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BiPAP Vs. CPAP Vs. APAP: Which PAP Machine Is The Best For You?

Airway obstruction while sleeping has become a frequent modern-day occurrence and health condition. There seems to be a growth in cases of obstructive sleep apnea, and conditions where the airway becomes obstructed and causes interrupted breathing. Such cases can account for the development of further, and sometimes even more severe conditions, so appropriate treatment and care is often necessary.

PAP or positive airway pressure machines have come to be the best treatment option for cases of sleep apnea and obstructive, congested breathing. Even nowadays, when COVID-19 is known to affect the respiratory system terribly, PAP machines are being used alongside ventilators to help treat breathing and lung problems.

But, because there can be various breathing difficulties and respiratory conditions, the same PAP machine cannot be applied equally for every case. That is why the PAP industry has expanded in the last few decades and come up with different types of PAP machines; BiPAP, CPAP, and APAP. In the following paragraphs, we’re going to take a look at each type and see its characteristics and predicted application. So let’s get started!

BiPAP Vs. CPAP Vs. APAP: Quick Overview

BiPAP Machines – deliver different pressures on inhaling and exhaling

CPAP Machines – provide therapy at only one, continuous pressure

APAP – automatically adjust therapy pressure based on the patient’s breathing and need.

BiPAP (Bi-level Positive Airway Pressure)


Terry Cralle, RN

What is BiPAP?

BiPAP stands for Bi-level Positive Airway Pressure and is used as a non-invasive therapy for patients suffering from sleep apnea. A BiPAP machine delivers pressurized air to a patient through a face, nasal mask, and acts as ventilator support.

The machine is a relatively small device and can be used in hospitals or at home (only with a proper diagnosis and prescription).

A BiPAP machine operates in a programmed manner, where it offers two types of airflow pressure;

  • IPAP – Inspiratory Positive Airway Pressure or positive pressure on inspiration,
  • EPAP – Expiratory Positive Airway Pressure or positive pressure on expiration

With these two types of airflow pressure, a BiPAP machine enables the patient to push air and oxygen into the lungs. It further helps patients maintain airway patency, which allows oxygen to diffuse and provide pulmonary circulation.

The machine can operate as spontaneous or timed assistance, meaning it can deliver air/breaths when triggered by the patient or only in the way that it was set (set respiratory rate). Either way, it provides and maintains a set, prescribed exhalation pressure.

When Is BiPAP Machine Used?

BiPAP machine is generally used in cases of sleep apnea where the breath timing is essential. This means that the patient requires one of the two BiPAP airflow pressure modes or requires a spontaneous or timed respiratory rate.

The dual setting of the machine makes it perfect for natural airflow and breathing that doesn’t interrupt sleep. BiPAP can be used in other therapy cases like;

  • Conditions with lung or neuromuscular disorders
  • Conditions with cardiopulmonary disorders (e.g. congestive heart failure)
  • Conditions with muscle weakness (inadequate respirations)
  • Conditions with poor lung compliance (poor lung expansion)
  • In cases of pulmonary congestion
  • In cases where other PAP machines have failed to provide adequate treatment.

It is important to mention that the BiPAP machine isn’t always the primary treatment choice.

BiPAP machines are often applied when other PAP machines have failed in their treatment and patients are looking for an alternative.

Sometimes other PAP machines have pressure settings that patients find too difficult to handle, so a safe and less invasive alternative is a BiPAP machine.

So, a doctor will prescribe a BiPAP machine to you after the results of previous treatments (like CPAP treatment for example). Your doctor or medical professional should know right away if a BiPAP machine will be useful to you, especially when it comes to pressure settings.

Prescription is the only way to get a hold of a BiPAP machine (since the doctor needs to prescribe inhalation or exhalation pressure and other necessary respiratory settings).

