Myxedema coma

Myxedema coma is seen in advanced hypothyroidism. These patients develop CNS depression, respiratory depression, cardiovascular instability, and fluid and electrolyte disturbances. Myxedema coma often is triggered by an underlying acute medical condition such as infection, stroke, trauma, or administration of CNS depressant drugs. 

The treatment of myxedema coma can include which of the following agents ... 

The following factors have been suggested as alternatives to consider when presented with a potential case of exposure to carbon monoxide diabetic ketoacidosis, hypothyroidism and myxedema coma, labyrinthitis, and lactic acidosis toxic exposures resulting in methemoglobinemia ingestion of alcohols or narcotics and diseases that cause gastroenteritis, encephalitis, meningitis, and acute respiratory distress syndrome. 

Myxedema coma is a rare consequence of decompensated hypothyroidism manifested by hypothermia, advanced stages of hypothyroid symptoms, and altered sensorium ranging from delirium to coma. Untreated disease is associated with a high mortality rate. 

Myxedema coma/precoma (injection oniy) For the treatment of myxedema coma/precoma. 

Myxedema coma - Oral thyroid hormone drug products are not recommended to treat this condition administer thyroid hormone products formulated for IV. 

In myxedema coma or stupor, without concomitant severe heart disease, 200 to 500 meg of levothyroxine for injection may be administered IV as a solution containing 100 mcg/mL. Do not add to other IV fluids. Although the patient may show evidence of increased responsivity within 6 to 8 hours, full therapeutic effect may not be evident until the following day. An additional 100 to 300 meg or more may be given on the second day if evidence of significant and progressive improvements has not occurred. Maintain continued daily administration of lesser amounts parenterally until the patient is fully capable of accepting a daily oral dose. 

Myxedema coma/precoma (injection only) - For IV use only do not give IM or subcutaneously. Give doses at least 4 hours, and not more than 12 hours, apart. Giving at least 65 mcg/day initially is associated with lower mortality. 

Myxedema Start dosage at a very low level and increase gradually. Myxedema coma therapy requires simultaneous administration of glucocorticoids. 

Parenterally it is indicated in the management of myxedema coma or when thyroxine cannot be given orally. Onset of action occurs within a few hours and its activity lasts for some days after withdrawal of therapy. 

The most extreme manifestation of untreated hypothyroidism is myxedema coma, which even if detected early and appropriately treated, carries a mortality rate of 30 to 60%. Myxedema coma is a misnomer. Most patients exhibit neither the myxedema nor coma. Patients with myxedema coma usually have longstanding hypothyroidism with the classic symptoms of hypothyroidism. Decompensation into myxedema coma may occur when the homeostatic mechanisms of the severely hypothyroid patient are subject to a stressful precipitating event (e.g., infection, trauma, some medications, stroke, surgery). The principal manifestation of myxedema coma is a deterioration of mental status (apathy, confusion, psychosis, but rarely coma). Other common clinical features include hypothermia, diastolic hypertension (early), hypotension (late), hypoventilation, hypoglycemia, and hyponatremia. If myxedema coma is suspected, the patient is usually admitted to an intensive care unit for pulmonary and cardiovascular support... 

Liothyronine sodium (Cytomel) is the sodium salt of the naturally occurring levorotatory isomer of T3. Liothyronine is generally not used for maintenance thyroid hormone replacement therapy because of its short plasma half-life and duration of action. The use of T3 alone is recommended only in special situations, such as in the initial therapy of myxedema and myxedema coma and the short-term suppression of TSH in patients undergoing surgery for thyroid cancer. The use of T3 alone may also be useful in patients with the rare condition of 5 -deiodinase deficiency who cannot convert T4 to T3. 

Myxedema coma, precoma IV Initially, 25-50 mqj( 10-20 meg in patients with cardiovascular disease). Total dose at least 65 meg/day. 

Myxedema coma is an end state of untreated hypothyroidism. It is associated with progressive weakness, stupor, hypothermia, hypoventilation, hypoglycemia, hyponatremia, water intoxication, shock, and death. 

Myxedema coma is a medical emergency. The patient should be treated in the intensive care unit, since tracheal intubation... 

Wartofsky L Myxedema coma. Endocrinol Metab Clin North Am 2006 35 687. [PMID 17127141]... 

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