woman blowing her nose

CPAP Humidifier and Heated Humidifier Explained

Humidification for CPAP machines can lessen nasal congestion, dryness, and rainout, and aids in a more comfortable experience. Many of the new CPAP machines offer integrated humidifiers. They automatically adapt to the amount of humidity present and ambient temperature to provide optimal conditions to the mask. This post answers the question “Is a CPAP Humidifier necessary?” and describes the various methods of CPAP humidification.

 In This Article

  • CPAP Humidifier and Humidification
  • Benefits of Using CPAP Humidification and Heated Tubing
  • Why Recommend CPAP Humidification and Heated Tubing?
  • Improving Compliance With CPAP Heated Humidifier
  • Another Benefit of Heated Tubing with CPAP Therapy
  • Types of CPAP Humidification
  • Difference Between Cool Passover & Heated Humidification
    • Cold passover humidification

    • Heated humidification

    • Integrated heated CPAP humidifier

  • Manufacturers Make it Easy to Add CPAP Humidifiers and Heated Tubing
  • What is HME and HumidX Portable CPAP Humidification?
    • How does HumidX work?

  • Can You Use Regular Water in a CPAP Humidifier?
  • Common Problems that Can Occur with a CPAP Humidifier
  • How do you prevent condensation in CPAP tubing?
    • How do you stop rainout in a CPAP mask?

    • How do you prevent bacteria from growing in a CPAP humidifier?

    • Can I use oils or scents in a CPAP humidifier?

  • Cleaning the Chamber and Tubing is Important Too!

CPAP Humidifier and Humidification

In winter, when heat is typically turned up inside, the natural moisture in the air is decreased. This, in turn, reduces the amount of moisture flowing through a CPAP machine. With the flow from a CPAP machine causing some dryness, the issue of a lower moisture level can aggravate the situation. This lack of moisture within the nasal passages may induce bleeding, swelling, sneezing and congestion. Additionally, a lack of moisture creates a fertile ground for colds or sinus infections. Therefore, humidification is not only a comfort feature. The additional humidification performs an important part of CPAP therapy. It reduces dryness and relieves any inflammation within the nasal passages. In fact, humidification, especially heated, increased patients satisfaction, comfort and, therefore, compliance.

Benefits of Using CPAP Humidification and Heated Tubing

Patients with sleep apnea who use CPAP machines for more than four hours a night enjoy a good night’s sleep and also improve their quality of life. Some sleep apnea patients, unfortunately, find that staying committed to the CPAP treatment process can be a difficult proposition. In particular, it is not uncommon for patients to experience dryness of the mouth, throat or nasal passage . This dryness tends to make the transition to CPAP therapy more challenging than it otherwise would be. This post will not attempt to resolve all CPAP compliance issues; but many compliance issues can be resolved by increasing the humidity during therapy. For instance, air delivered via CPAP averages around 20% lower in humidity than one would find in an average room. In many cases, the CPAP humidification and heated tubing have been shown to improve patient comfort and compliance with CPAP therapy.

Why Recommend CPAP Humidification and Heated Tubing?

When first beginning CPAP therapy without humidification, as many as 40% of patients experience problems like dry throat and nasal passages, congestion and even nosebleeds (1). Sometimes congestion and nosebleeds can be attributed to allergies, rhinitis or sinusitis, but in many cases adding CPAP humidification and heated tubing can alleviate these conditions since they are a side effect of breathing dry, pressurized air. Fortunately, CPAP humidifiers are designed to address these issues. When you use a CPAP machine, pressurized air constantly passes through your airways. As a result, therapy can dry out your nasal passageway or cause irritation. A humidifier adds moisture to the airflow, which reduces the harshness of the air stream and prevents irritation.

Even with a humidifier, patients can still experience dryness and inflammation due to the ambient room temperature. If the room temperature is cold and no heated humidifier is being used, the airflow through the mask will be cold as well. Constant cold air can cause a sore throat or other discomfort. Luckily, heated CPAP humidification and heated tubing can remedy this problem by heating up the air as it passes through the humidifier’s water chamber. In most cases, the combination of heat and moisture alleviates nasal congestion and dry mouth caused by CPAP therapy.

Improving Compliance With CPAP Heated Humidifier

Humidification and heated tubing can truly improve an individual’s CPAP therapy experience. Without dryness, congestion, or irritation, CPAP therapy users are much more likely to remain compliant and use their machines every night. Consistent use of your CPAP device is key to treating sleep apnea and also ensuring you receive plenty of sleep each night. If you have trouble with some of the side effects of using a CPAP machine, humidifiers and heated tubing can deter those issues and help you get on the right track with your sleep apnea treatment.

