Problems that need to identified and treated include:
(1) thyroid hormone deficiency
(2) hypothermia
(3) cardiac and respiratory dysfunction
(3) concurrent metabolic disorders
(4) therapy of precipitating cause
Thyroid hormone replacement for deficiency involves administration of thyroxine (T4).
(1) Thyroxine is given intravenously at first, then orally when tolerated.
(2) The initial IV dose of levothyroxine is 100 to 500 micrograms, followed by daily IV doses of 75 - 100 micrograms.
(3) A patient with significant comorbidities (frailty, cardiovascular disease, other) should receive doses at the lower end of the dosage range.
(4) Once the GI tract is functioning adequately, oral dosing replaces IV dosing. with a daily oral dose in the range of 100 to 170 micrograms.
A hypothermic patient should be covered with regular blankets. The use of warming blankets can result in peripheral vasodilation which can precipitate cardiovascular collapse.
Blood pressure and cardiovascular status should be monitored. Pressors and positive inotropes should be avoided if possible because of the risk of cardiac arrhythmias during intravenous thyroxine therapy.
Respiratory disorders may include hypoventilation and hypercarbia. Mechanical ventilation may be required.
Metabolic disorders may include:
(1) dehydration
(2) hyponatremia
(3) hypoglycemia
Adrenal insufficiency may be present, and corticosteroids should be administered until this has been ruled out.
(1) 100 mg hydrocortisone is given IV every 8 hours.
(2) Testing of adrenal function may include a random serum cortisol or an adrenocorticotropin hormone stimulation test.
Therapy of underlying causes may include:
(1) antibiotics if the patient has evidence of infection
(2) discontinuation of implicated medications if possible
(3) control of hemorrhage with blood replacement
