Introduction Gradual enlargement of multinodular goiter (MNG) may compress surrounding structures which may progressively cause complications of tracheal stenosis and airway compromise. Surgical resection remains the gold standard treatment in MNG patients presenting with respiratory distress. In the current global COVID -19 pandemic, compressive goiter should be a differential diagnosis in patients with stable benign thyroid goiter presenting with dyspnea. We present a case of MNG with life threatening airway obstruction during an active COVID-19 infection. Case presentation A 74-year-old female with a history of hyperthyroidism with multi-nodular goiter and recurrent atrial fibrillation status-post ablation, was transferred to the intensive care unit for treatment after being intubated for respiratory distress at a nearby hospital. She was diagnosed with hyperthyroidism about 40 years ago and managed with methimazole. Over the last two years, thyroid ultrasound and prior imaging showed MNG with patent but moderate tracheal narrowing; fine-needle aspiration (FNA) confirmed benign colloid nodules with cystic degeneration. She was pending cardiac clearance for surgery when symptoms acutely worsened two days before admission. On initial assessment, she was hemodynamically stable, afebrile, with oxygen saturation of 86% on room air. She was alert and able to follow commands. On physical examination, she had stridor and thyromegaly was evident with mild tenderness on palpation. Cardiopulmonary examination was remarkable for coarse breath sounds. Labs showed TSH 4.82 (Normal 0.3 - 4.5 ulU/mL), FT4 0.64 (Normal 0.5- 1.26 ng/dL). Respiratory panel test came back positive for SARS-CoV-2. Racemic epinephrine and albuterol nebulizers were administered to help with her symptoms. CT scan of the neck revealed a severe narrowing and mild rightward shift of the trachea by a large multinodular goiter, prompting the decision to intubate for airway protection. CT scan of the chest with contrast demonstrated the large MNG with tracheal stenosis. Her methimazole dose was adjusted. After cardiac clearance, she underwent thyroidectomy through a transcervical approach. Levothyroxine and calcium supplementation were started post-surgery. She was extubated two days after her thyroidectomy. Pathology results showed no evidence of malignancy. Discussion Acute airway obstruction by large MNG requiring emergent airway protection is rare. Typically airway compromise from large otherwise stable benign goiters results from sudden hemorrhage into a cyst, upper respiratory tract infection leading to tracheal edema, or worseningcomorbid conditions. During the COVID-19 pandemic, acute respiratory failure and shortness of breath is typical of worsening disease course. This case highlights the importance of maintaining wider differentials of respiratory failure even and we need to consider worsening of tracheal narrowing with a large goiter due to tracheal edema from SARS- CoV-2 Infection. Thyroidectomy before SARS-CoV-2 infection may have reduced her need for emergent intubation for acute respiratory failure by improving pre existing airway compression. Presentation: No date and time listed
Introduction Management of amiodarone induced thyrotoxicosis (AIT) presents the clinical challenge of differentiating between the two subtypes: Type I AIT, characterized by increased hormonal biosynthesis, and Type II AIT, a destructive thyroiditis since the treatment differs. We present a case of a patient with severe cardiac disease on long-term amiodarone who presented with thyrotoxicosis who was minimally clinically symptomatic despite significant biochemical thyroid function abnormalities and refractory to all medical interventions, including plasmapheresis, ultimately requiring total thyroidectomy. Case Description An 82 year-old-male with severe cardiac disease including coronary artery disease with prior CABG, EF of 25-30% with ICD, and atrial fibrillation on amiodarone, presented to the hospital due to palpitations and multiple shocks delivered by patient's ICD. EKG revealed atrial fibrillation and the ICD demonstrated episodes of sustained ventricular tachycardia. The Burch-Wartofsky score was 25. He had palpitations, tremors, and atrial fibrillation but no thyromegaly, thyroid bruits or thyroid eye disease. Thyroid function testing was TSH <0. 