Maximum FiO2 Delivered by Oxygen Hood in Neonates
An oxygen hood can deliver up to 100% FiO2 (1.0) to neonates when properly used with adequate flow rates.
Oxygen Hood Delivery System
Oxygen hoods are a type of face tent or head hood delivery system specifically designed for neonates who require supplemental oxygen. They function by creating an oxygen-enriched environment around the infant's head while allowing for:
- Precise control of oxygen concentration
- Adequate humidification
- Visibility of the patient
- Access for feeding and care
Advantages and Limitations
Advantages:
- Ability to deliver high FiO2 (up to 100%)
- Enhanced humidification capabilities
- No need for direct attachment to the infant
- Allows for visual assessment of the infant
Limitations:
- Carbon dioxide can build up with insufficient flow rates 1
- Temperature and moisture buildup can be problematic 1
- Limited mobility for the infant
- Potential for reduced visibility of the patient 1
Technical Considerations for Maximum FiO2 Delivery
To achieve maximum FiO2 (up to 100%) with an oxygen hood, several factors must be optimized:
Flow Rate: Adequate flow rates (typically 5-10 L/min) are essential to:
- Prevent carbon dioxide accumulation
- Maintain the desired oxygen concentration
- Compensate for leakage around the hood
Proper Fit: The hood must create an appropriate seal around the infant's neck while avoiding pressure or constriction.
Humidification: The American Heart Association recommends humidifying oxygen to prevent mucosal drying and thickening of pulmonary secretions 1.
Clinical Considerations for Oxygen Therapy
While oxygen hoods can deliver up to 100% FiO2, current guidelines recommend a more measured approach to oxygen therapy in neonates:
- The American Academy of Pediatrics recommends starting with lower oxygen concentrations (21-30%) rather than higher (60-100%) and titrating based on pulse oximetry 2
- For most neonates, target oxygen saturation should be maintained between 90-95% 2
- For extremely preterm infants at risk of retinopathy of prematurity, more careful oxygen targeting is required 2, 3
Monitoring and Safety
When using an oxygen hood to deliver high FiO2:
Continuous Monitoring: Use pulse oximetry to monitor oxygen saturation and adjust FiO2 accordingly.
Avoiding Hyperoxia: The American Heart Association recommends weaning FiO2 for saturations of 100% to avoid hyperoxia while maintaining saturation ≥94% 1.
Flow Adequacy: Ensure sufficient flow to prevent carbon dioxide buildup within the hood.
Alternative Oxygen Delivery Methods
While oxygen hoods can deliver maximum FiO2, other delivery methods for neonates include:
- Nasal Cannula: Most widely used and preferred for stable neonates, but limited in maximum FiO2 delivery (typically 30-50% depending on flow rate and infant size) 1, 2
- Simple Oxygen Masks: Can provide 30-50% oxygen to spontaneously breathing patients 1
- Non-rebreathing Masks: Can deliver higher concentrations with appropriate flow rates (approximately 15 L/min) 1
Conclusion
While oxygen hoods can technically deliver up to 100% FiO2 to neonates, current practice emphasizes starting with lower oxygen concentrations and titrating based on oxygen saturation targets to minimize potential oxygen toxicity while ensuring adequate tissue oxygenation.