In an extremely low‑birth‑weight infant (<1000 g, ≤28 weeks gestation) with apnea of prematurity, how should continuous positive airway pressure (CPAP) be used and managed?

CPAP Management in ELBW Infants with Apnea of Prematurity

For extremely low-birth-weight infants (<1000 g, ≤28 weeks gestation) with apnea of prematurity, initiate CPAP at 5-6 cm H₂O as first-line respiratory support, combined with caffeine therapy (target serum level 5-20 mg/L), and escalate to mechanical ventilation only if the infant fails CPAP based on specific clinical criteria.

Initial CPAP Application

Begin nasal CPAP immediately at 5-6 cm H₂O for spontaneously breathing ELBW infants showing signs of respiratory distress or apnea. 1 This pressure setting maintains functional residual capacity and reduces the combined risk of bronchopulmonary dysplasia or death compared with routine intubation. 1

Equipment Selection

• Use bubble CPAP, ventilator CPAP, or T-piece resuscitator systems, all of which have been validated in large randomized trials. 2
• Ensure PEEP-capable devices are available, including self-inflating bags with PEEP valves, flow-inflating bags, or T-piece resuscitators. 1
• Avoid high PEEP levels (8-12 cm H₂O), as these may reduce pulmonary blood flow and increase pneumothorax risk. 2

Pharmacologic Management

Initiate caffeine citrate concurrently with CPAP for all ELBW infants with apnea of prematurity. 3, 4 Caffeine is preferred over theophylline due to its wider therapeutic index and lower adverse effect profile. 3

Caffeine Dosing and Monitoring

• Target serum caffeine concentrations between 5-20 mg/L. 3
• Monitor for toxicity signs including tachycardia (typically at levels ≥13 mg/L), gastroesophageal reflux, irritability, and altered sleep patterns. 3
• Maintain continuous heart rate monitoring, as bradycardia often accompanies apneic episodes. 3

Criteria for CPAP Failure and Escalation

Escalate to mechanical ventilation with surfactant administration when any of the following occur:

• FiO₂ requirement ≥0.30-0.50 to maintain target oxygen saturations (88-93%) despite adequate CPAP 1, 5
• Persistent or worsening work of breathing with continued grunting and retractions 1
• Recurrent apnea unresponsive to caffeine and CPAP 4, 6
• Heart rate persistently <100 bpm despite adequate respiratory support 7
• Inadequate gas exchange with persistent hypoxemia or hypercarbia 7

Surfactant Administration Strategy

Use selective surfactant administration rather than prophylactic dosing. 2, 1 When CPAP fails and intubation is required, administer surfactant followed by rapid extubation back to CPAP (INSURE technique). 1, 7 This approach reduces subsequent mechanical ventilation needs (RR 0.67; 95% CI 0.57-0.79) compared with delayed rescue surfactant. 1

Expected Outcomes in ELBW Population

In ELBW infants <28 weeks gestation or <1000 g, expect 40-90% to require mechanical ventilation despite CPAP initiation. 2 Approximately 50% of extremely preterm infants initially managed with CPAP ultimately require surfactant administration. 7 In the 25-28 week gestation range specifically, CPAP reduces mechanical ventilation rates from 100% to 46% and surfactant use from 77% to 38% compared with routine intubation. 2

Critical Pitfalls to Avoid

• Do not delay CPAP initiation while waiting for apnea to resolve spontaneously, as untreated apnea of prematurity may be associated with negative outcomes including hypoxia and death. 4, 6
• Avoid starting with 100% oxygen for initial resuscitation; begin with 21-30% oxygen and titrate upward based on pulse oximetry. 1
• Do not use prophylactic surfactant in spontaneously breathing infants on CPAP, as this increases the risk of death or chronic lung disease (RR 1.13; 95% CI 1.02-1.25). 1
• Monitor for pneumothorax, which occurs in 9% of CPAP-treated infants versus 3% with intubation in the 25-28 week population. 2
• Avoid excessive ventilation pressures if escalation to positive pressure ventilation is needed; start with 20-25 cm H₂O and titrate based on chest rise and heart rate response. 2, 7

Ongoing Management

Continue CPAP and caffeine therapy until complete resolution of apnea occurs, then wean gradually rather than abruptly. 3, 8 Maintain target oxygen saturations between 88-93% throughout treatment. 5 For infants requiring prolonged therapy, close monitoring is essential, and some may require home apnea monitors after discharge. 8