In a scenario where a child with Tetralogy of Fallot (TOF) experiences severe cyanosis, which position should the nurse place the child in?

The knee-chest position is the most effective for a child with Tetralogy of Fallot experiencing severe cyanosis because it helps increase systemic vascular resistance. In this condition, oxygenated blood is shunted away from the lungs due to the defects involved, leading to reduced oxygen levels in the blood. By placing the child in a knee-chest position, the increased resistance helps divert the blood flow from the right to the left side of the heart, thereby allowing more blood to reach the lungs for oxygenation.

This position encourages better blood flow to the pulmonary arteries, reducing the shunting of deoxygenated blood and improving oxygenation, which is critical in managing the acute cyanotic episodes associated with TOF. Thus, the knee-chest position serves both therapeutic and physiological purposes in enhancing the child's oxygenation during a cyanotic spell.