CPAP treatment for sleep apnea maintains airway patency by delivering continuous positive pressure during which phase?

• A. During sleep, by delivering continuous positive airway pressure to keep the airway open.
• B. Only during exercise.
• C. Only when awake.
• D. To lower blood pressure throughout the day.

Answer: (A)

CPAP works by delivering continuous positive airway pressure to act as a splint for the upper airway, preventing collapse when you’re asleep. The airway tends to become obstructed during sleep because muscle tone decreases, especially in certain sleep stages. By providing a constant pressure, CPAP keeps the airway open and airflow uninterrupted during that vulnerable phase. It isn’t focused on exercise or wakefulness, where airway collapse isn’t the same issue, and while treating sleep apnea can improve daytime symptoms and may influence blood pressure, the described mechanism centers on keeping the airway patent during sleep.