What are the uses and advantages of an oxygen hood over other oxygen support systems in patients requiring oxygen therapy?

Oxygen Hood: Uses and Advantages Over Other Oxygen Support Systems

Oxygen hoods are effective for delivering high FiO2 levels but are generally not recommended over other oxygen delivery devices for most patients due to practical limitations in consistent oxygen delivery and patient comfort.

Uses of Oxygen Hoods

• Oxygen hoods are primarily used in neonatal and pediatric populations requiring supplemental oxygen therapy 1.
• They can deliver high concentrations of oxygen (FiO2 greater than 0.80) to reduce pulmonary artery pressure in patients with chronic lung disease of infancy (CLDI) 2.
• Oxygen hoods are used for infants who cannot tolerate nasal cannulas or when precise oxygen concentration delivery is required 3.
• They can be used for controlled FiO2 therapy to neonates, though oxygen concentration varies based on hood size, lid position, and flow rate 4.

Advantages of Oxygen Hoods

• Can deliver high oxygen concentrations in a controlled environment 2.
• Avoids direct contact with the face, which may be beneficial for infants with facial trauma or skin sensitivity 3.
• Allows visual assessment of the infant's face and airway without disrupting oxygen delivery 3.
• May be useful for short-term, high-concentration oxygen therapy in specific clinical scenarios 2.

Disadvantages of Oxygen Hoods Compared to Other Oxygen Delivery Systems

• Nasal cannulae are generally preferred over oxygen hoods for consistent oxygenation and improved growth, especially during feeding and handling 2.
• Oxygen hoods are not recommended for consistent oxygen delivery compared to low-flow devices according to the AARC Clinical Practice Guideline 1.
• Oxygen hoods restrict access to the patient and may interfere with feeding, physical examination, and parent-infant bonding 3.
• They require higher oxygen flow rates to maintain stable oxygen concentrations and prevent carbon dioxide retention 4.
• Patient movement can significantly affect the delivered oxygen concentration 3.

Preferred Oxygen Delivery Methods by Clinical Context

For Infants and Children:

• Nasal cannulae are preferred for most infants requiring oxygen therapy because:

  • They provide more consistent oxygenation during feeding and handling 2.
  • They improve growth compared to oxygen hoods 2.
  • They allow greater mobility and parental interaction 3.
  • Flow rates of 0.25 to 3 L/min can achieve similar pulmonary artery pressure reductions as oxygen hoods with FiO2 >0.80 2.

• High-flow nasal cannula (HFNC) is recommended:

  • For infants with moderate to severe bronchiolitis as it's safer and more effective than low-flow oxygen 1.
  • For patients requiring medium to high-concentration oxygen therapy who are not at risk of hypercapnia 2.
  • HFNC is well-tolerated and may provide a CPAP effect while offering greater comfort 2.

For Adults:

• Nasal cannulae are recommended for medium-concentration oxygen therapy because:

  • They are preferred by patients for comfort 2.
  • They are less likely to be removed during meals 2.
  • They offer cost savings compared to other delivery methods 2.
  • Flow rates should be adjusted between 2-6 L/min to achieve desired saturation 2.

• Venturi masks are recommended for patients requiring precise control of FiO2, especially:

  • For those at risk of hypercapnic respiratory failure 2.
  • When a constant FiO2 of 24%, 28%, 31%, 35%, 40%, or 60% is needed 2.
  • For COPD patients with respiratory rates >30 breaths/min 2.

• High-concentration reservoir masks at 15 L/min are preferred for critically ill patients until reliable pulse oximetry monitoring is established 2.

Clinical Decision-Making Algorithm for Oxygen Delivery Method

1. Assess patient age and clinical condition:

   • Infant/child vs. adult
   • Severity of respiratory distress
   • Risk of hypercapnic respiratory failure 2

2. For infants and children:

   • First-line: Nasal cannula (0.25-3 L/min) for consistent oxygenation 2
   • For moderate-severe bronchiolitis: HFNC 1
   • For specific short-term needs requiring high FiO2: Consider oxygen hood 3
   • Target SpO2 90-97% for infants with bronchiolitis 1

3. For adults:

   • Medium-concentration needs: Nasal cannula (2-6 L/min) 2
   • Need for precise FiO2 control: Venturi mask 2
   • High-concentration needs: Reservoir mask at 15 L/min 2
   • Target SpO2 94-98% for most patients; 88-92% for those at risk of hypercapnia 2

4. Consider patient comfort and compliance:

   • Nasal cannulae are generally better tolerated than masks 2
   • Alternative "blow-by" methods may be considered for children who reject face masks 5

Common Pitfalls and Caveats

• Oxygen hoods require flow rates of at least 4 L/min in small hoods and 3 L/min in medium/large hoods to prevent carbon dioxide retention 4.
• The actual oxygen concentration delivered by an oxygen hood varies based on hood size, lid position, and patient size/movement 4.
• Automated oxygen delivery systems may increase time in desired SpO2 ranges compared to manual adjustments, but evidence for clinical outcome benefits is limited 6.
• For patients with COPD or those at risk of hypercapnic respiratory failure, avoid high-concentration oxygen and target SpO2 88-92% 2.
• Oxygen saturation should be monitored during different activities (sleep, feeding, awake) before weaning supplemental oxygen 2.