Benefits Of BiPAP Therapy

There are several benefits to BiPAP therapy and treatment;

  • A BiPAP machine can decrease the pressure against which a patient exhales; this ensures easier breathing and decrease in abdominal muscle recruitment, which is useful in cases of weak muscles, poor lung expansion, etc.
  • A BiPAP machine is made to fight against the inspiration flow limitation, often caused by collapsed tongue and narrow upper airway.
  • BiPAP therapy has shown to relieve respiratory muscles and balance or administer the pressure between the inspiratory and expiratory cycles.
  • A BiPAP machine offers dual mode airflow pressure which has shown to provide more comfortable inhalation and exhalation cycles. The dual-mode is further adjustable to each patient for more comfort and better pressurization rate when it comes to IPAP and EPAP.

Possible Disadvantages To BiPAP Therapy

There can always be some complications with PAP therapies. Here are some possible disadvantages and complications to BiPAP therapy;

  • Skin rash and breakdown – because BiPAP, like other PAP machines, uses a mask, there can be cases of skin rash and breakdown. To avoid this, the mask needs to fit tightly (but not too tightly), and the skin needs to be treated with appropriate creams and moisturizers.
  • Sinus congestion – sometimes the nasal mask can cause humidification to the machine. It can even increase the temperature of the humidity, so it is important to adjust mask tightness and consult a medical professional about the sinus congestion caused by this (as well as the possible treatment).
  • Eye irritation – if the mask isn’t placed properly, it can leak the air and pressure causing eye redness, dryness, and irritation.
  • Other possible complications – nasal drying, general discomfort regarding ventilation, aspiration, discomfort caused by the tube, etc.

CPAP (Continuous Positive Air Pressure)

CPAP (Continuous Positive Air Pressure)

Terry Cralle, RN

What Is CPAP?

CPAP stands for Continuous Positive Air Pressure and is used as a treatment for conditions like obstructive sleep apnea. CPAP machines are designed to help open the airway (and maintain it as such) and deliver continuous airflow through the open airway.

Just like the BiPAP machine, the CPAP machine provides pressurized air through a mask and acts as ventilator support; only the CPAP machine provides continuous assistance, throughout the night.

Because obstructive sleep apnea is characterized by reduction and even complete halt of breathing caused by the narrowing of the upper airway, the CPAP machine ensures that during sleep the patient continues breathing even when the airway is at its narrowest.

CPAP machine operates by providing continuous supply of air at the same pressure to the patient with each breath. CPAP does this through the nasal mask, but the mask doesn’t breathe for the patient.

The airflow simply creates enough pressure to keep the airways open, but sometimes the machine can improve the way a person breathes on their own. In some cases, the CPAP machine delivers air to the patient through a tube that is placed into the nose.

This way, it provides gentler pressure to the airway and is less invasive.

When is CPAP Machine Used?

Just like the BiPAP machine, the CPAP machine is also generally used for the case of OSA, or obstructive sleep apnea.

However, unlike BiPAP, CPAP is used in cases where the patient needs continuous breathing assistance, throughout the night.

The air supply with CPAP is continuous and operates at only one pressure level.

CPAP machines can come with pressure relief settings because continue pressure delivery can be rather invasive for some OSA patients. Nevertheless, CPAP is considered the primary, and often even the best treatment for sleep apnea.

However, CPAP machines can be used in various other therapy cases, like;

  • Conditions with respiratory distress syndrome (usually in infants)
  • Conditions with cardiopulmonary disorders (e.g. congestive heart failure)
  • In the case of upper airway resistance syndrome (UARS)
  • In the case of snoring
  • In the case of pulmonary disease
  • In case of respiratory support for Covid-19 patients (as non-invasive ventilation) but this use has specialists and experts divided (there have been cases where non-invasive ventilation increased the risk of infectious transmission).

CPAP machines are FDA regulated medical devices and they are only available through proper prescriptions. Moreover, to buy a CPAP device, you will need to contact an official seller or retailer, since it is considered illegal to sell CPAP machines privately. Buying a device with a prescription protects you as a patient because you’re buying a device with proper therapy pressure that fits your diagnosis and needs.

