Thyroid Storm

Thyroid storm (thyrotoxic crisis) is a life-threatening exacerbation of thyrotoxicosis with multisystem decompensation. The massive excess of thyroid hormones (T3 and T4) increases beta-adrenergic receptor sensitivity and density, amplifying catecholamine effects on the heart (tachycardia, arrhythmias, high-output heart failure), vasculature (systolic hypertension, widened pulse pressure), and CNS (agitation, psychosis, seizures, coma). T3 directly increases basal metabolic rate by uncoupling oxidative phosphorylation and upregulating Na+/K+-ATPase activity in virtually all tissues, generating massive heat production (hyperthermia up to 41°C). Hepatic dysfunction occurs from direct thyroid hormone hepatotoxicity and hepatic congestion from high-output cardiac failure. The precipitant (infection, surgery, iodine load, abrupt antithyroid drug discontinuation) overwhelms already-stressed physiological compensatory mechanisms. The Burch-Wartofsky Point Scale (BWPS ≥ 45 = thyroid storm, 25-44 = impending storm) guides clinical diagnosis based on thermoregulatory dysfunction, CNS effects, GI-hepatic dysfunction, cardiovascular dysfunction, and precipitant history.