Another Benefit of Heated Tubing with CPAP Therapy

Surprisingly enough, heated tubing has another benefit as well. When heated air travels from a heated humidifier and cools in a conventional tube, condensation collects on the inside of the tube. If enough water collects in the tube, it can flow up into the CPAP mask. This sudden splash of water in the nose or mouth is also known as rainout and can be annoying. Heated tubing helps to prevent this unpleasant shock by maintaining the warm temperature of the air within the tube. Machines like the Philips Respironics DreamStation have optional heated tubing and heated humidifier accessories that can offset the risk of rainout.

Types of CPAP Humidification

Most new CPAP machines, with the exception of small travel units, have integrated humidification. These units can provide both warm and room temperature humidification through manual controls. Each person is different so it’s best to experiment with the temperature setting on the humidifier. For travel units, an in-line filter can help by capturing humidification from exhaling and returning it back as moisture. Fortunately, the most popular travel unit, the Philips DreamStation Go and the ResMed AirMini portable CPAP addressed the humidification issue with a new integrated humidifier. 

CPAP patients have the option of heated or cold pass-over humidification, or no humidification at all, and they can experiment and choose their best personal solution.

Difference between Cool Passover & Heated Humidification

There are three types of CPAP humidifiers available. Cool pass-over style humidifiers allow the airflow to pass over a pool of water and subsequently pick up water vapor by free evaporation. Typically the larger the surface area of the pool of water the more water vapor the air stream can pick up. Heated pass-over style humidifiers are much more efficient at providing humidification simply by increasing the water temperature, which increases water vapor production vs. free humidification. By increasing the water temperature, additional energy is added to the individual molecules, allowing more of them to transform from the liquid state. As a result, the heated humidifier has the capability to provide additional water vapor to the airstream vs. a typical cool passover design.

Cold Passover Humidification

Cold or “passover” humidification was the first type of humidification therapy for CPAP. It is a water chamber that allows air from the CPAP to “pass over” the water before entering the CPAP tube thereby creating humidified air. This old style set up is effective for CPAP users with low pressure settings and a warm climate. But, it is not optimal. The passover humidifier is typically separate from the machine and needs a separate tube connection adding bulk to the setup. In addition, the amount of moisture is static which might be too little or too much depending on the circumstances. Finally, as the water temperature in the pass over falls, it could become too cold to tolerate throughout a sleep cycle. Instead, CPAP patients have gravitated to the new and more advanced heated, integrated CPAP systems.

Heated Humidification

Heated humidification has become the most popular type of CPAP humidifier. Based on several industry studies, satisfaction, comfort, and compliance jump measurably with the use of heated humidification. Major manufacturers, including Resmed, Respironics and Fisher & Paykel, have introduced integrated heated humidification to their CPAP systems. Respironics’ newest machine the DreamStation “analyzes ambient temperature, changing environmental conditions, relative humidity, and therapy flow to deliver optimum humidity – and ultimate comfort – throughout the night while also dramatically reducing rainout. Also, it’s adaptive, heated tube and pre-heat humidifier option help reduce rainout. With the modular design with 1 piece, dishwasher-safe water chamber makes cleanup incredibly easy.

Integrated Heated CPAP Humidifier

The integrated heated CPAP humidifier systems have become popular because of their convenience, size, and satisfaction with the results. In fact, the use of heated humidification tends to reduce or eliminate most of the disadvantages of CPAP use including dry mouth and throat and nasal congestion. The resulting outcome is a more effective treatment and a refreshed feeling on awakening. Combat “rainout” or water in the tube by properly calibrating the machine and the room temperature. Incorporate a heated tube option if available.

Manufacturers Make it Easy to Add CPAP Humidifiers and Heated Tubing

Many machines today already come with a built in humidifier, such as the ResMed AirSense 10, and the Philips DreamStation, while others, like the DeVilbiss IntelliPAP, have a removable humidifier which enables the user to choose not to use the humidifier.

IntelliPAP comes with CPAP humidification and Heated Tubing is optional However, if you find you still struggle with dryness and irritation, a heated tube added to the circuit can improve humidification efficiency. Heated tubing maintains the warm temperature of the air as it travels from the humidifier’s water chamber up to the mask. Using heated tubing can counter irritation and dryness in even the most sensitive patients. Additionally, ResMed AirMini comes with a HumidX Humidifier for integrated humidification in travel CPAP machines. 

What is HME and HumidX Portable CPAP Humidification?

The ResMed AirMini portable CPAP machine uses either HumidX or HumidX Plus. This is a small heat and moisture exchanger (HME) that provides a waterless humidification system which is effective for most climates. There is another version of this HME called HumidX Plus which is specifically designed for environments where humidity is low, or for use on an aircraft.

How does HumidX work?

