What adjustments should be made to oxygen therapy and BiPAP settings with an FiO2 of 60%?

Adjusting Oxygen Therapy and BiPAP Settings with an FiO2 of 60%

With an FiO2 of 60%, immediate assessment of oxygenation status is required with consideration for either reducing oxygen concentration if SpO2 is above target range or escalating respiratory support if oxygenation remains inadequate.

Assessment of Current Oxygenation Status

When managing a patient on BiPAP with an FiO2 of 60%, the first step is to assess the patient's current oxygenation status:

• Check SpO2 and arterial blood gas values
• Evaluate respiratory rate, work of breathing, and patient comfort
• Review underlying condition and reason for respiratory support

Target Oxygen Saturation Guidelines

Different target SpO2 ranges should be maintained based on the patient's condition:

• For most patients: 94-98% 1
• For patients with COPD or risk of hypercapnic respiratory failure: 88-92% 1
• For patients with evidence of acute or chronic type 2 respiratory failure: 88-92% 2
• For pregnant patients: >94% 2

Decision Algorithm for FiO2 Adjustment

If SpO2 is Above Target Range:

• Reduce FiO2 gradually in 5-10% increments
• Wait 5-10 minutes between adjustments to assess response
• Continue reducing until SpO2 is within target range
• Goal: Use the lowest FiO2 possible while maintaining target SpO2

If SpO2 is Below Target Range:

• Increase BiPAP pressure settings first before further increasing FiO2
• Consider increasing CPAP/EPAP to 12-15 cmH2O 2
• If inadequate response, consider escalation to higher level of care

BiPAP Pressure Adjustments

When FiO2 is at 60%, pressure adjustments should be considered:

1. Inspiratory Positive Airway Pressure (IPAP):

   • Increase if tidal volume is low (<6-8 mL/kg) 2
   • Increase if PCO2 remains elevated (>10 mmHg above goal) for >10 minutes 2
   • Increase if SpO2 remains <90% for >5 minutes despite adequate FiO2 2
   • Typical range: 17-35 cmH2O 1

2. Expiratory Positive Airway Pressure (EPAP):

   • Current guidelines recommend CPAP/EPAP of 10-12 cmH2O for hypoxemic respiratory failure 2
   • Can be increased to 12-15 cmH2O if further escalation needed 2
   • Typical starting value: 7 cmH2O 1

3. Backup Rate/Respiratory Rate:

   • Use ST mode (spontaneous/timed) for patients with central hypoventilation, central apneas, or muscle weakness 2
   • Set backup rate equal to or slightly less than spontaneous sleeping respiratory rate (minimum 10 bpm) 2
   • Increase in 1-2 bpm increments every 10 minutes if goals not met 2

Monitoring Requirements

With an FiO2 of 60%, close monitoring is essential:

• Monitor patient's condition within 1-2 hours after initiating or adjusting BiPAP 2
• Perform arterial blood gas analysis 30-60 minutes after starting oxygen therapy 1
• Continuously monitor SpO2, respiratory rate, and heart rate 1
• Watch for signs of deterioration requiring escalation of care

Special Considerations

For Type 1 (Hypoxemic) Respiratory Failure:

• CPAP is indicated as first-line therapy 2
• Initial settings: CPAP 10 cmH2O with FiO2 0.6 2
• If further escalation needed: increase CPAP to 12-15 cmH2O with FiO2 0.6-1.0 2

For Type 2 (Hypercapnic) Respiratory Failure:

• BiPAP is preferred over CPAP 2
• Consider BiPAP for patients with COPD or other conditions with CO2 retention 2
• Target SpO2 88-92% to avoid worsening hypercapnia 1

Common Pitfalls to Avoid

1. Excessive oxygen: Providing too high FiO2 in COPD patients can worsen hypercapnia
2. Delayed escalation: Failing to recognize when BiPAP is insufficient and intubation is needed
3. Mask leaks: Ensure proper mask fit to maintain effective pressure delivery
4. Patient discomfort: Adjust settings for comfort to improve tolerance and compliance
5. Overlooking underlying cause: Continue treating the primary condition causing respiratory failure

When to Consider Escalation

Consider escalation to invasive mechanical ventilation if:

• Persistent hypoxemia despite BiPAP optimization and FiO2 60%
• Worsening respiratory acidosis
• Decreased level of consciousness
• Inability to protect airway
• Hemodynamic instability

Remember that NIV failure rate is approximately 45% in some studies, even with optimal settings 2, so be prepared to escalate care promptly if needed.