Continuous Positive Airway Pressure (CPAP)


Published: 06 June 2021

Working in healthcare, you may interact with and care for clients in the community (e.g. aged care and home care settings) who use CPAP machines.

This article will provide a refresher on how CPAP machines work and caring for clients using them.

What is Continuous Positive Airway Pressure (CPAP)?

Continuous positive airway pressure (CPAP) is a type of non-invasive ventilation commonly used to treat moderate to severe obstructive sleep apnoea (OSA) (Nickson 2019; Healthdirect 2020).

A CPAP is often the first-line treatment for OSA in adults and is considered the most effective non-surgical intervention (UOM 2020). Clients can use a CPAP themselves in an outpatient or home setting (Pinto & Sharma 2021).

OSA causes partial or complete obstruction of the airway during sleep, causing the client to stop breathing, wake up and then go back to sleep. This process may repeat hundreds of times in one night (Healthdirect 2020).

Read: Obstructive Sleep Apnoea: More Than Just a Bad Night's Sleep

A CPAP machine works by administering a steady stream of airflow into the client’s airway, maintaining a continuous pressure that functions as a stent to keep the airway open throughout the night (Pinto & Sharma 2021).

As well as preventing the airway from collapsing, a CPAP increases the ability for oxygen to enter the lungs and fill alveoli sacs. This is where gas exchange occurs and allows carbon dioxide to be removed. (GOSH 2017).

There are three components of CPAP:

cpap machine
  1. A machine to pressurise the air
  2. A facial mask (‘interface’) that the client wears at night
  3. A hose that connects the machine to the mask in order to deliver the pressurised air to the client.

(GOSH 2017; Sleep Foundation 2020)

Headgear (straps or a mesh cap) is used to hold the mask in place and create a seal around the nose and/or mouth (GOSH 2017).

Types of CPAP Masks

A CPAP can be administered using one of several types of interfaces. It is important to determine which type of interface is most appropriate for the client’s needs:

Type of interface Description May be appropriate for: Image
Nasal pillow mask A small mask that sits over the nostrils, or nasal prongs that sit directly inside the nostrils.
  • Clients who feel claustrophobic wearing bigger masks
  • Clients who want a full field of vision
  • Clients who wear glasses
  • Clients with facial hair
Nasal mask (nasal continuous positive airway pressure or NCPAP) A mask that covers the nose only. This is the most common CPAP interface.
  • Clients who have been prescribed a high air pressure setting
  • Clients who move around in their sleep
Full-face mask A full-face mask that fits over the nose and mouth.
  • Clients who have difficulty breathing through their nose due to nasal obstruction or congestion
  • Clients who breathe through their mouth at night

(Pinto & Sharma 2021; Mayo Clinic 2015; UOM 2020)

Humidifier Chambers

Some CPAP machines have a humidifier chamber, which moisturises the air that is being delivered to the client. This reduces side effects including mouth and throat dryness, nosebleeds, runny nose and congestion (Sleep Foundation 2020; Pinto & Sharma 2021).

Humidification is important as the air delivered by a CPAP machine enters the airway too quickly for the nose to naturally warm it. Humidified air is more comfortable to breathe, less damaging to the tissue in the upper airway and lungs and less likely to wake the client up (ResMed 2020).

Contraindications for CPAP

The following clients are not suitable for a CPAP (note: escalation of care is crucial in these situations):

  • Clients who are not breathing on their own
  • Clients who are unconscious
  • Clients who are uncooperative or severely anxious
  • Clients with a reduced level of consciousness who cannot protect their airway (should not be used for clients with a GCS score of eight or less)
  • Clients with an unstable cardiorespiratory status or those experiencing respiratory arrest
  • Clients with facial trauma or burns
  • Clients who have undergone facial, esophageal or gastric surgery
  • Clients with air leak syndrome (pneumothorax with bronchopleural fistula)
  • Clients with excessive respiratory secretions
  • Clients with severe nausea and vomiting
  • Clients with severe air trapping diseases with hypercarbia asthma or chronic obstructive pulmonary disease (COPD).

(Pinto & Sharma 2021; QAS 2017)

Benefits of CPAP

The use of a CPAP may:

  • Reduce the work of breathing
  • Minimise the use of accessory muscles when breathing is difficult
  • Improve pulmonary gas exchange
  • Decrease intubation rates
  • Decrease the length of hospital stays
  • Reduce sleep disruptions
  • Improve the quality of sleep
  • Prevent snoring
  • Reduce sleepiness during the day
  • Reduce headaches in the morning
  • Improve functioning during the day
  • Improve the quality of sleep for the client’s partner.

