An 8-month-old infant has a hyper-cyanotic Tet spell while blood is being drawn. Which of the following should the nurse's first action be?

A. Preparing the family for imminent death is premature and inappropriate as the first action. Hyper-cyanotic spells (Tet spells) are medical emergencies but often reversible with prompt intervention. B. CPR is not the first response unless the child is unresponsive and pulseless. Tet spells are managed with specific interventions to reduce hypoxia. C. Assessing for neurological defects may be important later, but during an acute Tet spell, the priority is to restore oxygenation and stabilize the child. D. The first action during a Tet spell is to administer oxygen to reduce pulmonary vasoconstriction and improve oxygenation. This is often followed by placing the child in a knee-chest position, giving morphine, and preparing for further medical support as needed. Oxygen is the most immediate, non-invasive intervention.