CPAP* and BiPAP devices are commonly used in the treatment of sleep apnea.¹

Both devices use air pressure generated by a machine to send air through a tube to a face mask, but that is where the similarities end in terms of the way the treatment is delivered.  

In this article, we look at how CPAP and BiPAP therapies work, the differences between the two treatment options and whether BiPAP, a more specialized form of therapy, could be a suitable choice for you.

Remember to check with a healthcare professional for advice on what device will best meet your therapy needs.

CPAP - single fixed pressure setting

CPAP (continuous positive airway pressure) is primarily used to treat OSA.² It delivers a continuous flow of air at a fixed pressure to therapy users. That setting is prescribed by a healthcare professional after you have undergone an overnight sleep study or home sleep test.¹

Advantages

CPAP therapy is among the most effective and widely prescribed treatments for OSA, and it is often the first choice for people newly diagnosed with OSA. Continued and consistent use of a CPAP machine can help alleviate the symptoms of OSA.¹
 

Disadvantages

CPAP devices don't work for everyone. Some people may find it difficult adapting to the continuous airflow. Therapy users can also feel uncomfortable when wearing an ill-fitting mask that is causing skin irritation and excessive mask leak.
 

BiPAP – two-level pressure setting

While CPAP delivers one pressure, BiPAP (bi-level positive airway pressure) delivers two. This means your doctor has prescribed a different pressure for inhaling (inspiratory positive airway pressure or IPAP) than has been set for exhaling (expiratory positive airway pressure or EPAP). Therefore, the pressure range for therapy delivery can be customized to the user.² BiPAP is generally used by people experiencing more serious health conditions, such as chronic obstructive pulmonary disease (COPD).

Advantages of BiPAP
BiPAP could be a suitable treatment for people who are not getting enough oxygen or who have trouble expelling sufficient CO₂. The device can also deliver air pressure higher than the recommended average setting to people who need a higher pressure than they can receive from CPAP.

Disadvantages of BiPAP
BiPAP is costly and can be priced two to three times higher than CPAP. Accordingly, some insurance companies may need further evidence you need BiPAP to treat your condition before they provide you with cover. Some BiPAP therapy users say the higher air pressure settings can take time to adjust to.

What are the major differences between CPAP and BiPAP?

The core difference, as outlined above, is that CPAP uses a continuous pressure while BiPAP changes the pressure between inhaling and exhaling. The two-level pressure setting may make BiPAP a more effective treatment option for people with chronic health conditions.¹

So, which is better for me - CPAP or BiPAP?

Only a medical professional can provide you with this advice and that decision is most likely to be made after you have undergone a sleep study. If CPAP is not giving you satisfactory results, you may be a candidate for BiPAP, but check with your doctor before you make the switch.

Who should consider BiPAP therapy?

According to a John Hopkins University School of Medicine article on BiPAP, people with a medical problem that impairs breathing, such as obesity hypoventilation syndrome, could be good candidates for BiPAP.³ Others who may also consider BiPAP include those who:

• need more assistance than CPAP provides
• are experiencing asthma problems
• are having trouble breathing after an operation
• have exceptionally low blood oxygen levels
• have too much carbon dioxide in their bloodstream.

See also, What is the difference between CPAP and APAP?