For moderate to severe obstructive sleep apnoea (OSA) wearing what is known as a CPAP mask is recommended during the night. According to the German Society for Sleep Research and Sleep Medicine (DGSM), this is currently the standard therapy.1 CPAP stands for: continuous positive airway pressure.
The technical equipment consists of a breathing mask that is connected to the CPAP ventilator via a flexible tube. The CPAP machine, which is placed next to the bed, draws in ambient air, filters it and pumps it under positive pressure into the airways. In this case, the patient breathes in completely through the mask and also breathes out again through the mask against this pressure.
Three different types of masks are commonly used:
- Full-face masks cover the mouth and the nose. They are often used for patients with nasal obstruction, mouth breathers and high pressure therapies.
- Nasal masks sit over the nose. They are smaller and also lighter than full-face masks.
- Nasal pillow masks consist of two end pieces made of soft plastic that are inserted into the nostrils. This leaves the face as free as possible. However, this type of mask is only suitable if a very low positive pressure is therapeutically sufficient.
All masks have a ‘leak valve opening’. A small amount of air continuously flows out through this, including exhaled air. So a certain ‘leakiness’ is correct and important.
How does CPAP therapy work?
This is how CPAP therapy works: The positive pressure of the breathing air prevents breathing pauses during sleep, which are typical of obstructive sleep apnoea. During sleep, the muscles relax, which may cause the upper airways to collapse. This interrupts the flow of breath. In addition, if the muscles become slack, the tongue can slip into the throat and block access to the windpipe.
Each pause in breathing triggers arousal from sleep, which subconsciously helps the body to stabilise itself again. This is over in seconds and the sleeper usually doesn’t notice this. Although he or she does not actually wake up, the present sleep phase is disrupted, blood pressure and heart rate briefly increase before the sleeper returns to a restless sleep. The consequences of the repeated nocturnal breathing stops are felt the next morning people with obstructive sleep apnoea syndrom (OSAS) wake up feeling tired and are constantly unrefreshed by sleep during the day.
Normally, there is negative pressure in the upper airways when you breathe in during sleep. This negative pressure increases the risk of the slackened muscles collapsing and/or the tongue slipping backwards. Ventilation with slight positive pressure therefore appears to be a suitable therapy for OSAS in order to stabilise the muscles and prevent dangerous breathing cessations.
This actually works: Nocturnal ventilation via a CPAP mask has been shown to be able to keep the airways open. Breathing stops occur much less frequently or no longer at all. The oxygen content of the blood increases, the body is better supplied with oxygen again. The quality of sleep improves and daytime sleepiness decreases.2 And there is another positive side effect that particularly benefits the sleeping partners: Snoring usually stops with positive pressure ventilation.
Possible secondary diseases of obstructive sleep apnoea include high blood pressure, heart attack and stroke. Studies have shown that CPAP therapy can normalise blood pressure.2,3 It is unclear whether this treatment can also reduce the risk of heart attack and stroke in those affected by OSA.
A large study of almost 3,000 people affected by OSA (with coronary heart disease) showed no protective effect of CPAP therapy in terms of heart risk.4 This came as a surprise, as sleep quality and Apnoea-Hypopnoea Index (AHI) improved significantly in the study. The AHI as a measure of the number of breathing stops decreased from an average of 29.0 to 3.7 events per hour. The breathing disorder typical of OSAS can therefore be effectively treated by CPAP ventilation.
Effects of CPAP ventilation at a glance:
- The dangerous breathing pauses typical of OSAS are reduced
- The oxygen content of the blood increases
- Snoring decreases
- Elevated blood pressure is lowered
Why many sufferers reject the CPAP mask
The effectiveness of CPAP treatment is undisputed, but only under one condition: This is a long-term treatment and the mask must be used every night, sometimes for the rest of your life. However, studies show that not even half of all people affected by OSA follow their doctor’s instructions.5
CPAP mask and device interfere with sleep
Many people experience wearing the mask as uncomfortable and disturbing.7 This is partly due to the continuous air pressure when breathing in and out. Many find it difficult to exhale against the air pressure. Some find this exhausting and quickly.
The following application errors often jeopardise the success of the therapy:
- The mask is often not properly fixed in place. It must fit tightly, otherwise air can escape from the sides. This should not happen because then it cannot be ensured that the breathing air really flows into the airways with positive pressure.
