What is the treatment for myxedema coma, a severe form of hypothyroidism?

From the Guidelines

Myxedema coma is a life-threatening emergency requiring immediate treatment in an intensive care unit, with management including thyroid hormone replacement and supportive care as outlined in the most recent guidelines. According to the 2021 ASCO guideline update 1, myxedema coma is a severe and life-threatening condition that requires hospital admission and a high level of care. The management of myxedema coma involves thyroid hormone replacement, with intravenous levothyroxine (T4) dosing and supportive care, including steroids, as mentioned in the guideline for grade 3-4 hypothyroidism 1.

Some key points to consider in the management of myxedema coma include:

• Thyroid hormone replacement with intravenous levothyroxine (T4)
• Concurrent administration of intravenous hydrocortisone until adrenal insufficiency is ruled out, as suggested in the guideline for uncertainty about primary or central hypothyroidism 1
• Supportive care, such as mechanical ventilation, careful fluid management, passive warming, and treatment of precipitating factors
• Close monitoring of vital signs, mental status, and electrolytes

It is essential to note that myxedema coma results from severe, longstanding hypothyroidism, and despite optimal treatment, mortality remains high, emphasizing the importance of early recognition and aggressive management 1. The guideline recommends holding ICPi until symptoms resolve to baseline with appropriate supplementation and endocrine consultation to assist with rapid hormone replacement for severe symptoms 1.

From the FDA Drug Label

Myxedema Coma Myxedema coma is usually precipitated in the hypothyroid patient of long standing by intercurrent illness or drugs such as sedatives and anesthetics and should be considered a medical emergency. An intravenous preparation of liothyronine sodium is marketed under the trade name Triostat® for use in myxedema coma/precoma

The treatment for myxedema coma involves the administration of intravenous liothyronine sodium, which is marketed under the trade name Triostat. This condition is considered a medical emergency and requires prompt treatment.

• Key points:
  • Myxedema coma is usually precipitated by intercurrent illness or certain drugs.
  • It should be considered a medical emergency.
  • Intravenous liothyronine sodium (Triostat) is used for treatment. 2

From the Research

Definition and Characteristics of Myxedema Coma

• Myxedema coma is a rare endocrine emergency resulting from the decompensation of severe hypothyroidism, associated with a high mortality rate 3.
• It is characterized by deterioration of mental status, hypothermia, hypotension, hyponatremia, and hypoventilation 3, 4.
• Patients with hypothyroidism may exhibit physiologic alterations to compensate for the lack of thyroid hormone, but if these homeostatic mechanisms are overwhelmed, the patient may decompensate into myxedema coma 4.

Diagnosis of Myxedema Coma

• The diagnosis of myxedema coma is based on clinical suspicion, especially in patients with hypothyroidism and in the presence of precipitating factors 5, 4.
• Diagnostic and scoring criteria based on clinical, laboratory, and imaging features have been proposed, but no consensus has been reached 5.
• Physicians should include hypothyroidism in the differential diagnosis of every patient with hyponatremia 4.

Treatment of Myxedema Coma

• Early disease diagnosis and advancements in intensive supportive care have reduced the mortality rate 3.
• Appropriate management of the underlying thyroid hormone deficiency is essential, and treatment with intravenous levothyroxine (T4) is often recommended 4.
• However, oral levothyroxine can be an effective option in resource-limited settings where intravenous thyroid hormone replacement is not available 5, 6.
• Hydrocortisone should be administered until coexisting adrenal insufficiency is ruled out 4.
• A combination therapy of levothyroxine and liothyronine can also be effective in treating myxedema coma 3.

Complications and Challenges

• Myxedema coma can result in profound hemodynamic instability and airway compromise 7.
• Unanticipated posterior pharyngeal edema in myxedema coma can severely complicate airway management 7.
• Emergency physicians should anticipate a potentially difficult airway in all myxedema coma patients regardless of the degree of external facial edema present 7.