Both Cpap and Bipap machines are used to manage chronic sleep apnea by preventing obstructive sleep apnea episodes, but Bipap machines are also used to manage central sleep apnea – which is caused by interrupted signals from the brain stem.
The main difference between the two devices is that while Cpaps have one pressure setting, Bipaps have two pressure settings. This creates crucial differences in how they work – making one more suitable than the other for certain sleep apnea sufferers, and sufferers of other breathing-related problems, or diseases that can disrupt breathing.
Cpap machines deliver a flow of air at a single, constant, pressure: This constant pressure is effective in keeping the upper airway open during sleep, preventing relaxed throat muscles closing and narrowing or cutting off the person’s airway. This is ideal for most obstructive sleep apnea sufferers, but not all. Some people find that the air pressure from Cpap machines can feel too high while they are awake, making them feel like it is preventing them from breathing out properly. This can be very distressing.
Bipap machines deliver IPAP (Inspiratory Positive Airway Pressure) at a high level, and EPAP (Expiratory Positive Airway Pressure) at a lower pressure: This is better for people who struggle with breathing out, people with severe obstructive sleep apnea, the less common ‘central’ sleep apnea, and some other conditions that can disrupt breathing in a sleep-state – as congenital heart disease, neuromuscular diseases, and some lung diseases. Bipaps can force an extra breath in these cases.
After you have had a sleep study done your doctor will advise on which device is better for you and will set the air pressures according to your needs. They will also advise on whether you need a Bipap machine that can ‘ramp’ pressure from a lower setting to a higher one after a period of time.