On CPAP, central apneas appear at 15 cwp. What is the most likely cause?

On CPAP, central apneas appear at 15 cwp. What is the most likely cause?

• A. The CPAP pressure is too low
• B. The CPAP pressure is too high
• C. There is a mask leak
• D. This is natural and isnt a concern

Answer: (B)

When central apneas appear only at high CPAP pressures, the likely cause is that the pressure is too high. Elevating airway pressure can suppress the brain’s drive to breathe by lowering arterial CO2 below the level needed to stimulate ventilation, leading to brief pauses in respiratory effort known as central apneas. This phenomenon is often called therapy-emergent central sleep apnea, where the treatment itself destabilizes breathing at higher pressures. If the pressure were too low, you'd expect ongoing obstructive events rather than central pauses. A mask leak tends to cause poor delivery or movement artifacts rather than true central apneas. Calling it natural wouldn’t fit the pattern of central events triggered specifically by a relatively high pressure. Therefore, reducing the CPAP pressure is the most appropriate step.

When central apneas appear only at high CPAP pressures, the likely cause is that the pressure is too high. Elevating airway pressure can suppress the brain’s drive to breathe by lowering arterial CO2 below the level needed to stimulate ventilation, leading to brief pauses in respiratory effort known as central apneas. This phenomenon is often called therapy-emergent central sleep apnea, where the treatment itself destabilizes breathing at higher pressures.

If the pressure were too low, you'd expect ongoing obstructive events rather than central pauses. A mask leak tends to cause poor delivery or movement artifacts rather than true central apneas. Calling it natural wouldn’t fit the pattern of central events triggered specifically by a relatively high pressure. Therefore, reducing the CPAP pressure is the most appropriate step.