CURRENT Essentials of Critical Care.pdf

186 Current Essentials of Critical CareThyroid Storm■ Essentials of Diagnosis• Heat intolerance, nervousness, increased number of bowelmovements, increased appetite, weight loss, thinning of hair andskin, sweating, weakness• Confusion, agitation, overt psychosis, coma• Fever due to breakdown of thermoregulatory system• Cardiovascular manifestations: tachycardia, atrial fibrillation,hypertension, widened pulse pressure, congestive heart failure;hypotension late manifestation• Ophthalmopathy, dermopathy, thyroid bruit with Graves disease• Warm, moist, flushed, soft “velvety” skin; tremor; brisk tendonreflexes; proximal myopathy; generalized cachexia• Goiter almost always present• Elevated T 4 and T 3 typically seen; nearly undetectable TSH• Elevated aminotransferases, hyperbilirubinemia, alkaline phosphatase(bone fraction), calcium• Uncontrolled or poorly controlled hyperthyroidism with precipitatingevent: surgical procedure, infection, cardiovascular disease,diabetic ketoacidosis, stroke, trauma, anesthesia, administrationof iodinated contrast material■ Differential Diagnosis• Sepsis • Pheochromocytoma• Acute psychiatric illness • Levothyroxine overdose• Toxic ingestion • Alcohol withdrawal■ Treatment• Identify and treat precipitating event• Reduce thyroid hormone synthesis or peripheral conversion ofT 4 to T 3 using thiourea (propylthiouracil or methimazole) followedby ipodate sodium (iodine-containing contrast agent)• Inhibit release of thyroid hormone with iodide (sodium iodideor Lugol solution); lithium if intolerant of iodine• Sympathetic blockade with propranolol; also weakly inhibits peripheralconversion of T 4 to T 3• Glucocorticoids inhibit TSH secretion, lower T 4 levels; also usein those with suspected adrenal insufficiency• Correct hyperthermia, hypovolemia, electrolyte abnormalities■ PearlAvoid salicylates in the management of hyperthermia in thyroid stormas they can displace thyroid hormone from its binding sites and worsenthis hyperthyroid state.ReferenceTietgens ST et al: Thyroid storm. Med Clin North Am 1995;79:169. [PMID:7808090]