Myxedema Coma or Crisis Follow-up

• Closely monitor vital signs, electrolytes, and glucose until the levels are within reference ranges and the patient is alert.
• Substitute oral medications for intravenous ones in patients who are extubated and eating.
• Watch for signs of infection, myocardial ischemia, and congestive heart failure.
• Patients who, before hospitalization, did not take their thyroid medication regularly must be evaluated to determine whether they require assistance in taking their thyroid hormone replacement every day.
• Institute physical therapy to assist in strength training and reconditioning.

• Follow-up care is necessary to ensure compliance with thyroid hormone replacement.
• If primary hypothyroidism was diagnosed, assess the TSH level every 6 weeks and adjust the T4 dose. Once a normal TSH level is obtained, it may be monitored yearly. If compliance is an issue, check the patient every 3-6 months.
• In hypothyroidism secondary to pituitary dysfunction, monitor free T4 levels. The TSH level is not an accurate measure of thyroid function.
• Obtain assurance that the precipitants of the initial presentation will not recur.

• Oral levothyroxine is taken daily at least 1 hour before meals.
• If adrenal insufficiency or pituitary dysfunction has been diagnosed, replacement hormones must be taken as appropriate.

• Patients who are awake, no longer dependent on a ventilator, and medically stable may be transferred from the intensive care unit to a medical floor. Before the patient is discharged to return home, transfer to a skilled-care nursing facility for further care and rehabilitation may be necessary.

• Patients with a history of thyroid resection or ablation for hyperthyroidism and persons with a history of Hashimoto thyroiditis are at risk for developing hypothyroidism, and the TSH level should be monitored yearly. Such patients should be informed that hypothyroidism could occur in the future. They should understand the symptoms that signal the condition and the need to seek medical attention for appropriate testing.
• Patients who are likely to be noncompliant with medication regimens must have their thyroid function closely monitored.
• In cold climates, inadequately heated residences are a significant cause of myxedema coma/crises in patients with undiagnosed or inadequately treated hypothyroidism.

• Adrenal crisis is a major complication if patients presenting with myxedema coma/crisis also have adrenal insufficiency and are not treated concomitantly with stress doses of intravenous corticosteroids.
• Myocardial infarction can cause myxedema coma/crisis but may also be a complication of intravenous treatment with thyroid replacement hormones in patients whose myocardial function is already precarious.

Observational studies have analyzed the predictors of survival for patients presenting with myxedema coma.

• In a study of 11 patients with myxedema coma in which 7 survived, statistically significant factors correlated with survival included the following^[7] :

  • Coma on entry
  • Lower Glasgow Coma Scale
  • High APACHE II score
• The following factors were not significantly correlated with survival:

  • Age
  • Body temperature
  • Heart rate
  • Free T4, TSH
• In a study of 23 consecutive patients presenting with myxedema coma, 11 of whom survived, statistically significant predictors of mortality included the following^[14] :

  • Hypotension and bradycardia at presentation
  • Need for mechanical ventilation
  • Hypothermia that is not responsive to treatment
  • Sepsis
  • Intake of sedatives
  • Lower Glasgow Coma Scale
  • High APACHE II score
  • High Sequential Organ Failure Assessment (SOFA) score. The SOFA score at baseline was most predictive, and a day 3 score of more than 6 was highly predictive of a poor outcome.

• Patients must be counseled regarding the necessity of taking daily thyroid hormone replacement and of being monitored on a regular basis so that their TSH level remains within the normal range.
• Patients with a history of Hashimoto thyroiditis or who have undergone thyroid irradiation or resection should be counseled that hypothyroidism might occur in the future. They should be familiarized with the symptoms that suggest the presence of hypothyroidism and should understand the necessity of seeking prompt medical attention for appropriate testing.
• For excellent patient education resources, visit eMedicine's Endocrine System Center. Also, see eMedicine's patient education articles Thyroid Problems and Myxedema Coma.