Intern P.D.Chen1

Thyroid Storm 實習醫師 陳柏達

Thyrotoxicosis and Thyroid Storm Bindu Nayak, MD, Kenneth Burman, MD, Endocrinol Metab Clin N Am 35(2006) 663-686

Harrison's Principles of Internal Medicine Perioperative management of the

thyrotoxic patient Roy W. Langley, MD, Henry B. Burch, MD, Endocrinol Metab Clin N Am 32 (2003) 519–534

Intern P.D.Chen2

Thyroid Storm

Exacerbation of hyperthyroidism Acute, life-threatening, hypermetabolic state Thyroid storm may be the initial

presentation of thyrotoxicosis Less than 10% of hospitalized thyrotoxicosis Mortality: 20-30%

Intern P.D.Chen3

Thyroid Storm – underlying cause

Graves’ disease Solitary, multinodular goitor Hypersecretory thyroid carcinoma Axis related tumor Hyperthyroidism aggravated by iodine

exposure (radiocontrast, Amiodarone)

Intern P.D.Chen4

Thyroid Storm – precipitating event

Systemic insults Discontinuation of antithyroid drug Pseudoephedrine, salicylate use Most common: infection

Intern P.D.Chen5

Thyroid Storm – pathophysiology I

Patients with thyroid storm have relatively higher levels of free thyroid hormones(THs) than patients with uncomplicated thyrotoxicosis, even though total TH levels may not be increased.

Adrenergic receptor activation is a hypothesis. Sympathetic nerves innervate the thyroid gland, and catecholamines stimulate TH synthesis. In turn, increased THs increase the density of beta-adrenergic receptors, thereby enhancing the effect of catecholamines.

Intern P.D.Chen6

Thyroid Storm – pathophysiology II Another theory suggests a rapid rise of hormone levels as the

pathogenic source. A drop in binding protein levels, which may occur postoperatively, might cause a sudden rise in free hormone levels. In addition, hormone levels may rise rapidly when the gland is manipulated during surgery, during vigorous palpation during examination, or from damaged follicles following RAI therapy.

Other proposed theories include alterations in tissue tolerance to THs, the presence of a unique catecholaminelike substance in thyrotoxicosis, and a direct sympathomimetic effect of TH as a result of its structural similarity to catecholamines.

Intern P.D.Chen7

Thyroid Storm – presentation I

Heat intolerance and diaphoresis are common in simple thyrotoxicosis -> hyperpyrexia in thyroid storm.

Extremely high metabolism increases oxygen and energy consumption.

Cardiac findings in thyrotoxicosis -> accelerated tachycardia, hypertension, high-output cardiac failure, and a propensity to develop cardiac arrhythmias.

Intern P.D.Chen8

Thyroid Storm – presentation II

irritability and restlessness in thyrotoxicosis -> severe agitation, delirium, seizures, and coma.

mild elevations of transaminases and simple enhancement of intestinal transport in thyrotoxicosis -> diarrhea, vomiting, jaundice, and abdominal pain

Intern P.D.Chen9

Thyroid Storm- diagnosis A score of 45 or more is

highly suggestive of thyroid storm; a score of 25 to 44 supports the diagnosis; and a score below 25 makes thyroid storm unlikely.Adapted from Burch, HB, Wartofsky, L, Endocrinol Metab Clin North Am 1993; 22:263.

40ºC

37.2 – 37.7ºC

Intern P.D.Chen10

Thyroid Storm - prognosis

The mortality rate due to cardiac failure, arrhythmia, or hyperthermia is as high as 30%, even with treatment.

Thyrotoxic crisis is usually precipitated by acute

illness, surgery (especially on the thyroid), or radioiodine treatment of a patient with partially treated or untreated hyperthyroidism.

Intern P.D.Chen11

Thyroid Storm – treatment I

Medications to halt the synthesis, release, and peripheral effects of thyroid hormone.

