Final answer:
CPAP therapy is appropriate for a spontaneously breathing baby with unlabored breathing but a heart rate <100 bpm. It supports breathing in infants with RDS, and helps prevent severe consequences of untreated sleep apnea, including SID risk.
Step-by-step explanation:
The appropriate instance to begin nasal continuous positive airway pressure (CPAP) therapy is for a baby who is breathing spontaneously and unlabored with a heart rate that is less than 100 beats per minute (bpm).
CPAP is often applied if spontaneous breathing occurs and the infant is showing signs of respiratory distress but does not require more invasive methods like mechanical ventilation. CPAP can also be a next step in treatment if the baby is initially placed on Positive Pressure Ventilation (PPV) and then stabilizes with an adequate heart rate but still requires respiratory support. It is important in managing conditions like Respiratory Distress Syndrome (RDS) and preventing the serious consequences of untreated sleep apnea, including the risk of sudden infant death (SID). Other supportive therapies may also be administered to assist with the baby's overall stabilization and care.