What are the maximum Inspiratory Positive Airway Pressure (IPAP) and Expiratory Positive Airway Pressure (EPAP) settings for a patient requiring bilevel positive airway pressure (BiPAP) therapy?

Maximum IPAP and EPAP Settings for BiPAP Therapy

The maximum IPAP is 30 cm H₂O for patients ≥12 years and 20 cm H₂O for patients <12 years, while EPAP has no absolute maximum but is typically limited by the need to maintain an IPAP-EPAP differential of 4-10 cm H₂O. 1, 2

Age-Stratified Maximum IPAP Settings

• For adults and adolescents ≥12 years: Maximum IPAP is 30 cm H₂O 1, 2
• For children <12 years: Maximum IPAP is 20 cm H₂O 1, 2

These limits represent consensus recommendations from the American Academy of Sleep Medicine and apply across both obstructive sleep apnea titration and chronic alveolar hypoventilation syndromes. 1

EPAP Considerations

EPAP has no specified absolute maximum in the guidelines, but practical limits exist based on:

• Minimum starting EPAP: 4 cm H₂O for both pediatric and adult patients 1, 2
• IPAP-EPAP differential constraints: The pressure support (difference between IPAP and EPAP) should range from a minimum of 4 cm H₂O to a maximum of 20 cm H₂O 1, 2
• For obstructive sleep apnea specifically: The IPAP-EPAP differential is recommended to be 4-10 cm H₂O 1, 2

This means if you reach maximum IPAP of 30 cm H₂O and need to maintain at least 4 cm H₂O pressure support, the practical maximum EPAP would be 26 cm H₂O. However, for OSA titration with the recommended 4-10 cm H₂O differential, EPAP would typically not exceed 20-26 cm H₂O. 1, 2

Pressure Support (PS) Limits

• Minimum PS: 4 cm H₂O 1, 2
• Maximum PS: 20 cm H₂O 1, 2

The pressure support is calculated as IPAP minus EPAP, so these limits constrain the relationship between the two pressures. 1

Titration Algorithm

When approaching maximum pressures, follow this sequence:

1. Start conservatively: Begin with IPAP 8 cm H₂O and EPAP 4 cm H₂O 1, 2

2. Increase gradually: Raise IPAP and/or EPAP by at least 1 cm H₂O increments with minimum 5-minute intervals between adjustments 1, 2

3. For obstructive events: Increase both IPAP and EPAP (or EPAP alone depending on event type) until apneas, hypopneas, RERAs, and snoring are eliminated 1

4. For hypoventilation: Increase pressure support (IPAP while maintaining EPAP at minimum needed for airway patency) every 5 minutes if tidal volume remains <6-8 mL/kg or PCO₂ remains ≥10 mmHg above goal 1, 2

5. If maximum IPAP reached without adequate control: Consider switching to spontaneous-timed mode with backup rate or alternative ventilation strategies 1, 2

Critical Caveats

Patient tolerance supersedes guideline maximums. If a patient awakens complaining of excessive pressure, decrease to a lower comfortable level that allows return to sleep, even if this means accepting suboptimal respiratory event control temporarily. 1

Higher starting pressures may be appropriate for patients with elevated BMI or during retitration studies, though specific methodology lacks strong evidence. 1, 2

For chronic alveolar hypoventilation patients, the same 30 cm H₂O maximum IPAP applies, but you may need the full 20 cm H₂O pressure support range to achieve adequate tidal volumes of 6-8 mL/kg. 1, 2

Avoid the common error of increasing EPAP to manage hypercapnia—EPAP maintains airway patency but does not significantly increase minute ventilation. Only increasing IPAP (thus increasing pressure support) improves ventilation in hypercapnic patients. 2