Tet Spell
Acute episodes of severe cyanosis and distress in patients with tetralogy of Fallot, caused by dynamic right ventricular outflow obstruction.
Full Definition
Tet spells, also known as hypercyanotic episodes or blue spells, are acute episodes of severe cyanosis that occur in patients with tetralogy of Fallot. These episodes result from dynamic obstruction of the right ventricular outflow tract, leading to decreased pulmonary blood flow and increased right-to-left shunting. Triggers may include crying, exertion, dehydration, or fever. Treatment includes positioning (knee-chest position), oxygen, morphine, and sometimes beta-blockers or phenylephrine. Frequent or severe tet spells are an indication for urgent surgical repair.
Usage
Usage note: Informal term widely used in pediatric cardiology. Also called hypercyanotic episodes in formal documentation.
In Context
- "The toddler experienced her first tet spell during a crying episode and was scheduled for early surgical repair." — Emergency department visit
- "Parents were educated on positioning techniques to manage tet spells at home." — Discharge planning note