Myxedema Coma in the ED

Myxedema coma is decompensated severe hypothyroidism marked by altered mental status, hypothermia, and bradycardia. In the ED, the diagnosis is often missed because early symptoms are nonspecific, while treatment hinges on supportive care, thyroid hormone replacement, and finding the precipitating trigger.

Recognizing Myxedema Coma

• Classic triad recognition: Altered mental status, hypothermia, and bradycardia are the bedside trio that should immediately raise concern for myxedema coma, especially in an older patient with known hypothyroidism.
• Early symptom pattern: Fatigue, activity intolerance, and persistent cold intolerance often precede collapse, making a careful symptom timeline and medication history more useful than the initial complaint suggests.
• High-risk patient profile: Untreated hypothyroidism, recent medication interruption, and elderly patients dependent on others for pill administration are recurring setup factors for this presentation.
• Precipitating stressors: Infection, trauma, surgery, cold exposure, and sedatives or narcotics can tip compensated hypothyroidism into myxedema coma. We get into the common ED trigger patterns in the episode.

ED Workup and Initial Management

• Core diagnostic studies: TSH, free T4, cortisol, electrolytes, glucose, CBC, CMP, ABG, and infection screening frame both the diagnosis and the metabolic complications that often drive instability.
• Electrocardiographic clues: Bradycardia, low voltage, and QT prolongation are the ECG findings that fit severe hypothyroidism and help explain hemodynamic fragility in the sickest patients.
• Supportive care priorities: Initial management starts with ABCs, cautious fluids for hypotension, and gentle rewarming, because aggressive volume loading or rapid warming can worsen an already unstable physiology.
• Hormone and steroid therapy: IV levothyroxine is the cornerstone of definitive treatment, and hydrocortisone is commonly paired early while adrenal insufficiency is still in the differential.
• Escalation decisions: Refractory hypotension may require vasopressors, severe bradycardia can push pacing discussions, and some patients need ICU transfer for replacement and monitoring nuances we cover in the chapter.

References:

1. Han KW, Lin CC, Chen CY, Chao HY, Chien CY, Chen HY. Myxedema Coma Patient in Emergency Department: A Case Report. J Acute Med. 2017;7(4):171-173.  PMID: 32995192
2. https://www.ebmedicine.net/topics/endocrine/thyroid-storm-myxedema-coma