Randomized clinical trial, blinded for the researcher and multicenter, to evaluate the efficacy and safety of preoperative preparation with Lugol solution in euthyroid patients with Graves-Basedow disease.

INTERVENTION: Trade Name: Solución de Lugol Fuerte Pharmaceutical Form: Oral solution INN or Proposed INN: Solución Fuerte de Lugol CAS Number: 8500003‐09‐0 Current Sponsor code: Solución Fuerte de Lugol Other descriptive name: AQUEOUS IODINE SOLUTION Concentration unit: % percent Concentration type: equal Concentration number: 5‐ CONDITION: Graves‐Basedow disease ; MedDRA version: 20.0 Level: LLT Classification code 10065624 Term: Graves‐Basedow disease System Organ Class: 100000004860 Therapeutic area: Diseases [C] ‐ Hormonal diseases [C19] PRIMARY OUTCOME: ; Secondary Objective: ‐ To analyze whether, in patients undergoing TT, preoperative non‐preparation with LS influences intraoperative results.; ‐ To analyze whether, in patients undergoing TT, preoperative non‐preparation with LS influences the postoperative long of stay or the rate of readmissions, when compared with the group of patients who do receive such preparation.; ‐ To analyze if, in patients undergoing TT, preoperative non‐preparation with LS does not increase the appearance of permanent complications, including hypoparathyroidism or RLN injury, when compared with the group of patients who do they receive this preparation.; ‐ Determine the safety profile of the use of the LS.; ‐ Detect if there are subgroups of patients undergoing TT, in which the non‐preparation with LS is particularly beneficial or harmful.; ‐ Compare the results obtained according to the technical variations used by each unit.; Main Objective: To analyze whether, in euthyroid patients undergoing TT due to GD, preoperative non‐preparation with LS increases the appearance of postoperative complications compared to the use of LS preparation. Primary end point(s): The main variable will therefore be the appearance of at least one postoperative complication: hypoparathyroidism, RLN injury, postoperative hematoma, SSI or postoperative death. Timepoint(s) of evaluation of this end point: 6 months SECONDARY OUTCOME: ; Secondary end point(s): Preoperative variables; ‐ Demographic variables: birthdate, gender and ethnicity.; ‐ Drugs allergies. Allergy to iodine.; ‐ Personal history and usual treatment.; ‐ Aspects related to the GD: date of diagnosis, use of AT drugs and/or RI, existence of ophthalmopathy, existence of cervical compression symptoms and indication of surgery.; ‐ Physical exploration: body mass index, pulse at rest and blood pressure and cervical palpation.; ‐ Laboratory tests: hematocrit, leukocytes, neutrophils, platelets, INR, creatinine, potassium, total calcium, albumin, total proteins, PTH, 25‐OH‐vitamin D, free T4 and / or free T3, TSH, TSI.; ‐ Classification of the anesthetic risk of ASA.; ‐ Cervical ultrasound: existence of thyroid nodules and volume of the thyroid.; ‐ Mobility of the vocal cords evaluated by laryngoscopy.; ‐ Compliance with assigned treatment: the patient assigned to the LS arm must have consumed at least 80% of the total dose indicated.; ; Intraoperative variables; ‐ Surgical time.; ‐ Antibiotic prophylaxis.; ‐ Intraoperative hemorrhage.; ‐ Thyroidectomy Difficulty Scale.; ‐ Loss of electromyographic signal during neural intraoperative monitorization.; ‐ Accidental parathyroidectomy.; ‐ Section or obvious lesion of the NLR.; ‐ Trachea or esophagus perforation.; ‐ Weight of the gland.; ‐ Electrosurgical hemostasis system used during the intervention.; ‐ Maneuvers used to check hemostasis.; ‐ Hemostats used during the intervention.; ‐ Use of drainage.; ‐ Definitive surgical technique: TT, unilateral or bilateral subtotal thyroidectomy or hemithyroidectomy.; ; Postoperative variables; ‐ Early complications: hypoparathyroidism, RLN paralysis of the NLR, postoperative hematoma, SSI or death.; ‐ Debit for surgical drains.; ‐ Postoperative hospital long of stay.; ‐ Anatomopathological variables: histological diagnosis compatible with EG and existence of parathyroid glands in the surgical specimen.; ‐ Long‐term complications: hypocalcemia and/or permanent vocal cord paralysis longer than 6 months; Timepoint(s) of evaluation of this end point: 6 months INCLUSION CRITERIA: ‐ The age of the patient must be over 18 years of age. ‐ The patient or his / her tutor, in cases where this is the case, has the capacity to understand the study and agrees to participate in it, by signing the corresponding informed consent document. ‐ Patients who have been diagnosed with GD, defined as the existence of hyperthyroidism (TSH < lower limit of laboratory normality associated with TSI > upper limit of laboratory normality) that present ultrasonographic data (diffuse vascularization increase) and / or scintigraphy (diffuse uptake of the radioisotope) compatible with EG. ‐ Euthyroid patients (free T4 and / or free T3 within the normal range of the laboratory) at the time of randomization, and under treatment with AT drugs (propylthiouracil, carbimazole or methimazole). ‐ The patient must be proposed for total thyroidectomy, using a transcervical approach.