In a child with Tetralogy of Fallot experiencing a cyanotic spell, which maneuver should be used?

In a child with Tetralogy of Fallot experiencing a cyanotic spell, which maneuver should be used?

• A. Place in head-down position
• B. Administer digoxin
• C. Place in knee-chest position
• D. Encourage crying

Answer: (C)

During a cyanotic spell in Tetralogy of Fallot, the main problem is increased right-to-left shunting as pulmonary blood flow drops. The goal is to raise systemic vascular resistance to coax more blood toward the lungs, improving oxygenation. The knee-chest position achieves this by increasing afterload (systemic vascular resistance) and modestly enhancing venous return, which reduces the right-to-left shunt through the VSD and allows more blood to reach the lungs. This change typically leads to a quick rise in arterial oxygen saturation and relief of the spell. Placing the child head-down would not specifically reduce the shunt and can worsen the situation by increasing venous return without addressing the underlying shunt dynamics. Encouraging crying tends to provoke more distress and sympathetic stimulation, which can worsen the spell. Digoxin is not used for acute spell management because it does not rapidly modify the shunt or oxygenation during a tet spell.

During a cyanotic spell in Tetralogy of Fallot, the main problem is increased right-to-left shunting as pulmonary blood flow drops. The goal is to raise systemic vascular resistance to coax more blood toward the lungs, improving oxygenation. The knee-chest position achieves this by increasing afterload (systemic vascular resistance) and modestly enhancing venous return, which reduces the right-to-left shunt through the VSD and allows more blood to reach the lungs. This change typically leads to a quick rise in arterial oxygen saturation and relief of the spell.

Placing the child head-down would not specifically reduce the shunt and can worsen the situation by increasing venous return without addressing the underlying shunt dynamics. Encouraging crying tends to provoke more distress and sympathetic stimulation, which can worsen the spell. Digoxin is not used for acute spell management because it does not rapidly modify the shunt or oxygenation during a tet spell.