treatment i Graves' disease but this is based on sparse evidence. Iodine as preoperative treatment in toxic nodular goiter has yet not been studied. The purpose of this study is to assess if preoperative treatment with Lugol's solution prior to thyroidectomy due to hyperthyroidism reduce the surgical complications hypoparathyroidism and laryngeal nerve palsy. Before including toxic nodular goiters accepted for surgery, a pilot study will be performed on 20 patients with toxic nodular goiter. They will receive Lugol solution 3 times per day for ten days and thyroid hormone levels will be measured day 0, day 3-4, day 6-7 and after 10 days of Lugol treatment. Heart rate assessed and ThyPRO39 filled out before and after treatment.

Participants receive Iodine Potassium Iodide solution oral drops 3 times per day for 10 Days prior to thyroidectomy in addition to standard preoperative treatment

Numbers of participants with signs of hypoparathyroidism measured as hypocalcemia, low parathormone (PTH), supplementation with per oral vitamin D or calcium.

Number of patients with postoperative signs of vocal chord damage via clinical assessment or laryngoscopy.

Number of patients with postoperative signs of vocal chord damage via clinical assessment or laryngoscopy.

Numbers of participants with signs of hypoparathyroidism measured as hypocalcemia, low PTH, supplementation with per oral vitamin D or calcium.

Change from Baseline in Quality of Life on the Thyroid Specific Patient Reported Outcome 39 (ThyPRO 29) questionnaire

ThyPRO 39 is a validated thyroid specific Quality of Life form. Self reported questionnaire filled out before and after surgery. ThyPRO consists of 39 items grouped in 11 scales. Each item is is rated from 0 to 5 on a 5 point Likert scale. Increasing scores indicating decreasing quality of life. Lower scores indicating better quality of life.

Inclusion Criteria: Hyperthyroidism accepted for thyroidectomy due to toxic nodular goiter with free T4 <30 pmol/L or Graves' disease Signed informed consent Exclusion Criteria: Unstable coronary artery disease Previous thyroid surgery Congestive heart failure Renal insufficiency Hepatic failure Current infection Treatment with steroids or anticoagulants Thyroid associated orbitopathy CAS > 2 Diabetes mellitus type 1 Active cancer Severe psychiatric illness Amiodarone treatment Pregnancy Breast feeding Women of child bearing potential not using contraceptive Inability to comprehend the meaning of the study Iodine hypersensitivity

The original contributions presented in the study are included in the article/supplementary material.

The original contributions presented in the study are included in the article/supplementary material. Inquiries can be directed to the corresponding author after publication.

Ross DS, Burch HB, Cooper DS, Greenlee MC, Laurberg P, Maia AL, Rivkees SA, Samuels M, Sosa JA, Stan MN, Walter MA. 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis. Thyroid. 2016 Oct;26(10):1343-1421. doi: 10.1089/thy.2016.0229. Erratum In: Thyroid. 2017 Nov;27(11):1462.

Kaur S, Parr JH, Ramsay ID, Hennebry TM, Jarvis KJ, Lester E. Effect of preoperative iodine in patients with Graves' disease controlled with antithyroid drugs and thyroxine. Ann R Coll Surg Engl. 1988 May;70(3):123-7.

Randle RW, Bates MF, Long KL, Pitt SC, Schneider DF, Sippel RS. Impact of potassium iodide on thyroidectomy for Graves' disease: Implications for safety and operative difficulty. Surgery. 2018 Jan;163(1):68-72. doi: 10.1016/j.surg.2017.03.030. Epub 2017 Nov 3.

Whalen G, Sullivan M, Maranda L, Quinlan R, Larkin A. Randomized trial of a short course of preoperative potassium iodide in patients undergoing thyroidectomy for Graves' disease. Am J Surg. 2017 Apr;213(4):805-809. doi: 10.1016/j.amjsurg.2016.07.015. Epub 2016 Aug 4.

Marigold JH, Morgan AK, Earle DJ, Young AE, Croft DN. Lugol's iodine: its effect on thyroid blood flow in patients with thyrotoxicosis. Br J Surg. 1985 Jan;72(1):45-7. doi: 10.1002/bjs.1800720118.

Yilmaz Y, Kamer KE, Ureyen O, Sari E, Acar T, Karahalli O. The effect of preoperative Lugol's iodine on intraoperative bleeding in patients with hyperthyroidism. Ann Med Surg (Lond). 2016 Jun 16;9:53-7. doi: 10.1016/j.amsu.2016.06.002. eCollection 2016 Aug.

Huang SM, Liao WT, Lin CF, Sun HS, Chow NH. Effectiveness and Mechanism of Preoperative Lugol Solution for Reducing Thyroid Blood Flow in Patients with Euthyroid Graves' Disease. World J Surg. 2016 Mar;40(3):505-9. doi: 10.1007/s00268-015-3298-8.

Calissendorff J, Falhammar H. Rescue pre-operative treatment with Lugol's solution in uncontrolled Graves' disease. Endocr Connect. 2017 May;6(4):200-205. doi: 10.1530/EC-17-0025. Epub 2017 Mar 21.

Calissendorff J, Falhammar H. Lugol's solution and other iodide preparations: perspectives and research directions in Graves' disease. Endocrine. 2017 Dec;58(3):467-473. doi: 10.1007/s12020-017-1461-8. Epub 2017 Oct 26.

Spallek L, Krille L, Reiners C, Schneider R, Yamashita S, Zeeb H. Adverse effects of iodine thyroid blocking: a systematic review. Radiat Prot Dosimetry. 2012 Jul;150(3):267-77. doi: 10.1093/rpd/ncr400. Epub 2011 Oct 20.

Nauman J, Wolff J. Iodide prophylaxis in Poland after the Chernobyl reactor accident: benefits and risks. Am J Med. 1993 May;94(5):524-532. doi: 10.1016/0002-9343(93)90089-8. No abstract available.