Thyroid Emergencies

posted in Endocrinology on by
Thyroid Emergencies
SimWars

This post is part of a series developed in preparation for participation in ACEP SimWars. It contains a review of several prominent emergency medicine topics which may be relevant for board preparation. Unless otherwise cited, content is based on HippoEM videos.

Hyperthyroidism

Symptoms

Constitutional Weight loss, heat intolerance, perspiration
Cardiopulmonary Palpitations, chest pain, dyspnea
Neuropsychiatric Tremor, anxiety, double vision, muscle weakness
Neck Fullness, dysphagia, dysphonia
Musculoskeletal Extremity swelling
Reproductive Irregular menses, decreased libido, gynecomastia

Table of contents

  1. Hyperthyroidism
  2. Thyroid Storm
  3. Hypothyroidism
  4. Myxedema Coma
  5. Interpretation of TFT’s

Signs

Vital signs Tachycardia, widened pulse pressure, fever
Cardiovascular Hyperdynamic precordium, CHF, atrial fibrillation, systolic flow murmur
Ophthalmologic Widened palpebral fissure, periorbital edema, proptosis, diplopia, restricted superior gaze
Neurologic Tremor, hyperreflexia, proximal muscle weakness
Dermatologic Palmar erythema, hyperpigmented plaques or non-pitting edema of tibia
Neck Enlarged or nodular thyroid

Causes

  • Grave disease
    • Mechanism: thyroid-stimulating antibodies
    • Female > Male (10x)
    • Findings: ophthalmopathy (lid lag), infiltrative dermopathy (pretibial)
  • Toxic adenoma, toxic multinodular goiter
    • Mechanism: Excess thyroid hormone production
  • Thyroiditis
    • Mechanism: inflammation results in increased thyroid hormone release, typically followed by depletion and TSH suppression resulting in hypothyroidism
    • Signs/symptoms: tachycardia, weight loss, irritability, sweating, anxiety, heat intolerance
    • Subacute thyroiditis
      • Post-viral
      • Symptoms: hoarseness, dysphagia, painful thyroid
    • Hashimoto
      • Typically hypothyroidism
    • Drug-induced: Lithium, amiodarone
    • Trauma: surgical, direct

Thyroid Storm

  • Essentially an exaggeration of thyrotoxicosis featuring marked hyperthermia (104-106°F), tachycardia (HR > 140bpm), and altered mental status (agitation, delirium, coma).
  • Precipitants
    • Medical: Sepsis, MI, CVA, CHF, PE, visceral ischemia
    • Trauma: Surgery, blunt, penetrating
    • Endocrine: DKA, HHS, hypoglycemia
    • Drugs: Iodine, amiodarone, inhaled anesthetics
    • Pregnancy: post-partum, hyperemesis gravidarum
  • Scoring (Burch, Wartofsky)
  • Management
    • Supportive measures
      • Volume resuscitation (with MVI, Thiamine) and cooling
      • Benzodiazepines for agitation
    • Beta-blockade
      • Propranolol 60-80mg PO q4h
      • Propranolol 0.5-1.0mg IV, repeat q15min then 1-2mg q3h
      • Esmolol continuous infusion
    • MTZ/PTU 1-hour prior to iodine
      • Methimazole 20mg (except pregnancy)
      • Propylthiouracil 600mg (hepatotoxic)
    • Steroids: dexamethasone
    • Iodine
    • Endocrinology consultation

Hypothyroidism

Symptoms

Constitutional Weight gain, cold intolerance, fatigue
Cardiopulmonary Dyspnea, decreased exercise capacity
Neuropsychiatric Impaired concentration and attention
Musculoskeletal Extremity swelling
Gastrointestinal Constipation
Reproductive Irregular menses, erectile dysfunction, decreased libido
Integumentary Coarse hair, dry skin, alopecia, thin nails

Signs

Vital signs Bradycardia, hypothermia
Cardiovascular Prolonged QT, increased ventricular arrhythmia, accelerated CAD, diastolic heart failure, peripheral edema
Neurologic Lethargy, slowed speech, agitation, seizures, ataxia/dysmetria, mononeuropathy, delayed relaxation of reflexes
Musculoskeletal Proximal myopathy, pseudohypertrophy, polyarthralgia
Gastrointestinal Ileus

Causes

  • Hashimoto: auto-antiboids
  • Thyroidectomy
  • Radiation, radioactive iodine ablation

Myxedema Coma

  • Precipitants
    • Critical illness: sepsis (especially PNA), CVA, MI, CHF, trauma, burns
    • Endocrine: DKA, hypoglycemia
    • Drugs: amiodarone, lithium, phenytoin, rifampin, medication non-adherence
    • Environmental: cold exposure
  • Recognition
    • History: hypothyroidism, thyroidectomy scar and acute precipitating illness
    • Hypothermia: temp <95.9°F (or normal in presence of infection)
    • AMS: lethargy, confusion, coma, agitation, psychosis, seizures
    • Hypotension: refractory to volume resuscitation and pressors
    • Bradypnea: with hypercapnia and hypoxia
    • Skin: non-pitting edema of face and hands
    • Hyponatremia
  • Management
    • Airway protection
    • Fluid resuscitation
    • Thyroid hormone replacement
      • Young, otherwise healthy patients: T3 10ug IV q4h
      • Elderly, cardiac compromise: 300ug IV x1
      • Steroids: dexamethasone 1h prior to thyroid hormone
    • Treat precipitating illness

Interpretation of Thyroid Function Tests

Condition TSH T4
None Normal Normal
Hyperthyroidism Low High
Hypothyroidism High Low
Subclinical hyperthyroidism Low Normal
Subclinical hypothyroidism High Normal
Sick euthyroid Low Low