01 ulU/mL (Normal 0.3 - 4.5 ulU/mL), FT4 5.29 ng/dL (Normal 0.5- 1.26 ng/dL). Thyroid ultrasound showed multiple sub-centimeter nodules without increased vascularity. Since patient had characteristics of both AIT subtypes, patient was started on treatments for both including hydrocortisone 100 mg TID, Lugol's Iodine 10 drops TID, methimazole 20 mg QID, propranolol 20 mg QID, cholestyramine 4g BID, and lithium 300 mg TID. Despite extensive medical management, the patient's thyroid levels remained grossly elevated with FT4 nadir of 4.37 ng/dL. Plasmapheresis was initiated every 1-2 days for a total of 6 treatments and the patient's FT4 improved to 3.52 ng/dL before increasing again. During this treatment period, the patient remained relatively asymptomatic but had severe cardiac disease which further complicated the urgency for thyroidectomy. Ultimately, he underwent a total thyroidectomy that caused the resolution of the thyrotoxicosis. He was started on levothyroxine and subsequent pathology revealed multi-nodular goiter with lymphocytic thyroiditis. Discussion This challenging case of amiodarone induced thyrotoxicosis in a patient with severe cardiac disease, refractory to extensive medical therapy including plasmapheresis and requiring total thyroidectomy, highlights the difficulty in management of AIT. Management of refractory AIT involves differentiating between the two clinical subtypes with the goal of expediently achieving a euthyroid state to avoid severe cardiac complications and mortality. This case was particularly challenging since our patient had relatively stable clinical status despite chemical thyrotoxicosis with characteristics of both subtypes of AIT. It was challenging to optimize a patient's thyroid levels prior to thyroidectomy, due to severe cardiac disease and persistent thyrotoxicosis. Ultimately, our patient was refractory to medical treatments for both AIT subtypes and plasmapheresis. The resolution of thyrotoxicosis was not achieved until he underwent total thyroidectomy Presentation: No date and time listed
59-year-old female with PMH of Bipolar disorder and Pituitary macroadenoma presented to the ER yesterday for worsening Headache associated with nausea, vomiting and double vision. Detailed imaging of the pituitary gland demonstrated a hypo enhancing sellar and suprasellar mass extending asymmetric to the right, appears to fill and expand the right cavernous sinus. This was associated with T2 hypo intensity. The hypo enhancing mass measured around 2.9 cm AP by 2.7 cm transverse by 3.5 cm CC, previously 2.9×2.4×3.1 cm. Of note, she was found to have this pituitary macroadenoma non-functional on prior testing. Important to note that she had history of bipolar disorder and it was refractory to many medications and was started on Lithium 10 months prior to this presentation. She underwent Image Guided Endoscopic Trans nasal Transsphenoidal Resection of Pituitary Tumor with reconstruction with Nasoseptal Flap, Lumbar Drain Placement, and Injection of Intrathecal Fluorescein Dye. Her postoperative course was complicated by Central DI and was started on DDAVP treatment. Eventually she developed Panhypopituitarism and needed Levothyroxine and Hydrocortisone replacement therapy. She had a prolonged hospital course due to post-surgical meningitis resulting in fever and encephalopathy. She had persistent hypernatremia and lithium was discontinued given the fact she was found to be in Nephrogenic DI and her hypernatremia requiring intravenous D5 water fluid treatment for a brief period. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.
The ability of a material to display two equilibrium states, called bistability, has been previously observed in carbon fiber reinforced polymers (CFRPs). For bistability to occur, the laminate must consist of an unsymmetric layup about its midplane which generates internal residual stress from thermal contraction. Prior studies have observed bistability in CFRPs with small-scale rectangular geometries where all sides were less than 250 mm. The aim of this paper is to demonstrate the existence of bistability in large-scale CFRPs with rectangular and non-rectangular geometries. Experiments and finite element analyses were conducted to determine the viability of bistability in large-scale CFRPs where at least one length aspect of the specimen was greater than or equal to 304.8 mm. Specimens whose shapes included rectangles, deltoids, triangles, and circles, were fabricated and tested to determine the presence of bistability and the associated curvature for each cured equilibrium state. Rectangular specimens had a side length of 914.4 mm and widths that varied from 177.8 to 457.2 mm. For the deltoids, triangles, and circles, one length aspect (i.e. the height, hypotenuse, and diameter, respectively) equaled 304.8 mm. Finite element models were created to compare the equilibrium shapes’ curvatures and displacements with the experimental laminates; the existence of bistability was also examined using a nondimensionalized bifurcation plot. Experimentally, bistability was found to occur for the fabricated laminates up to six plies. As the studied laminates could be considered thin, they displayed cylindrical cured shapes. The non-traditional shaped CFRPs followed bistability trends found for traditional, small-scale, rectangular laminates. An inverse relationship between the ply count and curvature was exhibited for the large-scale, rectangular laminates; curvature decreased as the number of plies in the laminate increased.
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