Overview
Stabilise a newborn with respiratory compromise, use gestation, timing and physiology to distinguish common causes, and escalate oxygen, non-invasive support, surfactant, ventilation and cause-specific treatment safely.
Breathing difficulty in a newborn is a final common pathway rather than one diagnosis. Lung immaturity, retained fluid, aspiration, infection, air leak, maladaptation of pulmonary circulation, cardiac disease and congenital anatomy can look similar initially.
At transition, aeration lowers pulmonary vascular resistance and replaces placental gas exchange. Failure of aeration or persistent high pulmonary pressure creates hypoxaemia, bradycardia and right-to-left shunting.
Respiratory distress syndrome is primarily surfactant deficiency in preterm lungs. Increased surface tension collapses alveoli at end-expiration, reduces compliance and functional residual capacity, and produces worsening work of breathing.
Transient tachypnoea reflects delayed absorption of fetal lung fluid, particularly after prelabour caesarean birth. It should improve, whereas worsening oxygen need, shock or systemic illness argues for another cause.