BiPAP vs CPAP vs APAP vs VPAP: The Differences

Thousands of adults and even some children are afflicted with sleep apnea. Treatment therapy is generally through Continuous Positive Airway Pressure (CPAP) machine. There are currently four different devices available for use by patients with any of the three forms of apnea, but the main two devices used most often in treatment with patients are the CPAP and the BiPAP. After the initial sleep study to diagnose the condition, your doctor or clinician recommends one of these therapy devices for you to use for your treatment therapy. It is important to understand the differences and similarities as well as benefits and drawbacks of each of these when you consider whether to use the BiPap vs CPAP machine.

Recommended CPAP Machines:

Recommended CPAP Masks:

The pressure released in controlled bursts from a CPAP machine is at one constant level designed to increase air pressure in the throat so the airway does not collapse during inhalations while sleeping. The air pressure is delivered at a single predetermined pressure level. Some patients have a difficult time adjusting to wearing the mask and accepting the air pressure as they fall asleep until they become accustomed to it. They find it irritating to their eyes and face. A properly fitted mask is key. Using the device each night produces the best results but some patients do not use it daily or even stop using it altogether because they do not adjust to wearing a mask. Rather than do that, you should ask to try a new type of mask instead.

In contrast to the CPAP, the Bi-level Positive Airway Pressure (BiPAP) system has two different levels of pressure for the airway. Inspiratory positive airway pressure (IPAP) is a high level of pressure applied through the machine as the patient inhales. Expiratory positive airway pressure (EPAP) is a lower level of pressure applied when the patient exhales. The air pressure measurements are determined during a professional sleep study and are set by a technician. BiPAP uses must be monitored periodically for any needed changes in their pressure settings. BiPAP machines are recommended to treat severe OSA and central sleep apnea. They are also prescribed for heart patients and other respiratory diseases.

Some of the differences between the CPAP and the BiPAP are that the CPAP pressure setting is fixed while the BiPAP’s can be adjusted. The CPAP delivers one level of air pressure while the BiPAP delivers two. A CPAP is less expensive than a BiPAP, while the BiPAP tends to be slightly noisier than the CPAP. CPAP settings do not require monitoring and the BiPAP settings need to be monitored occasionally by a clinician. Both benefit from the inclusion of a heated humidifier filled with distilled water to prevent the nasal congestion that is frequently a side effect of breathing the dry air of the machines. People who use CPAPs and have problems getting accustomed to them are sometimes switched to BiPAPs to see if they can tolerate these better.

Recommended BiPAP Machines:


CPAPS and BiPAPS are used by the majority of sleep apnea patients for their treatment therapy but there are other air flow systems now available. These are the Automatically-adjusting Positive Airway Pressure (APAP) machine and the Variable Positive Airway Pressure (VPAP) machine. The most recent APAP devices can automatically minute by minute adjust the pressure needed to keep the user’s airway open. The APAP can adjust the pressure as needed when changes occur in sleep positions or stages, such as REM sleep, during the night. Clinical trials indicate that these devices can actually prevent apneas and hypopneas before they occur. These devices operate on mathematical algorithms, different and patented for each company. Check to make sure that the brand you are considering has been clinically validated by third party testing.

The Variable or VPAP device is similar but goes a step further to manage the patient on a breath to breath basis. The VPAP was developed specifically to treat central sleep apnea in all its variations. It normalizes breathing by suppressing CSA and/or Cheyne-Stokes respiration (CSR). It improves the amount of time the patient spends in REM sleep. It automatically uses its algorithm to calculate target ventilation and adjusts the air pressure level to support achieving it. For example, it considers the patient’s recent average ventilations and sets a goal of 90 percent of the recent averages. Central apnea is the result of the body’s lack of respirations, so this is an interesting break-through.

It is good to be knowledgeable about choices and to know when to use BiPAP vs CPAP vs APAP vs VPAP devices. Whether patients select the BiPAP vs CPAP, or branch out and try the newer and more expensive APAP or VPAP, it is good to know there are choices available to those who need help with their breathing when they sleep at night. A good night’s sleep is vital to a body’s overall health.


Obstructive Sleep Apnea Positional Therapy and Devices