Neonatal Respiratory Distress Syndrome (RDS)

Ask about antenatal steroids - reducing incidence and severity with antenatal corticosteroids is the first goal of management, so find out whether and when a course was given before you take a preterm neonate to the OR.

Confirm the picture - chest film shows homogenous diffuse atelectasis with a ground-glass reticulogranular appearance, air bronchograms, and low lung volumes. ABG shows hypoxemia that responds to added oxygen, hypercapnia, and on serial gases a worsening respiratory and metabolic acidosis with lactic acidemia.

The look at the bedside - tachypnea, expiratory grunting, nasal flaring, subcostal, intercostal and suprasternal retractions, accessory muscle use, cyanosis, poor perfusion, and uniformly decreased air entry. Untreated, it worsens over 48 to 72 hours to lethargy and apnea.

Keep the differential open - transient tachypnea of the newborn, pneumothorax and pneumomediastinum, neonatal pneumonia, meconium aspiration, persistent pulmonary hypertension of the newborn (PPHN), and cyanotic congenital heart disease all present the same way.

Surfactant is the targeted therapy - intratracheal replacement within 30 to 60 minutes of birth hastens recovery and cuts pneumothorax, interstitial emphysema, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), and mortality. European consensus triggers administration at FiO2 > 0.3 in immature babies and FiO2 > 0.4 in mature ones. Expect bradycardia, hypotension, and desaturation during instillation, and watch the ETT for transient obstruction.

CPAP first, then escalate - early nasal CPAP with selective surfactant is the preferred strategy; targets are SpO2 90-95% and PaCO2 45-65 mmHg. Intubate for pH < 7.2 with PaCO2 > 60-65 mmHg, PaO2 < 50 mmHg or FiO2 > 0.40 on CPAP, or severe apnea. Time-cycled pressure-limited ventilation is the usual initial mode; HFOV and HFJV are rescue.

Arterial targets - PaO2 50-80 mmHg, PaCO2 40-55 mmHg, pH above 7.25, drawn from an umbilical or peripheral arterial catheter.

Don't chase a high saturation - PaO2 can be far higher than you think at SpO2 above 95%, and oxidative stress from high oxygen tension inactivates surfactant and feeds BPD and retinopathy.

Air leak is the ventilator's price - overdistension in a stiff atelectatic lung causes pneumothorax, pneumomediastinum, and pulmonary interstitial emphysema. Sudden desaturation with hemodynamic decline on positive pressure points there first.

Look for the ductus - echocardiogram identifies a patent ductus arteriosus, whose incidence is increased in very low birth weight infants with RDS and which complicates the course.

Caffeine for the small preemie - caffeine raises respiratory drive and supports CPAP in infants under 28 weeks or under 1000 g, with less BPD and earlier extubation.

Supportive basics still decide outcomes - thermoregulation at 36.5 to 37.5 C, careful fluid and electrolyte management, crystalloid and vasopressors for hypotension, and transfusion for anemia.

Neonatal respiratory distress syndrome (RDS) is surfactant deficiency in an immature lung — either too little surfactant produced or surfactant inactivated once it is there. Type 2 pneumocytes begin producing surfactant in the second trimester and reach mature levels near 35 weeks, so incidence tracks inversely with gestational age: about 98% of infants born at 24 weeks, 5% at 34 weeks, and under 1% at 37 weeks. Prematurity and low birth weight dominate the risk; maternal diabetes, male sex, white race, perinatal hypoxia, and delivery in the absence of labor add to it.

By Laplace (P = 2T/R), rising surface tension raises the pressure needed to hold an alveolus open, compliance falls, and the lung atelectases diffusely. Repeated collapse injures the epithelium, drives a cytokine response, and floods alveoli with protein-rich fluid that inactivates whatever surfactant remains. The result is shunt, hypoxemia, and lactic acidemia.