Dionigi, Gianlorenzo1; Lavazza, Matteo1; Rausei, Stefano1; Rovera, Francesca1; Inversini, Davide1
1 1st Division of General Surgery, Research Center for Endocrine Surgery, Department of Surgical Sciences and Human Morphology, University of Insubria (Varese-Como)
Background: Neuromonitoring (NM) in thyroid surgery improves the intraoperative assessment of RLN function. We describe our patient management after loss of EMG signal at the end of the first lobectomy.
Material and methods: Standard NM technique was applied with both vagal and RLN stimulation (V1,R1,R2,V2). Patients underwent pre-and postoperative laryngoscopy. Patient were informed of the possibility of stage thyroidectomy preoperatively.
Results: In 23 patients over 803 consecutive thyroid procedure (2,8%), V2 signal after first lobe exeresis was missing (loss of signal LOS <150mcV). In 20/23 of cases we stopped the surgical procedure (stage-thyroidectomy). In the 3 cases with malignancy and severe co-morbidities (ASA3-4score) total thyroidectomy was performed at once. In this cases, such strategy was discussed preoperatively with patients, in none of these cases bilateral RLN occurred (only monolateral transient). Postoperative laringoscopy confirmed RLN palsy in 21/23 cases. All true positive patients were supported by speech therapy. False positive (N.2), malignant (N.8) and symptomatic goiters (N.7) underwent completion thyroidectomy within 6 months. One case underwent RAI for hyperthyroidism. Two patients underwent only follow-up.
Discussion & Conclusion: NM changes surgical decision-making process in a multidisciplinary manner. A reduced EMG signal at the first side, may induce the surgeon not to complete total thyroidectomy thus avoiding a risk of bilateral RLN injury. We stress the importance of a dedicated informed consent with emphasis on shared decision making with patient, anesthesiologist and endocrinologist.