SUBMANDIBULAR SPACE AIRWAY OBSTRUCTION: A RARE PRESENTATION OF MYXEDEMA COMA

Abstract

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Myxedema coma is an uncommon manifestation of severe hypothyroidism. Classically, as symptoms of hypothyroidism progresses patients exhibit signs of myxedema including generalized edema, ptosis and hypoventilation. Rarely, myxedema coma can present with isolated mucin collections around the salivary glands and facial skin. This causes progressive facial swelling leading to airway obstruction, requiring emergent advanced airway management CASE PRESENTATION: A 37-year-old male presented to an outside hospital with worsening altered mental status, progressive submandibular swelling, stridor, and acute hypoxic respiratory failure. His past medical history included hypothyroidism and cerebral palsy. His vitals prior to transfer were unremarkable other than tachypnea and hypoxia with an O2 saturation of 85%. Labs at the outside hospital revealed a leukocytosis of 15K and euvolemic hyponatremia with a sodium of 127. Due to the patients worsening respiratory status he was emergently intubated. The patient was transferred to our ICU for a higher level of care. On arrival, the patient was hypothermic with a temperature of 94.7F, and in sinus bradycardia with a rate of 54. He was also hypotensive requiring norepinephrine. IV antibiotics were initiated. On examination, he had firm, fixed submandibular swelling with no palpable fluctuating mass. His exam was otherwise unremarkable. The patient underwent a CT scan of the head and neck with contrast which showed nonspecific soft tissue swelling without evidence of abscess or infection. Further Infectious disease workup was unremarkable. A TSH was ordered and found to be significantly elevated at 60 with an undetectable T4 level, consistent with myxedema coma. Endocrinology was consulted and the patient was promptly started on IV levothyroxine. Over the next several days his mental status improved with stabilization of his vital signs. His submandibular swelling improved and the patient was subsequently extubated. He was eventually discharged home. DISCUSSION: Facial swelling is a known manifestation of myxedema coma. These manifestations classically present as dry facial skin, periorbital facial, and tongue swelling. Rarely, myxedema coma can present with isolated submandibular facial swelling leading to progressive airway compromise requiring emergent intubation. Vitals signs expected with myxedema coma may not initially be present. Mortality in these patients is approximately 30%. Myxedema coma must be ruled out in patients with progressive airway compromise as it can be effectively treated, however to miss the diagnosis is lethal. CONCLUSIONS: Although infectious and hypersensitive conditions are common causes, myxedema coma should be on a clinician's differential diagnosis for progressive facial swelling. Evaluation for myxedema coma is standard of care in patients with progressive airway obstruction. REFERENCE #1: Wall, C., 2021. Myxedema Coma: Diagnosis and Treatment. [online] Aafp.org. Available at: <https://www.aafp.org/afp/2000/1201/p2485.html> [Accessed 6 April 2021]. REFERENCE #2: Susan S. Braithwaite, Critical Care Medicine (Third Edition), Mosby,2008, Pages 1281-1306, ISBN 9780323048415, https://doi.org/10.1016/B978-032304841-5.50063-7. (https://www.sciencedirect.com/science/article/pii/B9780323048415500637) REFERENCE #3: Leonard Wartofsky, Myxedema Coma?, Editor(s): Ilpo Huhtaniemi, Luciano Martini, Encyclopedia of Endocrine Diseases (Second Edition), Academic Press,2018, Pages 627-629, ISBN 9780128122006, https://doi.org/10.1016/B978-0-12-801238-3.04171-4. (https://www.sciencedirect.com/science/article/pii/B9780128012383041714) DISCLOSURES: No relevant relationships by Zachary Fyffe, source=Web Response No relevant relationships by Matthew Mitchell, source=Web Response