Newborn respiratory adaptation is the shift from placenta-supported oxygenation to independent lung gas exchange. The first breaths clear fetal lung fluid, expand alveoli, lower pulmonary vascular resistance, and increase pulmonary blood flow. If fluid clearance, surfactant function, perfusion, or airway patency is impaired, the newborn may look only mildly stressed before oxygenation declines. The RN learner must connect work of breathing with color, tone, temperature, feeding stamina, and response to positioning because respiratory transition is never assessed by rate alone.