Thyroid Storm in Hyperemesis Gravidarum

Introduction to Thyroid Storm

Hyperemesis gravidarum can cause biochemical hyperthyroidism, which rarely requires treatment but can progress to life-threatening thyroid storm, according to the American Academy of Family Physicians 1, 2

The American Academy of Family Physicians recommends clinical diagnosis of thyroid storm based on specific criteria, including fever with tachycardia out of proportion to the fever 1, 4
Altered mental status, such as nervousness, restlessness, confusion, or seizures, is a key diagnostic criterion for thyroid storm, as stated by the American Academy of Family Physicians 1, 5
Vomiting and diarrhea beyond typical hyperemesis are also indicative of thyroid storm, according to the American Academy of Family Physicians 1, 6
Cardiac arrhythmia or signs of heart failure are critical diagnostic factors for thyroid storm, as noted by the American Academy of Family Physicians and Praxis Medical Insights 1, 3

The American College of Obstetricians and Gynecologists and Praxis Medical Insights recommend initiating thionamide therapy with propylthiouracil (PTU) as the first-line agent, as it blocks both thyroid hormone synthesis and peripheral T4 to T3 conversion 2, 3
Administering dexamethasone 2 mg IV every 6 hours is crucial to reduce peripheral T4 to T3 conversion and address potential adrenal insufficiency, as stated by Praxis Medical Insights 2, 3
Giving propranolol 60-80 mg orally every 4-6 hours as the first-line beta-blocker is essential, as it also blocks peripheral T4 to T3 conversion, according to Praxis Medical Insights 2, 3

The American College of Obstetricians and Gynecologists recommends monitoring fetal status with ultrasound, nonstress testing, or biophysical profile based on gestational age, and avoiding delivery during thyroid storm unless absolutely necessary 1, 2, 3
Untreated thyroid storm poses severe risks, including maternal heart failure, preeclampsia, preterm delivery, miscarriage, and intrauterine fetal demise, as noted by Praxis Medical Insights 2

The American Academy of Family Physicians and Praxis Medical Insights advise against delaying treatment waiting for thyroid function tests, as clinical diagnosis is sufficient 1, 2, 3
Never administer iodine before thionamides, as this provides substrate for new hormone synthesis, according to Praxis Medical Insights 2
The American Academy of Family Physicians and Praxis Medical Insights recommend against using radioactive iodine (I-131) during pregnancy, as it is absolutely contraindicated and causes fetal thyroid ablation 1, 2