Also Read:

Best CPAP Machines 2021: 5 Out of 8

12 CPAP Side Effects You Should Know (Only 5 are Common)

Tip: You can also do an in-home sleep test to have sleep apnoea confirmed, if you’re in the US, you can get help from cpapmyway, if you’re in the UK, we recommend a sleep test

Benefits of CPAP Therapy

There are several benefits to CPAP therapy and treatment;

  • CPAP machines can improve a patient’s sleep quality and sleep onset, as well as diminish waking up throughout the night due to a lack of breathing interruptions. Moreover, daytime sleepiness is also diminished with patients using CPAP therapy.
  • CPAP machine reduces snoring in OSA patients. Because snoring is caused by a collapsed upper airway and tongue, a CPAP machine expands the airway and prevents the muscles to narrow and the tongue to collapse to its base, all of which contribute to snoring.
  • CPAP therapy has also shown positive, therapeutic effects on neurocognitive function, mood, and quality of life. In fact, studies have shown that patients on CPAP have better concentration, work efficiency, sex drive, can drive better and longer, are generally happier, and have better health overall.
  • CPAP therapy has also shown to diminish cardiovascular disease risk in OSA patients, and lowers the possibility of inflammation development. Also, in cases of ischemic stroke, CPAP therapy has proven to reduce the risk of mortality and ensure a longer and higher survival rate.

Possible Disadvantages To CPAP Therapy

Here are some possible and common complications that can occur during CPAP therapy;

  • Skin marks and rashes – if the CPAP mask doesn’t fit properly, it is very likely to cause skin marks, rash, and overall skin irritation. This applies especially for people with sensitive skin where a loosely-fitting mask can cause sores and even ulcers. It is essential the mask fits properly and that the skin is treated with moisturizers or over-the-counter medical cream/gel that can relieve symptoms.
  • Nose, mouth, and throat dryness – one of the most common complaints regarding the CPAP therapy is the dryness of the nose, mouth, and throat, usually caused by leakage (air escaping the mask). This can lead to nosebleed, parched mouth, and tongue, throat infections, etc. Therefore, it is important to opt for CPAP machines that provide humidifying options or heated tubing that prevent you from drying out. Also, it is essential to have a properly fitting mask that covers both, your mouth and nose.
  • Air swallowing or aerophagia – this is a common thing experienced during CPAP therapy. This usually happens because the CPAP pressure is too high, and results in excessive air in your stomach. Symptoms of air swallowing include bloating, burping, and excessive gas.
  • Other possible complications may include the feeling of claustrophobia, development of central sleep apnea, problems with exhalation, nasal congestion, etc.

APAP (Automatic Positive Airway Pressure)


Terry Cralle, RN

What Is APAP?

APAP stands for Automatic Positive Airway Pressure and is used to treat medical conditions like obstructive sleep apnea. APAP machine is a special type of CPAP machine, however, there is one major difference.

APAP device is designed to deliver air at varying pressures, in accordance with your breathing, instead of just blowing one consistent pressure (like CPAP devices do). As the patient’s breathing pattern changes throughout the night, so does the pressure from the APAP device.

So, what the device does is use a quiet motor to pressurize the air that you breathe, opens your airway, and allows the air to reach your lungs. The APAP machine is able to make automatic adjustments by constantly measuring the resistance present in your breathing, so it knows whether to decrease or increase the pressure to stabilize the airway.

Other than the different pressure delivery, APAP devices are, in fact, similar to CPAP devices. There may be some other differences, like in the type of masks or tubes (which are often more comfortable in APAP machines), but the purpose and use are the same.

When Is APAP Machine Used?

Just as the previous two PAP devices, APAP machines are generally used in the treatment of obstructive sleep apnea. Even though CPAP machines continue to be the forerunner for OSA treatment, APAP machines are often favorized because of the less invasive and more natural approach to treatment.

Often, patients diagnosed with less serious sleep apnea would be firstly prescribed with APAP for initial treatment.

In case the APAP device doesn’t do the job, then the CPAP machine needs to step in.

