How to manage Continuous Positive Airway Pressure (CPAP) therapy?

Managing Continuous Positive Airway Pressure (CPAP) Therapy

CPAP therapy should be initiated at 4 cm H2O for both pediatric and adult patients, with a maximum pressure of 15 cm H2O for patients <12 years and 20 cm H2O for patients ≥12 years, and patients should be encouraged to use CPAP whenever they sleep to maximize health benefits and reduce mortality risk. 1, 2

Initial CPAP Titration

Starting Parameters

• Begin with a minimum pressure of 4 cm H2O for all patients 1
• Maximum pressure limits:
  • Patients <12 years: 15 cm H2O
  • Patients ≥12 years: 20 cm H2O 1

Titration Algorithm

1. Increase CPAP pressure when:

   • ≥1 obstructive apnea observed in patients <12 years
   • ≥2 obstructive apneas observed in patients ≥12 years
   • ≥1 hypopnea observed
   • ≥1 minute of loud/unambiguous snoring in patients <12 years
   • ≥3 minutes of loud/unambiguous snoring in patients ≥12 years 1

2. Pressure adjustment increments:

   • Standard titration: 1-2.5 cm H2O increases
   • Split-night studies: May use larger increments (2-2.5 cm H2O) due to shorter titration time 1

3. "Exploration" of pressure:

   • After control of respiratory events is achieved, pressure may be increased by up to 5 cm H2O to normalize airway resistance
   • This can reduce residual high airway resistance that may cause repetitive arousals and insomnia 1

4. If patient complains of high pressure:

   • Reduce to a comfortable level that allows return to sleep
   • Resume titration from this lower pressure 1

Monitoring CPAP Adherence

Key Metrics to Track

• Date ranges of device usage
• Total nights CPAP was used/not used
• Percentage of nights with CPAP usage
• Percentage of nights with CPAP usage >4 hours
• Average usage on nights when CPAP was used
• Average usage on all nights 1

Adherence Targets

• Primary goal: Use CPAP whenever sleeping (day or night) 1, 2
• Minimum adherence threshold:

  • 4 hours/night on 70% of nights during a consecutive 30-day period (CMS requirement) 1

  • OR >2 hours/night with demonstrable improvement in symptoms 1

Early Intervention

• Assess adherence early (within 7-90 days of initiation) rather than waiting for the standard 31-90 day window 1, 2
• Early identification and resolution of issues improves long-term adherence 1, 2
• Poor mask fit is a common cause of non-adherence and should be addressed promptly 2, 3

Optimizing CPAP Effectiveness

Mask Selection and Leak Management

• Monitor mask leak measurements:
  • Different manufacturers have different thresholds for what constitutes excessive leak
  • ResMed: <24 L/min with nasal interface, <36 L/min with full face interface
  • Fisher & Paykel: <60 L/min
  • DeVilbiss: <95 L/min 1
• Proper mask selection is critical for treatment success and adherence 3

Humidification and Education

• Implement heated humidification to improve comfort and adherence 4
• Provide systematic educational programs to improve utilization 4, 2

Addressing Side Effects

• Patients who experience side effects use CPAP significantly less 5
• Common side effects include nasal congestion, skin irritation, and mask discomfort
• Promptly address these issues to improve adherence 5

Alternative Approaches

For CPAP Intolerance

• Consider auto-CPAP devices which have similar efficacy to fixed CPAP 2
• Bilevel positive airway pressure (BPAP) may be an option for patients unable to tolerate conventional CPAP 6, 4
• For mild to moderate OSA (AHI <30/h), mandibular advancement devices may be considered 2

Follow-up Schedule

Initial Follow-up

• Schedule within the first few weeks to establish utilization patterns 4
• Download compliance data to objectively assess usage 2
• Address any mask, machine, or usage problems 4

Long-term Follow-up

• Recommended yearly or as needed 4
• Monitor for improvement in:
  • Daytime sleepiness (Epworth Sleepiness Scale)
  • Blood pressure
  • Cardiovascular outcomes
  • Cognitive functioning
  • Quality of life 2

Common Pitfalls to Avoid

• Waiting too long to address adherence issues: Early intervention (within first week) is more effective than waiting 30+ days 2
• Focusing only on hours of use: Even partial use (>2 hours/night) can provide clinical benefits 1
• Overlooking mask fit issues: Poor mask fit is a major cause of non-adherence 3
• Ignoring weight management: Weight loss should be recommended for all obese patients with OSA 2
• Missing comorbid conditions: Consider potential Obesity Hypoventilation Syndrome in patients with high BMI 2