CPAP stands for Continuous Positive Airway Pressure. It delivers a single, fixed pressure all night long. While effective, some users find it uncomfortable—especially if their pressure needs vary during sleep.
APAP, or Automatic Positive Airway Pressure, adjusts the pressure automatically based on your breathing patterns. It increases or decreases airflow as needed, offering more comfort and flexibility. This makes APAP ideal for most people with obstructive sleep apnea, especially those whose needs change due to sleep position, congestion, or other factors.
BiPAP, or Bilevel Positive Airway Pressure, is a bit different. It provides two distinct pressure levels—one for inhaling and a lower one for exhaling. BiPAP is typically prescribed for people with more complex sleep disorders, like central sleep apnea or COPD, or those who need higher pressures and find CPAP or APAP difficult to tolerate.
In short:
CPAP = fixed pressure
APAP = auto-adjusting pressure
BiPAP = two pressures (inhale/exhale), for more complex needs