CPAP vs APAP vs BiPAP: Which Do You Need?

CPAP, APAP and bilevel devices deliver positive airway pressure in different ways. The prescribed therapy type and exact mode—not price or appearance—should guide your purchase.

The main differences

Fixed CPAP delivers the pressure prescribed by the clinician.
Auto CPAP (APAP) adjusts pressure within prescribed limits in response to the breathing pattern.
Bilevel devices provide separate inspiratory and expiratory pressures. Spontaneous, auto-bilevel and spontaneous/timed modes have different functions and are not interchangeable.

Match the full model to the prescription

Examples in the range include AirSense AutoSet and prisma SMART for auto CPAP, AirCurve VAuto for auto-bilevel, and specified ST models for prescribed timed-backup support. Available modes differ by model, including within the Lumis family; do not assume every model includes iVAPS or another specialist mode.

There is no single pressure threshold that lets a shopper decide to switch from CPAP to bilevel. Suitability depends on clinical assessment, diagnosis and treatment requirements.

Before ordering

Confirm the exact device and therapy mode with your clinician.
Review the mask, humidifier, tubing and filters included in the selected package.
Check regional connectivity, current price, availability and support arrangements.
Ask how prescribed settings will be reviewed and arranged; do not copy settings from another person’s device.

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Clinical guidance: This guide is general information. Device choice and therapy settings must follow your treating clinician’s advice.