During a hypercyanotic tet spell, what is the first priority action for a child diagnosed with tetralogy of Fallot?

During a hypercyanotic tet spell, placing the infant in the knees-to-chest position is the priority action because this position increases systemic vascular resistance, which in turn helps to decrease right-to-left shunting across the ventricular septal defect. This improvement in blood flow can enhance oxygenation and relieve the cyanotic episode.

When a child experiences a tet spell, they are typically facing a sudden increase in hypoxia due to the anatomical defects associated with tetralogy of Fallot, including the presence of a ventricular septal defect and right ventricular outflow tract obstruction. By adopting the knees-to-chest position, the child can help improve the hemodynamics by encouraging better blood flow to the lungs, thus rapidly addressing acute cyanosis that occurs during these episodes.

Other interventions may follow this initial action, such as administering oxygen or medications to calm the child and improve circulation, but establishing this position is crucial in the moment to manage the acute episode effectively. This rapid response can significantly affect the outcome during a hypercyanotic spell.