Prehospital Oxygen Delivery for Neonates
In the prehospital setting, begin oxygen delivery based on gestational age: use 21% oxygen (room air) for term/late preterm neonates ≥35 weeks, 21-30% oxygen for preterm neonates 32-34 weeks, and 30-100% oxygen for extremely preterm neonates <32 weeks, while placing a pulse oximeter on the right hand/wrist immediately to titrate oxygen to target saturations. 1
Device Selection and Oxygen Delivery
Initial Oxygen Concentration by Gestational Age
The 2025 AHA/AAP guidelines provide clear stratification 1:
- Term and late preterm (≥35 weeks): Start with 21% oxygen (room air)
- Moderate preterm (32-34⁶/₇ weeks): Start with 21-30% oxygen
- Extremely preterm (<32 weeks): Start with 30-100% oxygen
This gestational age-based approach is critical because extremely preterm infants who fail to reach 80% oxygen saturation by 5 minutes have significantly increased mortality risk, regardless of initial oxygen concentration. 1 Starting with 21-30% oxygen in infants <32 weeks may be insufficient to achieve target saturations and prevent death. 1
Pulse Oximetry Placement
Place the pulse oximeter sensor on the right hand or wrist (preductal position) as soon as possible - this reflects oxygen saturation to the myocardium and brain. 1 Expect delays in obtaining readings: median time is 238 seconds in resuscitated infants, and longer (260 seconds) in asphyxiated infants compared to healthy controls (100 seconds). 1 Preterm infants take even longer to achieve reliable readings than term infants. 1
Oxygen Titration Strategy
Oxygen supplementation must be titrated to target saturation goals - this is a Class 1 recommendation with expert consensus. 1 The targets are based on normal transition values in healthy term infants, aiming to avoid both hypoxia and hyperoxia. 1 While optimal saturation targets during resuscitation remain unknown, current practice uses preductal saturation ranges measured in healthy newborns. 1
For extremely preterm infants specifically, target SpO₂ of 80% by 5 minutes of life, as failure to achieve this is associated with death. 1 Consider increasing FiO₂ by 10-20% every 30 seconds if targets are not being met. 2
Device Options in Prehospital Settings
Ventilation Devices
If positive pressure ventilation is needed, T-piece resuscitators are superior to self-inflating bags for preterm infants, reducing bronchopulmonary dysplasia, intubation requirements, and duration of mechanical ventilation. 1 However, in prehospital settings where T-piece devices may be unavailable, self-inflating bags with oxygen reservoir are acceptable alternatives.
Blow-by Oxygen Limitations
Avoid blow-by oxygen methods in prehospital transport - laboratory studies demonstrate that blow-by methods fail to maintain FiO₂ >50% at distances of 5 cm from the face, with FiO₂ dropping to near room air levels (marginally above 21%) within 6-12 meters of transport initiation, even at flow rates of 10 L/min. 3 Only at 0 cm from the face can most blow-by methods maintain adequate oxygen delivery. 3
Critical Pitfalls to Avoid
Hyperoxia Risks
Do not use 100% oxygen for term infants - meta-analyses show that starting with 100% oxygen versus 21% oxygen increases short-term mortality in term and late preterm infants. 1 Both hyperoxia and hypoxia cause harm through oxidative stress and tissue injury. 4, 5
Hypoxia in Extremely Preterm Infants
Do not start with room air alone in infants <32 weeks gestation - these infants develop early hypoxia and bradycardia with low oxygen concentrations, leading to higher rates of severe intraventricular hemorrhage and death. 2 The ILCOR 2025 consensus recommends starting with ≥30% oxygen for this population. 6
Prolonged Bradycardia
Heart rate <100 bpm for >2 minutes is associated with increased adverse outcomes including death. 7 If bradycardia persists despite adequate ventilation, increase FiO₂ while ensuring effective positive pressure ventilation.
Practical Algorithm for Prehospital Providers
- Assess gestational age immediately
- Apply pulse oximeter to right hand/wrist (don't wait for reading to start oxygen)
- Initiate oxygen based on gestational age (21%, 21-30%, or 30-100%)
- Monitor heart rate continuously - maintain >100 bpm
- Titrate FiO₂ every 30 seconds based on pulse oximetry readings when available
- Target SpO₂ of 80% by 5 minutes for extremely preterm infants
- Increase FiO₂ by 10-20% increments if targets not met or bradycardia persists
The prehospital environment poses unique challenges with limited equipment and monitoring capabilities 4, but adherence to these gestational age-based starting points with rapid pulse oximetry placement provides the best balance between preventing hypoxic injury and avoiding hyperoxic damage. 1, 6