Myxedema Coma

Myxedema coma is the most severe expression of decompensated hypothyroidism. The true incidence is unknown; however, only 200 cases were reported between 1953 and 1986. It is more common in the elderly (70% >60 years of age) and women (80%) and presents almost invariably during winter months (95%). Only approximately a third of patients have a history of hypothyroidism. The diagnosis is often delayed because of the coexistence of a precipitating factor (infection, stroke, hypothermia, sedative-hypnotic use, recent surgery, trauma, or other severe illness), which is presumed to be the cause of the patient's AMS. The diagnosis is then entertained only when initial management fails. Previous mortality was 80%; it is now 15% to 20% principally because of the availability of intravenous levothyroxine.

Causes

If you have hypothyroidism, then any of the following can contribute to myxedema coma:

• Infections, especially lung and urine infections
• Heart failure
• Stroke
• Trauma
• Surgery
• Drugs, such as includes phenothiazines, amiodarone, lithium, and tranquilizers, and prolonged iodide use
• Not taking prescribed thyroid medications

Symptoms

• AMS: lethargy, confusion, or psychosis; often a gradual deterioration over weeks
• Symptoms of hypothyroidism: fatigue, weakness, cold intolerance, muscle cramps, constipation, weight gain

Signs

• Coma +++
• Seizures: ++ in patients with coma
• Hypothermia (T < 35.5° C) ++++ in comatose patients
• Vital signs reflect the state of overall decreased metabolism: bradycardia ++++, SBP <100 +++, hypoventilation (with hypoxemia and hypercarbia).
• Signs of long-standing hypothyroidism: periorbital edema, macroglossia, hoarse voice, dry and cool skin, nonpitting edema of the lower extremities, fine hair texture with diminished eyebrows, and delayed relaxation of deep tendon reflexes
• Many of the signs of myxedema are indicative of a lowered basal metabolic rate and a lack of stimulation of beta-adrenergic receptors.
• Abdominal distention is common from either ileus or constipation; megacolon and fecal impaction can occur.
• Heart sounds are frequently distant due to pericardial effusion +++. Congestive heart failure is also frequent.
• Fever may develop and heart rate can be "normal" if sepsis is also present.

Treatment

If you have hypothyroidism, be alert to your condition.

• Call your doctor if you are concerned.
• Check your blood sugar level if you are diabetic.
• Warm yourself up with a warm blanket and seek help.
• Take your prescribed thyroid medication if you missed them earlier.

Medical Treatment such as includes:

• Intravenous fluids
• Electrolytes replacement as necessary
• Thyroid hormones are usually administered through a vein to quickly correct the low thyroid hormone blood level.
• Cortisol or other adrenal cortical hormone intravenously
• Warming blanket if body temperature is low
• Glucose supplements if the blood sugar level is low