Other than sleep apnea, APAP devices have shown to be effective in some other cases, like;

  • Conditions where breathing is interrupted, like nasal congestion, sinus issues, airway infections, etc.
  • Conditions where cardiac health is at risk
  • Conditions where blood pressure is disrupted
  • In the case of snoring
  • In the case of fatigue, daytime tiredness, and general weakness
  • In the case of sleeplessness or inability to fall asleep.

Just like the other PAP devices, the APAP machine is only available through prescription. However, in some cases, if you’re prescribed with a CPAP device you can choose between CPAP and APAP machines. However, this doesn’t apply to other PAP devices.

Benefits Of APAP Therapy

There are several benefits to APAP therapy and treatment;

  • APAP machines allow auto-adjusting pressure settings, so in certain APAP models, the auto-adjusting setting can even turn your APAP device into a CPAP device. This can save you money and time looking for a new CPAP device.
  • Because people have different breathing needs, the APAP machine allows you to increase or decrease the pressure and adjust settings as you like. However, if you aren’t aware of your breathing needs (since you’re not aware of how you breathe in sleep), the machine can change adjustments on its own as it recognizes your breathing pattern and change in the pattern.
  • APAP machines are designed to detect even the slightest, most subtle changes in your breathing, regardless of your sleeping position. So, the air pressure is adjusted accordingly; for example, if you sleep on your back the machine will increase the air pressure, and when you sleep on your side, it will lower it. The machines are even designed to have Mask Off Alert in the case of restless sleepers.
  • APAP machines provide by far the most comfortable PAP therapy. The mask and tubes are often very comfortable and generally fit better. This prevents air leakage as well as dryness in the nose and mouth. Moreover, there are rarely rashes and skin marks from the mask.

Possible Disadvantages To APAP Therapy

Here are some possible and common complications that can occur during APAP therapy;

  • Slow adjustments – it has been noted that pressure adjustments can be rather slow in some cases, which can cause sleep interruptions. Some patients have reported diminishing sleep quality due to the APAP machines making several adjustments throughout the night, but each adjustment would take time and wake them up.
  • Not suitable for everyone – even though APAP machines are exceptionally useful and beneficial, they may not be suitable for certain patients. For example, people who suffer from chronic heart failure, chronic obstructive pulmonary disease, or obesity hypoventilation syndrome should not use APAP machines for therapy.
  • Not for central apnea – APAP machines have been shown effective with obstructive sleep apnea, but its interaction with other apnea syndromes, like central apnea, has not been studied yet.

BiPAP Vs. CPAP Vs. APAP: Which PAP Machine Is The Best For You?

BiPAP machines are excellent for people who have breathing problems that require variable, or different pressure levels. It is best used for respiratory weakness, sleep apnea, daytime sleepiness, treatment of sleep disorders, and improvement of health overall.

The machine has shown very effective in cases of shortness of breath, amyotrophic lateral sclerosis, fatigue, insomnia, etc. Because the machine delivers different pressures on inhaling and exhaling, it also provides a less invasive therapy compared to CPAP devices, so many patients seem to prefer it over CPAP devices.

CPAP machines are more suitable for patients who don’t experience drastic changes in breathing patterns during sleep. These devices are also leading treatment options when it comes to obstructive sleep apnea, as they show maximum effectiveness and fast results.

Sometimes CPAP therapy shows exceptional improvement in only two weeks. The device is also suitable in cases of snoring and general breathing difficulties, and it also improves your heart health, diabetic control, and general health.

APAP machines are suitable for people who have particular breathing patterns, changes in breathing patterns, and require a device that will detect and act accordingly to the changes. It is also suitable for people who are restless sleepers or like to sleep on their side or back throughout the night.

APAP therapy has also shown effective in cases of allergies, cold, respiratory infections, and congestion. Unlike the previous two PAP machines, this one can detect the smallest, most subtle changes in breathing and automatically adjusts the air pressure. So, if you’re looking for such a device, then the APAP machine would be best for you.

Now, your doctor is the only person to know which PAP machine is the best for you. The machine is selected in accordance with your medical history, current health situation, and breathing requirements.

However, the more educated you are on this topic, the better your discussion with a doctor will be. You can explain your preferences and what is it that you’re looking for in a machine.

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