(GOSH 2017; UOM 2020; QAS 2017; Stanborough & Dasgupta 2020)

Disadvantages of CPAP

  • A CPAP may cause side effects, including congestion, runny nose, dry mouth, sore throat, hypotension, dry cornea, barotrauma, respiratory infections, chest discomfort, excessive dreaming (initially) and nosebleeds
  • Clients may initially experience feelings of discomfort, claustrophobia or embarrassment
  • The CPAP mask may cause skin redness, irritation or pressure injuries on the face
  • Clients may initially experience discomfort in the morning after using the CPAP
  • The CPAP mask and hose require regular cleaning, inspection and replacement every three to six months
  • Clients may experience abdominal distension or bloating, which may lead to nausea, vomiting and aspiration
  • Poorly fitting masks may leak
  • Lack of client compliance is common. This may be due to the education they are receiving.

(Pinto & Sharma 2021; UOM 2020; QAS 2017; Sleep Foundation 2020)

cpap disadvantages discomfort
Clients may initially experience discomfort when using the CPAP.

How to Set Up and Use a CPAP Machine

  1. Find an appropriate place to put the CPAP machine. It should be on a stable surface, close to the bed, close to a power outlet and have unobstructed access from the bed. Nightstands and bedside tables are good choices.
  2. Check the filter (see the written instructions).
  3. Attach the hose to the machine, using the special connector. The hose should stay in place easily.
  4. Plug the hose into the mask. It should fit tightly and may click into place.
  5. If the CPAP has an attached humidifier, fill it with distilled water up to the maximum fill level.
  6. Plug the CPAP machine into a power outlet.
  7. Put the mask over the face, then attach or pull the straps to secure it into place. This should create a seal without pinching the skin. Adjust the length of the straps if needed.
  8. Turn on the device (an appropriately qualified healthcare worker should have already set the correct pressure settings).
  9. Tighten the mask if you hear air escaping.

(Sleep Foundation 2020)

How to Clean a CPAP Machine

  • Every week, and whenever contaminated with secretions, clean the mask and hose using warm, soapy water. They should be left to air dry.
  • If the CPAP machine has a humidifier, the distilled water should be emptied and replaced daily before use.
  • If the humidifier chamber has limescale build-up, soak it in vinegar and water for 10 minutes, rinse thoroughly and then air dry.
  • Replace the filter whenever it becomes discoloured (generally every three months).

(GOSH 2017)

cpap mask hose cleaning
The CPAP mask and hose should be cleaned with warm, soapy water every week.

Caring for Clients Who Use a CPAP Machine

The following practical tips may help you to care for clients who use a CPAP machine:

  • Understand that clients may take a while to adjust to the CPAP at first
  • Always exercise patience, empathy and thorough, gentle education around the implementation of the device
  • If the client is resistant to using the CPAP, determine what exactly they dislike, e.g. the mask or the pressure
  • Encourage clients to use the CPAP every time they sleep
  • Encourage anxious clients to try relaxation techniques before using the CPAP, or to practice using the mask while they are awake
  • Encourage the client to wash their face prior to using the CPAP, as this will assist in creating a seal and help to prevent skin irritation
  • Ensure the client’s mask fits properly and consider trying different interfaces that may be more suitable
  • Consider using a CPAP machine with a ‘ramp’ feature, which allows air pressure to gradually increase as the client falls asleep
  • Consider a nasal saline spray for clients who are experiencing a dry or stuffy nose
  • If the client has a habit of unintentionally removing the mask during the night, consider setting an alarm to check that it is still on
  • Encourage the client to avoid caffeine and alcohol before bedtime so that they are able to fall asleep more easily
  • Ensure the mask is clean and dry before the client wears it.

(Sleep Foundation 2020; Mayo Clinic 2018; GOSH 2017)

The Importance of Client Education

Appropriate client education is crucial in ensuring compliance, and subsequently, long-term success. It’s important to monitor the client’s compliance, especially when they are first commencing CPAP therapy, as many people stop treatment prematurely due to discomfort (Pinto & Sharma 2021).

Encourage clients to inform you of any adverse effects they are experiencing and ensure these are addressed by an appropriately qualified clinician. It’s also important to make sure that the CPAP machine is checked regularly and the mask fits properly (Pinto & Sharma 2021).

In addition to providing continuing client education on the benefits of regular CPAP use, clients should also be encouraged to take other measures to improve the effectiveness of treatment, including:

  • Maintaining a healthy weight
  • Maintaining a healthy diet
  • Exercising regularly
  • Avoiding smoking.

(Pinto & Sharma 2021)

Additional Resources


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