Controlling adrenergic symptoms and systemic decompensation with supportive therapy

Intern P.D.Chen12

Thyroid Storm – treatment II

Inhibition of new hormoneThionamide (PTU, MMI)

Inhibition of hormone releaseIodinePotassium iodide, Lugol’s solution, iopanoic acidLithium carbonate

Inhibition of T4-to-T3 conversionPTUCorticosteroidsIopanoic acid, amiodaroneBeta-adrenergic blockadePropranolol

Antiadrenergic agentsReserpineGuanethidine

Removal of excess circulating hormonePlamapheresisCharcoal plasmaperfusion

Intern P.D.Chen13

Thyroid Storm – treatment III

Thionamides interfere with thyroperoxidase-catalyzed coupling, and inhibitory effect on thyroid follicular cell function and growth

Thiouracil (propylthiouracil)

v.s. imidazoles (methimazole, carbimazole) SE: abnormal taste, pruritus, urticaria, fever,

arthralgia; agranulocytosis, hepatotoxicity, vasculitis

Intern P.D.Chen14

Thyroid Storm – treatment IV

Thionamides interfere with thyroperoxidase-catalyzed coupling, and inhibitory effect on thyroid follicular cell function and growth

Thiouracil (propylthiouracil)

v.s. imidazoles (methimazole, carbimazole) SE: abnormal taste, pruritus, urticaria, fever,

arthralgia; agranulocytosis, hepatotoxicity, vasculitis

Intern P.D.Chen15

Thyroid Storm – treatment V

Large doses of propylthiouracil (600mg loading

dose and 200 to 300 mg every 6 h) orally or per rectum;

One hour after the first dose of propylthiouracil, stable iodide is given to block thyroid hormone synthesis via the Wolff-Chaikoff effect : saturated solution of potassium iodide (5 drops SSKI every 6

h), or ipodate or iopanoic acid (0.5 mg every 12 h), may be given orally. (Sodium iodide, 0.25 g intravenously every 6 h is an alternative but is not generally available.)

Intern P.D.Chen16

Thyroid Storm – treatment VI

Propranolol should also be given to reduce tachycardia and other adrenergic manifestations (40 to 60 mg orally every 4 h; or 2 mg intravenously every 4 h).

Additional therapeutic measures include glucocorticoids (e.g., dexamethasone, 2 mg every 6 h), antibiotics if infection is present, cooling, oxygen, and intravenous fluids.

Intern P.D.Chen17

Thyroid Storm – operation consideration

Dr. PlummerPhysician, scientist, architect and engineer, Dr. Henry Plummer has rightly been called "a diversified genius."

E.B. Astwood, May 8, 1943:

Treatment of hyperthyroidism with thiourea and thiouracil.

8%-20% mortality in the past

1% with pre-op inorganic iodine

Intern P.D.Chen18

Thyroid Storm – operation considerationAbsolute indicationsFailed medical therapySevere reaction to antithyroidal drugs and not a candidate forradioablation therapyPersistent thyrotoxicosis despite maximum antithyroidal drugtherapy or repeated radioablation treatmentsUnderlying thyroid cancerSuspicious or malignant nodules on FNA

Relative IndicationsSymptomatic goitersPregnancySevere Graves’ ophthalmopathyRefractory thyroiditisAmiodarone relatedNonremitting subacute thyroiditisToxic adenomaRapid control of symptoms requiredAversion to antithyroidal drugs and radioablation therapy

Intern P.D.Chen19

Thyroid Storm – pre-operation consideration

A combination of targets in the thyroid hormone synthetic, secretory and peripheral action pathways.

Concurrent treatment to reverse any decompensation of normal homeostatic mechanisms

Intern P.D.Chen20

Thyroid Storm – pre-operation rapid preparation

Beta-adrenergic blockade Thionamide Oral cholecystographic agents Cortiosteroid

Continue after operation?

Intern P.D.Chen21

Thyroid Storm – post-operation consideration

Keep regimen after resolution of thyrotoxicity

Monitor thyroid hormones

To render the patient as close as possible to clinical and biochemical euthyroidism

Intern P.D.Chen22

Thyroid Storm- Take home message

A score of 45 or more is highly suggestive of thyroid storm

High fever

Conscious change

Intern P.D.Chen23

Thanks you for attention

﹝Rembrandt van Rijn 1606 ~ 1669﹞﹝ ﹞