• Chest · Mar 2014

    Amiodarone induced thyrotoxicosis: should surgery always be delayed?

    • Nuno Ferreira and Alejandro Arbelaez.
    • Chest. 2014 Mar 1;145(3 Suppl):27A.

    Session TitleSurgery Case Report Posters ISESSION TYPE: Case Report PosterPRESENTED ON: Sunday, March 23, 2014 at 01:15 PM - 02:15 PMINTRODUCTION: Amiodarone induced thyrotoxicosis (AIT) is a serious complication of amiodarone treatment. After failure of medical treatment, total thyroidectomy allows to stop hyperthyroidism and restart the antiarrhythmic.Case PresentationA 52 years old man with obstructive hypertrophic cardiomyopathy (OHCM), echocardiography with severe left ventricular hypertrophy, preserved systolic function, SAM phenomenon and dynamic subaortic gradient, who started amiodarone after six episodes of rapid atrial fibrillation and four electrical cardioversion (EC). Two weeks later presented chest tightness, dyspnea, insomnia, warmth and loss of 2 kg. Thyroid profile shows TSH<0.008 ng/dL, T4 7.22 ng/dL, T3 406 ng/dL with no history of thyroid disease. Amiodarone was stopped, initiating antithyroid drug, propranolol and dexamethasone. After poor response (fT4 11.41 ng/dL, T3 262.40 ng/dL) plasmapheresis was made and due to the non-improvement (fT4 9.36 ng/dL, T3 297.46ng/dL) a total thyroidectomy with general anesthesia was decided. Esmolol was required as premedication with midazolam. Anesthesia induction with remifentanil, etomidate, rocuronium and maintained with sevoflurane was performed. An intraoperative EC and two more in early postoperative period was given. At 8th day post-thyroidectomy presented a new episode of atrial fibrillation requiring amiodarone impregnation. T4 was progressive decreased and levothyroxine was started.DiscussionAmiodarone may be the only effective antiarrhythmic. Its suspension can be followed by a rebound increase of triiodothyronine that can take months to resolve. AIT treatment includes antithyroid drugs, corticosteroids, betablockers at high doses and plasmapheresis that may temporarily improve the clinical situation. Thyroidectomy is most commonly performed under general anesthesia technique. Adequate premedication with esmolol to control heart rate and benzodiazepines for proper anxiolysis is recomended. Etomidate was used for its almost nonexistent cardiovascular effects. Neuromuscular blocking agents should be used with caution in hyperthyroidism by association with myopathy. During anesthesia maintenance, assumes particular importance the early detection of thyroid storm as well as hemodynamic changes associated to the OHCM. The aim is to preserve systolic volume, reduce contractility and sympathetic discharge, increase afterload, reducing oxygen demand and ensure a correct systemic vascular resistance. Intraoperative transesophageal echocardiography allows to detect early any mechanical dysfunction.ConclusionsThyroidectomy is ideally performed when the patient is euthyroid however manifestations of thyrotoxicosis and its influence on cardiac function may precede surgery. Surgery seems to be an effective and safe option when hyperthyroidism unresponsive to medical treatment and amiodarone is required.Reference #1: Tomisti L, et al. J. Clin. Endocrinol. Metab. 2012;97(10):3515-21.Reference #2: Poliac LC,et al. Anesthesiology. 2006;104(1):183-92.DisclosureThe following authors have nothing to disclose: Nuno Ferreira, Alejandro Arbelaez, Anna Gonzalez, Marius RocaNo Product/Research Disclosure Information.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…