Explanation
•With tetralogy of Fallot, there is a ventricular septal defect that causes a right to left shunt. This results in deoxygenated blood entering the systemic circulation.
•When a child squats or is in the knee-chest position, the pressure in the left side of the heart increases, resulting in less deoxygenated blood being shunted to the left side of the heart.
•Next action of the nurse is to administer oxygen and morphine sulfate to reduce oxygen demand and increase oxygen sypply.
•Mechanical ventilation is usually not necessary.