The HME has tiny paper ridges that capture moisture from the breath during the exhale. On the inhale, this same heat and moisture humidify the pressurized CPAP air. The HumidX portable CPAP humidifier is disposable and can be used for up to 30 days after the package is opened. It currently works only with the AirFit N20 and AirFit P10 for the ResMedAirMini.

Can you use regular water in a CPAP humidifier?

You should not use standard tap water in a CPAP humidifier. Most tap water contains various minerals which can cause corrosion or harbor germs. When these minerals are left behind, it may then cause discoloration to the aluminum plate and plastic housing of the humidifier chamber. It may also potentially affect the longevity of the chamber. Distilled water has been purified and will not generate mineral residue upon evaporation and may extend the usable life of the chamber.

Common problems that can occur with a CPAP Humidifier

Many CPAP users ask the following questions about humidification.

How do you prevent condensation in CPAP tubing?

When warm air from a heated humidifier begins to cool as it passes through the CPAP hose, it causes condensation in the hose. Hose covers wrap around the hose to insulate it and prevent this condensation. A fairly recent option is a heated tube which helps to keep a consistent temperature within the system. Finally, changing the room temperature slightly can further help reduce this issue.

Can you stop rainout in a CPAP mask?

Rainout is condensation that feels like raindrops onto the person wearing the CPAP mask’s face. It can be disconcerting and is also sure to awaken even the soundest sleeper.

Humid air already contains a high level of water molecules. The higher the humidity in the room the more water molecules in the ambient air. The CPAP machines pull air from the room and send it through the CPAP humidifier to the patient. Even at a setting of one, the heated CPAP humidifier adds humidity to the already humid air. The combination of humid air being sent to the mask and the temperature difference inside and outside the mask combine to increase the condensation created inside the surface of the mask.

Thus, when the CPAP user moves to their back, condensation begins to fall from the mask surface onto the face. This raining sensation typically awakens the CPAP user.

Avoid condensation by either turning down the temperature of the humidifier or turning up the thermostat in your bedroom. Start by turning up the humidifier. It may be more comfortable to sleep in a cool room.

Next, dry off the inside of the mask. Turn the heated humidifier off to reduce the built-up humidity. Depending upon the weather and the room temperature, it might be best to leave the heated humidifier turned off for a couple of nights.

Can you prevent bacteria from growing in a CPAP humidifier?

Heated humidification produces molecular water vapor (.0001 microns in size) that is too small to transport bacteria into the air stream that is delivered to the patient. If small amounts of bacteria are present in the chamber, there is little risk to the patient. Bacteria require a carrier and molecular water vapor cannot provide this mechanism.

Note: The humidifier chamber does offer good conditions for colonization by microorganisms such as bacteria. This has been demonstrated over the years with other respiratory devices. This fact highlights the importance of proper and frequent cleaning of the humidifier chambers.

Can I use oils or scents in a CPAP humidifier?

A small amount of natural aromatic oil can nullify the chemical smell of your CPAP equipment. Aromatherapy can be soothing and certain oils help induce sleepiness. Use a cotton ball or diffuser with a few drops of oil near the air-intake the CPAP machine. These natural oils are not harmful to the machine. They may help some CPAP users tolerate the smell of the plastic more readily.

The use of a heated CPAP humidifier has been proven to provide a more comfortable CPAP experience. This includes higher satisfaction, fewer complications, and, ultimately, higher compliance. This translates into a more refreshed awakening and higher quality of daily life.

Cleaning the Chamber and Tubing is Important Too!

It is always important to clean your CPAP equipment. In particular, the water chamber and tubing are two of the areas which really need cleaning focus. With water and moisture in the chamber and tube, if uncleaned, it is ripe for bacteria and mildew. This can cause upper respiratory issues or extend colds longer than normal. Thus, it is important to constantly clean these accessories. Fortunately, There are easy and convenient ways to clean these products. Certainly, using a vinegar and water solution is the easiest but also can be time consuming. For people who like to set it and forget it, there are solutions such as the Lumin and SoClean2 that make CPAP cleaning a breeze.

Written by: Chris Vasta of The CPAP Shop.

Family owned and operated since 2003, we are CPAP specialists and our first priority is our customer and their satisfaction. We supply only the top manufacturers for CPAP machines and CPAP supplies. We are able to get the product you desire, answer questions you might have or make suggestions on new products. Please visit us at https://www.thecpapshop.com and become one of our thousands of satisfied customers.

Chris Vasta is the president of The CPAP Shop and an expert in sleep and respiratory therapy. He often provides insights on product design and functionality on various manufacturers’ prototypes and is frequently tapped to provide reviews on new releases.

Chris Vasta

Chris Vasta is the president of The CPAP Shop and an expert in sleep and respiratory therapy. He often provides insights on product design and functionality on various manufacturers’ prototypes and is frequently tapped to provide reviews on new releases.