Thyroid Storm

Question 1

What is a thyroid storm?

Answer 1

• It is a rare, life-threatening, hyper-metabolic state due to untreated, or under treated hyperthyroidism
• Classic thyrotoxic symptoms include tachycardia, hyperpyrexia and central nervous system dysfunction

Question 2

What can cause a thyroid storm?

Answer 2

• Acute event, such as subtotal thyroidectomy or non-thyroidal surgery (major stress)
• Trauma
• Infection
• Acute iodine load
• Pregnancy
• Thyroid drug overdose
• Discontinuation of anti-thyroid medications
• Uncontrolled diabetes

Question 3

What are the subjective/physical exam findings associated with a thyroid storm?

Answer 3

Subjective findings:

• Hyperpyrexia – up to 105.8 F (41 C)
• Flushing
• Profuse diaphoresis- fluid losses up to 4 L /24 hours
• Marked tachycardia/palpitations
• CNS dysfunction– mental status changes, agitation, delirium, psychosis, stupor/coma
• Hyper-defecation
• N/vV
• right upper quadrant abdominal pain secondary to liver congestion (due to high output congestive heart failure)

Physical Exam findings may include:

• Lid lag
• Goiter
• Hand tremor
• Warm, moist skin

Question 4

What lab findings are seen in patients in thyroid storm?

Answer 4

Refer to hyperthyroid –thyrotoxic manifestations:

• Suppressed TSH
• Elevated free T4 (thyroxine) and T3 (triiodothyronine)

The diagnosis of thyroid storm is based upon the presence of severe and life-threatening symptoms as mentioned above in a patient with biochemical evidence of hyperthyroidism.

Question 5

How do you manage a patient with thyroid storm pre-operatively?

Answer 5

• Lugol’s iodine solution should be given preoperatively.
  
  • It is an iodine salt which inhibits the release as well as the synthesis of thyroid hormones
  • Iodine salts have a slow onset of action, 2-3 days and the effects are transient.
• Iodine salts are used in the management of thyroid storm, severe thyrotoxicosis and to prepare patients for surgical resection of a hyperactive thyroid

Question 6

In general, outside of the pre-operative environment, how would you pharmacologically manage a patient with thyroid storm?

Answer 6

Anti-thyroid medications (inhibit the SYNTHESIS of thyroid hormones):

• Propylthiouracil 900-1200 mg/day in divided doses OR
• Methimazole 90-120mg/day in divided doses

Medications that inhibit the RELEASE of thyroid hormones (iodine preparations); administered 1 hours after anti-thyroid medications

• Lugol’s (iodine) solution – 10 drops po every 6 hours WITH
• Sodium iodine, 1-gram slow IV, with agents that block the effects of thyroid hormone

Medications that block the effects of thyroid hormones (i.e. Beta-blockers):

• Esmolol 40-80 mg po every 6 hours WITH
• Hydrocortisone 50mg every 6 hours to be tapered rapidly once patient improves

Surgery or treatment with Radioactive Iodine is delayed until the patient becomes euthyroid

Question 7

What antipyretics are used in a patient with thyroid storm?

Answer 7

• Use acetaminophen;
• Avoid use of ASPIRIN or NSAIDS due to potential of interfering with binding of T4 and thyroid binding globulin resulting in exacerbated hyper-metabolism