Successful Pretreatment Using Plasma Exchange before Thyroidectomy in a Patient with Amiodarone-Induced Thyrotoxicosis

Abstract

Introduction: Amiodarone, used for the management of tachyarrhythmias, is associated with both hypothyroidism and thyrotoxicosis. Total thyroidectomy is an effective procedure for promptly reducing circulating thyroid hormone levels. It has been proposed in patients who have severe amiodarone-induced thyrotoxicosis (AIT) or are refractory to medical therapy, or when such therapy is contraindicated. Therapeutic plasma exchange (TPE) may be considered as a pretreatment for restoring a euthyroid state preoperatively, thereby reducing a patient's symptoms and the potential perioperative risk associated with thyrotoxicosis. Case Report: We describe the case of a 62-year-old man with type 2 AIT who presented with severe unremitting thyrotoxicosis after 8 weeks of medical therapy with glucocorticosteroids, thiamazole, and potassium perchlorate. Given the severity of his presentation, a total thyroidectomy was indicated. TPE was performed preoperatively and was successful in rapidly restoring euthyroidism. This dramatically improved the patient's symptoms which had been suggestive of ischemic heart disease. Subsequently, the patient underwent total thyroidectomy under general anesthesia without any major complications. Conclusion: TPE is successful in rapidly restoring a clinical and biochemical euthyroid state, and may be used to decrease the perioperative risks associated with thyroidectomy in patients with life-threatening thyrotoxicosis or in cases refractory to medical treatment.

Weathering the storm: A case of thyroid storm refractory to conventional treatment benefiting from therapeutic plasma exchange

“…The stimulating effect of amiodarone on the thyroid is often protracted due to its long half‐life. Moreover, these effects are characteristically resistant to conventional therapy with case reports demonstrating favorable patient outcomes with the use of TPE in this context . These cases suggest that the benefit of TPE may be due to a reduction in plasma concentrations of amiodarone.…”

“…There are several possible explanations for our patient's clinical improvement following TPE. First, drug‐associated thyrotoxicosis is a known side effect of amiodarone therapy . The stimulating effect of amiodarone on the thyroid is often protracted due to its long half‐life.…”

“…First, drugassociated thyrotoxicosis is a known side effect of amiodarone therapy. 12,13,19 The stimulating effect of amiodarone on the thyroid is often protracted due to its long half-life. Moreover, these effects are characteristically resistant to conventional therapy with case reports demonstrating favorable patient outcomes with the use of TPE in this context.…”

“…Moreover, these effects are characteristically resistant to conventional therapy with case reports demonstrating favorable patient outcomes with the use of TPE in this context. 12,13 These cases suggest that the benefit of TPE may be due to a reduction in plasma concentrations of amiodarone. However, despite being highly bound to plasma proteins (>98%), amiodarone has a large volume of distribution (5000 L) and demonstrates extensive equilibration from peripheral tissues, rendering TPE ineffective at removing this medication.…”

“…Evidence supporting the use of therapeutic plasma exchange (TPE) in the management of TS has appeared in a number of case reports and case series over the last 48 years. [5][6][7][8][9][10][11][12][13][14][15] However, the limited incidence of TS makes the performance of prospective randomized control trials difficult; thus, limited high-quality evidence exists to support the use of TPE in TS. Consequently, the American Society of Apheresis classifies the use of TPE for TS as a Category III recommendation, meaning that the role of apheresis in this clinical context has not been established.…”