- Many users also complain of red or dry eyes due to an ill-fitting CPAP mask or leaks. The air that escapes during sleep can even cause eye inflammation or conjunctivitis.
- Many people do not wear the CPAP mask long enough. They put the mask on before going to sleep, but then take it off again during the night. The recommended minimum – five hours per night – is thus often undercut.6 In the worst case, treatment is even discontinued altogether and the CPAP device ends up in the storeroom.
Anxiety and loud noises due to the CPAP
In addition, many find it difficult to fall asleep and/or sleep through the night with the technical equipment. The mask creates anxiety. Dry mouth and nose, as well as other side effects and problems with the use of the CPAP mask, also cause users to feel uncomfortable with this therapy. Finally, the technical noise of CPAP therapy can also be an obstacle.
In other words: CPAP therapy, which is supposed to help the person get a restful night’s sleep, can in turn severely disrupt sleep. In addition, many are put off by the prospect of having to sleep with this technical equipment all the time – for the rest of their lives. Partners of OSAS sufferers also find this idea irritating and do not always support CPAP treatment, although they experience its effectiveness in terms of snoring as very liberating."
Common side effects and problems with the CPAP mask
Most CPAP masks have a standardised shape and cannot be customised. So it may happen that the mask does not fit properly or slips during sleep and air escapes. The positive pressure of the breathing air required for therapy is then no longer ensured.
In addition, the escaping air flow can lead to eye irritation and even conjunctivitis. Painful pressure sores and pressure ulcers can also be potential consequences if the CPAP mask does not fit. The escaping air can also disturb the bed partner and, in the worst case, lead to colds. In addition, healthy sleep is severely disturbed for both sufferers and their partners.
Switching to a different mask is worth a try, but it does not always eliminate the problems. Please discuss this with your doctor. Alternative treatments should also be taken into consideration.
Breathing out against the continuous positive pressure of the CPAP ventilator is not like natural breathing. Therefore, breathing with a CPAP mask is often perceived as very strenuous and uncomfortable. Some even experience a feeling of breathlessness. If those affected cannot remove the mask quickly enough in this situation, anxiety and panic attacks can even develop.
Many feel constricted by the breathing mask. The mask must fit tightly so that no air can escape at the edge. The rubber bands that hold the mask in place must therefore be relatively tight. Even when set ‘as loose as possible’, the pressure is still oppressively uncomfortable for many. Many people therefore have to get up every night to take off the CPAP mask.
Other reasons for discomfort & panic attacks when wearing the CPAP mask may be:
- previous negative experience, e.g. ventilation via a mask in hospital.
- concern about possible strangulation from the headgear of the mask
- the annoying weight of the CPAP mask.
- the feeling of a foreign body in the face, especially with full-face masks
- panic caused by the cold air coming out of the mask.
To alleviate claustrophobia and possible panic attacks caused by CPAP, it is helpful to be aware of the following facts:
- The CPAP ventilator always pushes in air to breathe
- Claustrophobic anxiety often arises because the ventilator wants to continuously push air into the person. But this is exactly the important air to breathe and prevents the dangerous closing of the airways. The risk to health is considerably greater without a CPAP mask
- Practicing with the CPAP mask during the day can help, e.g. in front of the TV or while reading.
- There are alternative treatments, so don’t put yourself under pressure. But don’t give up too quickly either. Getting used to the CPAP mask takes time.
Common side effects of CPAP therapy, such as dry mouth/throat and dry/blocked nose, are caused by the increased flow of breathing air through the CPAP mask. In particular, breathing through the nose can be difficult due to the increased pressure. As a result, the nose is often blocked and nosebleeds may occur. In addition, a lack of moisture can negatively influence the natural germ spectrum of the mouth and throat. Numerous bacteria and other microorganisms that are useful for us normally colonise our mucous membranes. If their spectrum changes, this can lead to bad breath, among other things.
