Continuous Positive Airway Pressure (CPAP) Machines

Sleep Disorders

CPAP Machines

What are Continuous Positive Airway Pressure (CPAP) Machines?

They are machines that are widely used to deliver pressurized air to help patients with obstructive sleep apnea (OSA) breathe, particularly when they are asleep. These are patients who suffer from narrowing or collapse of their air passages during sleep, causing breathing to stop (apnea) or get markedly reduced periodically (hypopnea).

There are two major types of CPAP machines: Nasal CPAP and Bilevel positive airway pressure, or BiPAP. In nasal CPAP, the airway pressure delivered into the upper airway is continuous during both inspiration and expiration. BiPAP differs from CPAP in that the pressure during expiration may be adjusted separately from the pressure delivered during inspiration.

How do you wear them at night?

The machine pumps air under pressure, which is delivered usually through snugly fitting masks over their nose. The masks may also cover the mouth, and parts of the face and forehead, depending on the design.. They are held securely in place by headbands or tapes, throughout the duration of sleep. ‘Nasal pillows’ are one variation in design, where air is delivered directly inside the nostrils through small cushions, without anything on the face.

How much pressure or flow can they generate?

CPAP machines can generate a range of pressures above atmospheric pressure, typically between 4 and 20 centimetres of water. The average patient however requires between 6 and 14 centimetres of water pressure, and individual pressure requirements are calculated for patients after a sleep study in a sleep laboratory. Modern CPAP machines can also incorporate computerized patterns of varying pressure depending on air flow (auto-CPAP).

Air flow rates can also be varied between 20 to 60 liters of air per minute on most machines, depending on one’s airway resistance and tidal volume ( average volume of air inhaled or exhaled per breath). The airflow rate that is appropriate for you is one that allows the oxygen levels in your blood to be kept at normal levels. Again, your sleep laboratory or physician will help you in this regard.

Do you need your doctor’s approval to get one?

Yes you do. CPAP machines cannot be sold without your doctor’s prescription. More importantly, sleep apnea is linked to several serious health problems, and it is very important that you are under medical supervision if you suffer from it.

How much does they cost?

CPAP machines come in a wide price range – starting at around $150, going up to $5000 or more. The more expensive models usually incorporate alarms, medical data recording facilities, adjustable ventilator setting suitable for a wide range of disorders. Check with your doctor or laboratory about the features you need, before you choose which models to buy.

Can I get portable CPAP machines which I can carry with me?

Yes certainly. CPAP machines come in a variety of shapes and sizes, and most are portable - which makes it easy for us to carry with us wherever we go. In addition, small compact machines are available, specifically created for easy travelling, with rechargeable battery packs and chargers. Adapters for power sockets on most commercial flights are readily available – but check with the airline representative before you go.

Are there any other important things I need to know?

Humidifiers are essential for some CPAP users, who get uncomfortably dry noses and throats. Your face mask can easily be modified to use one, or you can but a face mask with built-in humidification.

Only a very small number of patients find it impossible to use CPAP machines – if you find it difficult to use at the beginning, check with your doctor or sleep lab, small adjustments can easily solve the problem in most instances