Humidification In CPAP Therapy

The following information is provided by Fisher & Paykel Healthcare

What is Humidity?

Humidity is the amount of water vapor in a gas. When discussing humidity, we can refer to either relative humidity or absolute humidity:

Absolute Humidity (AH) is the amount of water vapor per liter of gas, measured in mg/L.	Relative Humidity (RH) is a measure of how much water vapor is in the gas compared to its capacity to hold water vapor. It is measured as a percentage (%).

A. If a liter of gas can hold 44mg of water vapor and it contains 44mg, then it has 100% Relative Humidity (or it is saturated). B. If the same liter of gas contains only 22mg of water vapor, then it would only be half full or has 50% Relative Humidity.

Maximum Capacity is The maximum amount of water vapor a gas can hold is determined by temperature.

Humidification and CPAP

The graph above shows that heated humidification provides far greater humidity than both room air and cold passover humidification.

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• The Role Of Humidification in CPAP Therapy
• What is Humidity?
• How the Human Body Humidifies Air
• CPAP Therapy Potential Problems
• Mouth leak and the Vicious Cycle
• Increase in Nasal Resistance
• Compliance With CPAP Therapy
• Frequently Asked Questions
• References