In addition, dry mucous membranes of the nose and mouth cannot optimally fulfil their barrier function in the defence against pathogens. There is evidence that CPAP ventilation increases the risk of upper and lower respiratory tract infections.8,9 To prevent the mucous membranes from drying out, the use of humidifiers that can be connected directly to modern CPAP machines is recommended as a preventive measure.7
The consultant should monitor whether the pressure is set correctly – i.e. neither too low nor too high. This is because mouth breathing often increases with CPAP, as the open mouth compensates for the more difficult breathing through the nose. This is problematic, because breathing through the mouth not only dries out the mucous membranes, but is also unhealthy for other reasons. Sleeping with the mouth open causes the mucous membranes to produce more mucus to counteract the dryness, which makes the nose even more congested, which in turn promotes mouth breathing. In addition, mouth breathing also leads to bad breath and, in the worst case, to tooth decay. A dry mouth deprives the teeth of their natural saliva layer, which encourages bacterial foci and causes bad breath. It is best to breathe through your nose while using a CPAP mask. This reduces adrenaline release and increases oxygen saturation in the blood. Snoring and breathing pauses are also reduced.
Another major disadvantage of mouth breathing: The body misses out on nitrogen oxides that are produced naturally in our sinuses when we breathe through the nose. Nitrogen oxides are significantly responsible for endurance and strength of the muscles and regulate blood pressure as well as sleep quality because they dilate the blood vessels.
If dry mouth persists despite mask replacement and adjustment of positive pressure, other aids or alternative sleep apnoea treatment should be used.
Muscle soreness in the chest can be a side effect of CPAP therapy, with which the respiratory muscles react to positive pressure ventilation. The lungs must constantly work against increased pressure during CPAP ventilation. This unusual effort can provoke a strain of the respiratory muscles in the chest.
If the pressure of the CPAP machine is too high, the user may swallow air and some of the air may not enter the airways but pass through the oesophagus into the gastrointestinal tract.
Abdominal pain, bloating and flatulence are possible consequences of this. This can only be avoided by restricting the excess pressure. On the other hand, the pressure must not fall below the therapeutically required level, otherwise the nocturnal breathing pauses will continue to occur. The dangerous consequences and risks of untreated sleep apnoea then remain. Sleeping with the upper body elevated and avoiding eating and drinking late at night can help alleviate the symptoms of CPAP bloating.
Other causes of bloating due to a CPAP mask:
- Hyperventilating: Particularly in the case of medium to high breathing pressure, the difficulty in exhaling can possibly lead to anxiety and panic with hyperventilation, in which air is swallowed and bloating results.
- Open mouth: So-called mouth breathers sleep with their mouths open at night. However, if a patient with an open mouth now wears a CPAP nasal mask, the air pumped by the sleep apnoea device can escape through the mouth. There is an unconscious panic reaction and the feeling of suffocating, meaning the air is inhaled too quickly and forced into the oesophagus. In this case, the mask type should be changed to a full-face mask.
- Rhinitis or nasal congestion: Whether it’s a runny nose or a blocked nose. Flu, colds and allergies mean you can’t take the extra pressure needed to keep your airways open. Air is swallowed, which leads to bloating.
- Air pressure too low: Not only too much pressure can lead to flatulence. If the pressure is too low, the nocturnal breathing pauses will continue. The need for more air in the lungs may also result in air being swallowed.
Some people feel disturbed by the noise of the CPAP machine during sleep. Noise also emanates from the mask valve. Wearing earplugs, which is recommended for noise-sensitive people, is of limited use, as it can impair sleep. The bed partner’s sleep also suffers due to the noise. Often this side effect of the CPAP mask leads to relationship problems and separate beds.
Can CPAP therapy also be used by people with colds or hay fever? Mucus in the airways and a blocked nose can make breathing with a CPAP mask more difficult. In the case of a common cold, the treatment may be paused for a short time. The situation is different with hay fever, which sometimes lasts for months. There is no satisfactory solution to this problem. In any case, if you have a blocked nose, it is advisable to wear a full-face mask that covers your mouth and nose. These in turn can lead to the side effects mentioned above such as dry mouth and pressure sores, as well as leaking air if the CPAP mask does not fit.
CPAP masks should be cleaned after each use. This is because germs attach themselves very quickly to the plastic masks and are inhaled if they are not removed regularly. Dangerous pathogens that cause pneumonia, for example, can also enter the respiratory tract via contaminated masks. Therefore, the manufacturer’s recommendations should be followed very carefully when cleaning the CPAP.
CPAP masks are not sexy. Many partners feel irritated and disturbed by the technical equipment. Some of those affected even report relationship crises. The very thought of having to wear a ventilator and mask night after night for the rest of their lives frightens many patients and their relatives. But this is the only way that positive pressure therapy can lead to success.
