A continuous positive airway pressure (CPAP) machine is commonly known to be useful in addressing respiratory conditions. Though CPAP is most commonly associated with managing sleep apnoea, it is also shown to be useful in other conditions such as chronic obstructive pulmonary disorder (COPD), asthma, and pneumonia.
In short, CPAP can be suitable for addressing a wide range of conditions associated with the following symptoms:
What is sleep apnoea?
Obstructive sleep apnoea (OSA) involves periods of an obstructed upper airway, which can involve a complete or partially collapsed airway. An obstructed airway during sleep can occur when individuals are obese or have an enlargement of tissues in their airways, such as the tonsils or soft palate. OSA can, therefore, cause decreased oxygenation and disruption of sleep. Though seemingly harmless, OSA can affect cardiovascular health, mental health, and quality of life.
The relationship between OSA and cardiovascular health is particularly seen in the context of pulmonary hypertension (PH). Due to the airway collapse, the oxygen saturation decreases. This results in the remodelling of blood vessels in the lung, where they constrict (become smaller) due to changes in the levels of mediators such as endothelial nitric oxide synthase (eNOS) and vasoactive mediators, such as endothelin-1 and NO. As the blood vessels in the lung become smaller, the blood pressure to get them across increases, causing PH.
Do I need a CPAP?
Having understood sleep apnoea and its long-term implications, it is important to identify individuals who will benefit from CPAP. Given that the primary condition associated with CPAP use is sleep apnoea, identifying if one will benefit from CPAP use is heavily associated with whether an individual is diagnosed with sleep apnoea. Diagnosis of sleep apnoea will typically require one or more of the following symptoms and tests:
Performing tests such as home sleep tests is necessary before the use of CPAP since it aids in the diagnosis of sleep apnoea and/or rules out other potential conditions, such as central sleep apnoea. Management strategies (such as CPAP) will only be discussed after these tests.
Beyond identifying symptoms or signs that can make CPAPs useful, it is necessary to recognise factors that make an individual unsuitable for CPAP use. CPAP should not be used in:
How does CPAP work?
The CPAP machine is made up of numerous components:
This positive pressure of air helps keep the airways open since they can ‘collapse’ in some respiratory conditions mentioned previously (COPD, asthma, sleep apnoea). Keeping the airways open, more air (and therefore oxygen), can reach the bottom of the lungs where the alveoli reside. The alveoli are key structures in the lung that enable gas exchange, promoting oxygenation and removing waste materials such as carbon dioxide from the blood.
How is a CPAP used?
Using a CPAP (if necessary) is fairly straightforward, but there are some key things to be aware of to ensure proper usage:
Given that CPAP is predominantly used for sleep apnoea, it is likely that most individuals will only have to wear it at night.
How does CPAP help?
Should one need a CPAP for sleep apnoea or other respiratory conditions, they are likely to observe the following benefits:
A study published in 2001 summarising other publications reported that CPAP is effective in managing obstructive sleep apnoea, one of the key respiratory conditions CPAP is typically used in. Individuals who used CPAP showed:
Types of CPAP
There is some flexibility in the use of a CPAP. Recognising that a wide range of users are likely to use CPAP for conditions such as sleep apnoea, CPAP’s mask/ headgear component has numerous designs. Some common designs include:
These days most CPAP machines provide automatic positive airflow pressure (APAP). Please note that CPAP machines are different from Bi-level positive airflow pressure (Bi-PAP) machines.
This machine monitors the user’s breathing throughout the night and automatically changes the air pressure to maintain the integrity of the airway to allow for easy breathing.
Bi-PAP has two different pressure settings: one for inhaling and another for exhaling. It is used in individuals who cannot use regular CPAP machines or have high carbon dioxide levels in their blood.
These machines can also address sleep apnoea and other respiratory conditions but have slightly different mechanisms in terms of the air pressures used.
Is CPAP the only option?
CPAP can seem like a major change, or individuals may feel claustrophobic. There are other alternatives for CPAP. This can include other treatments:
Here are some key takeaways:
Concerned you may have sleep apnoea or OSA?
Both OSA and sleep apnoea can profoundly affect your physical and mental well-being. It is important to contact the right doctors and dentists if you think you may be struggling with your sleep or breathing. If left untreated or unchecked, OSA and sleep apnoea can cause other health conditions, such as strokes and hypertension.
As a leading sleep and respiratory physician specialising in OSA and sleep-related breathing disorders, I offer consultations to diagnose and treat these conditions, including CPAP. Please contact me if you have any further queries about sleep apnoea or want further advice on potential treatments such as CPAP and mandibular advancement devices.
