Continuous positive airway pressure (CPAP) machines are used to maintain an open airway in patients diagnosed with obstructive sleep apnea. The machine functions by blowing pressurized air into the airway via mask at a setting determined by sleep study and prescribed by a physician. This pressurized air can cause patients to suffer from dry and irritated noses, dry mouths, and sore throats. A CPAP humidifier can add moisture to the air introduced with the CPAP and may help decrease discomfort.
The continuous flow of air from a CPAP machine can be irritating to the tissues of the nose, mouth, and throat. This irritation may result in nosebleeds, increased mucous, congestion, and coughing or sneezing. The main reason for the irritation is the drying effect of the pressurized air. Adding a CPAP humidifier to the device increases the moisture of the air delivered through the mask.
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In many machines, a passive humidifier attaches to the CPAP. The pressurized air is run through the cold water before progressing through a short hose to the CPAP and then through a hose to the mask, taking water molecules with it. This type of humidifier is minimally effective for devices with higher pressures. In cooler environments, the moist air may feel uncomfortably cold as it passes through the mask.
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Some humidifiers utilize heat to create moisture. A heated water container is connected in the same way as the passive humidifier. The heat allows the air to hold more moisture and thus carries more effectively humidified air to the patient. A heated CPAP humidifier is usually adjustable so that the patient can fine-tune the humidity to his or her individual comfort level.
Either type of humidifier may be available as an integrated unit. An integrated humidifier is offered as a component part attached directly to the CPAP machine. This type of humidifier is smaller and eliminates the need for additional hoses and power cords. Integrated units are generally specific to and compatible with only one CPAP machine. In other words, if a new machine is purchased, an older humidifier may not work with it.
A stand-alone humidifier is a universal module and can be connected by a short hose to most CPAP machines. The water chamber is often larger than in other units. This is both an advantage, in terms of improved humidity, and a disadvantage, as the equipment is often larger and bulkier.
Some humidifiers are built right into the CPAP. Other than the water tank that is removable for filling and cleaning, the humidifier and CPAP are a single unit and cannot be separated. This eliminates the need for extra hoses and power cords, and often is a much smaller piece of equipment.
A CPAP humidifier can make the machine more comfortable for a sleep apnea patient. Moister air keeps mucous membranes hydrated. This reduces irritation and often improves the overall CPAP experience for patients.