Puffy eyes, dark circles and unsightly bags under the eyes are a common side effect of CPAP therapy. This is mainly due to incorrectly adjusted full-face masks, which can exert pressure under the eyes and next to the nose.
A leaky CPAP mask can also be the cause, as tiny air leaks can irritate the eyes. If cold exhaled air is constantly getting into the eyes, they will dry out and swell. There may be additional problems with the tear glands, sinuses or eyelids. The exhaled air can cause fluid to build up around the eyes if it enters these ducts.
The first thing to do here is to remain patient. CPAP therapy takes time. Once a mask is found that fits properly, these side effects often disappear on their own.
What to do about bags under the eyes and puffy eyes:
- Place a metal spoon in the freezer for a few minutes.
- Press the cold spoon on the swelling for a few seconds, moving it slightly.
- Apply alternately to both eyes until the spoon is warmer again.
- Change from full-face mask to nasal mask or nasal pillow mask, unless you are a mouth breather, i.e. sleep with your mouth open.
- The CPAP nasal mask relieves pressure, lymph fluids can drain better and do not accumulate under the eyes.
- Before sleeping, put a plaster on the empty bags under the eyes. This prevents the tissue from filling with fluid during the night.
If you still feel constantly tired and your snoring persists, this might be a sign that the breathing pauses are not successfully stopped by the CPAP mask. This means that your daytime performance continues to be impaired and the risk of secondary diseases remains high.
In this case, you should consult a doctor and discuss possible alternatives.
What to do if CPAP therapy fails?
Give yourself some time. It is normal that you find it annoying at first to wear a mask while sleeping. After a while, however, you should get used to it. However, if you still feel unwell and impaired after several weeks, you should discuss this with your doctor.
If you suffer from side effects of CPAP therapy – for example, anxiety, dry mouth, partnership problems – you should not discontinue treatment on your own. There are solutions to some problems. For example, a humidifier can help with dry mouth and a mask change can help with pressure points.
However, if you cannot cope with CPAP ventilation in the long term, you should talk to your doctor about alternative treatment options, such as an upper airway stimulation device.
A good alternative: upper airway stimulation
Long-term treatment, which is required for chronic sleep apnoea, must not only be effective. Compatibility and comfort must also be right. In this respect, nocturnal ventilation with a CPAP mask does not score highly.
Treatment with an upper airway stimulation device can be offered as an alternative. The system continuously measures the breathing rhythm of the user. It stimulates the tongue muscle and prevents it from slipping backwards when it is slack and blocking the airways. The breathing stops typical of OSA are thus avoided. As a result, daytime tiredness decreases and performance increases again, which has been documented in studies with many thousands of people affected. Satisfaction with Inspire therapy is over 90 percent.10 This is not only due to its proven effectiveness, but also because Inspire therapy – unlike CPAP therapy – adapts to natural breathing and allows free inhalation and exhalation during the night. The implant is not visible from the outside and is activated simply by pressing a button before going to bed.
How Inspire therapy works
Thanks to the Inspire therapy, more than 75,000 patients worldwide can sleep through the night again. Inspire therapy is a fully implantable, proven effective and safe system for sufferers of obstructive sleep apnoea who cannot be treated or are not adequately treated with CPAP.
Upper airway stimulation works in harmony with your natural breathing rhythm and significantly reduces nocturnal breathing pauses – completely without a CPAP mask. With a remote control, the patient switches upper airway stimulation on at the touch of a button before going to bed and off again in the morning after waking up. The eligibility of those concerned is checked in medical examinations by a doctor. The procedure is performed in specialised treatment centres and clinics.
You are eligible for Inspire therapy if
- You have moderate to severe obstructive sleep apnoea.
- CPAP therapy is not working sufficiently well for you or the mask is causing problems.
- You are not too overweight (Body Mass Index (BMI) below 35).
In this case, the costs for the innovative therapy will be covered by the national health insurance funds.
References:
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2 Bratton DJ, Gaisl T, Schlatzer C et al. Comparison of the effects of continuous positive airway pressure and mandibular advancement devices on sleepiness in patients with obstructive sleep apnoea: a network metaanalysis. Lancet Respir Med 2015;3(11):869-878.
3 Bakker JP, Edwards BA, Gauta SP. Blood pressure improvement with continuous positive airway pressure is independent of obstructive sleep apnea severity. Sleep 2014;10(4):365-369 (3).
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