What is CPAP?
The term “CPAP” is the abbreviation for “continuous positive airway pressure”. Translated, it means “continuous positive airway pressure”. This means that a machine generates a pressure in the airways and lungs that is continuously higher than the ambient pressure. However, the machine does not take over the work of breathing, but merely supports it. The patient must therefore still be able to breathe independently.
Normally, when the patient breathes in (inspiration), a negative pressure is created in the lungs, causing air to flow in. When the patient breathes out (expiration), positive pressure ensures that the air is forced back out of the lungs.
CPAP devices constantly pump air into the lungs at a slight pressure. On the one hand, this prevents negative pressure during inspiration; on the other hand, the patient must exhale against increased resistance. Support with CPAP is either invasive, i.e. via a breathing tube, or non-invasive with the aid of a CPAP mask.
Keeping the airway open
When do you perform CPAP ventilation?
CPAP is used for sick people who get too little air without support because either the lungs are damaged or the airways are unstable. However, the prerequisite is always that the patients are still able to breathe on their own.
CPAP in intensive care
In intensive care units, patients often have to be artificially ventilated for long periods of time, and efforts are made to keep this duration as short as possible. When the patient is supposed to breathe on his own again, however, this cannot happen suddenly. This is because the respiratory muscles are weakened after prolonged mechanical ventilation. Instead, patients must be slowly weaned off the ventilator. In medicine, this process is called “weaning.”
CPAP ventilation is an essential element in weaning because, although it helps the patient to breathe, it does not completely wean the patient off the ventilator (as artificial ventilation did previously). As the patient progresses, the pressure of the CPAP device is gradually reduced until the patient is eventually able to breathe again without assistance.
CPAP for sleep apnea
As a result, the patient often wakes up several times a night – restful sleep is no longer possible. Masks with connected CPAP devices can help here because they prevent the upper airways from collapsing.
What do you do with CPAP ventilation?
Most CPAP machines generate positive airway pressure with the help of a tight-fitting mask. When needed, such as in an intensive care unit, you connect it to a breathing tube. Normally, the patient breathes only ambient air. However, if necessary, the devices can also mix in pure oxygen to provide additional support for the patient. Because the continuous flow of air during CPAP therapy would dry out the mucous membranes, the devices also humidify the air breathed.
CPAP machines for private use are similar to those used in an intensive care unit, but they do not have nearly as many functions.
Sleep apnea masks
Simple nasal cannulae, such as those used in hospitals to provide oxygen for breathlessness, are not sufficient for sleep apnea. Several mask systems are available:
- Nasal masks
- Mouth-nose masks
- Full face masks
- Nostril masks
- Respiratory helmet
What are the risks of CPAP?
When used correctly, CPAP ventilation is a harmless therapy. However, problems sometimes occur, particularly in the home, especially when the mask is still unfamiliar. For example, some patients on CPAP therapy complain of dry nasal, oral or pharyngeal mucous membranes. It may then be necessary to humidify the supplied air more.
If the mask accidentally slips during sleep despite the straps being tightened, on the one hand not enough ventilation pressure is built up. On the other hand, the air then often flows past the eyes. In unfavorable cases, this can lead to conjunctivitis.
If the CPAP mask fits very tightly, it may press too hard on the tissue, especially in the cheek area. If the patient or caregiver does not notice this in time, pressure ulcers can develop. In severe cases, surgery may even be required. However, this problem can be prevented by not tightening the straps of the mask too much and also by scheduling regular breaks in CPAP therapy – the mask should never be worn permanently!
What do I need to keep in mind during CPAP therapy?
If the doctor prescribes you a mask, it is important that you allow yourself time to get used to it. It is perfectly normal for sleep to be more restless and less restful than before due to this foreign body. But don’t be discouraged by these initial difficulties. Soon you will feel rested and refreshed in the morning.
Since it is not yet clear at the beginning of CPAP therapy which airway pressure is right for you personally, the doctor will initially start with a low pressure. If necessary, it will be increased. It may be unpleasant for you at first if you suddenly have to breathe against a higher pressure. But again, you will soon get used to the new setting.
If you notice symptoms such as reddening of the eyes or dry mucous membranes during use, you should report this to your doctor immediately. It may then be necessary to switch to a different CPAP mask.
