Final answer:
The single most important and most effective step in neonatal resuscitation is ventilating the lungs to enable oxygen exchange and reduce lung pressure, especially when dealing with conditions like RDS. Pulmonary surfactant therapy has significantly reduced associated mortality rates.
Step-by-step explanation:
The single most important and most effective step in neonatal resuscitation is ventilating the lungs. This critical intervention occurs when a newborn does not begin to breathe on their own immediately following birth. Ventilation is key to decreasing lung pressure and resistance to blood flow, allowing for the pulmonary alveoli to open and fill with blood, enabling gas exchange and the intake of oxygen. The introduction of pulmonary surfactant therapy has notably decreased the mortality rate associated with Respiratory Distress Syndrome (RDS) by 50%. The presence of surfactant reduces surface tension within the alveoli, crucial for successful lung inflation. If an infant breathes spontaneously, nasal continuous positive airway pressure (CPAP) may be applied to assist breathing, alongside other supportive therapies such as temperature control, nutritional support, and antibiotics if necessary.