You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Myxedema coma and explain in detail?
Myxedema coma is an extreme or decompensated form of hypothyroidism and while uncommon, is potentially lethal. A person may have laboratory values identical to a "normal" hypothyroid state, but a stressful event (such as an infection, myocardial infarction, or stroke) precipitates the myxedema coma state, usually in the elderly. Primary symptoms of myxedema coma are altered mental status and low body temperature. Low blood sugar, low blood pressure, hyponatremia, hypercapnia, hypoxia, slowed heart rate, and hypoventilation may also occur. Myxedema, although included in the name, is not necessarily seen in myxedema coma. Coma is also not necessarily seen in myxedema coma.According to newer theories, myxedema coma could result from allostatic overload in a situation where the effects of hypothyroidism are amplified by nonthyroidal illness syndrome.

Causes
Myxedema coma represents an extreme or decompensated form of hypothyroidism. Most cases occur in patients who have been previously diagnosed with hypothyroidism, yet in some cases, hypothyroidism may not have been previously identified. Common precipitating factors of myxedema coma include:

Hypothermia, especially during winter months
Metabolic disruption including hypoglycemia, hyponatremia, acidosis, and hypercalcemia
Respiratory compromise including hypoxemia and hypercapnia
Infections including pneumonia, cellulitis, and urosepsis
Congestive heart failure
Cerebrovascular accidents
Gastrointestinal bleeding
Trauma, motor vehicle accidents, and fractures
Medications including anesthetics, sedatives, tranquilizers, narcotics, amiodarone, and lithium
Withdrawal of thyroid supplements, especially in relation to a hospitalizationOther precipitating factors include:

Other medications including beta-blockers, diuretics, phenothiazines, phenytoin, rifampin, anti-TNF therapy
Burns
Influenza
Surgery
Consumption of raw bok choy
Diabetic ketoacidosis after total thyroidectomy

Pathophysiology
The thyroid gland is responsible for regulating whole-body metabolism through the production of two major hormones: thyroxine (T4) and triiodothyronine (T3). Of the metabolically active thyroid hormones, 93% is T4 and 7% is T3