A new hygroscopic condenser humidifier.

A new hygroscopic condenser humidifier for the mechanically ventilated patient has been tested. It functions as a heat and moisture exchange device (HME) with an additional hygroscopic sponge to minimize the water loss from the breathing circuit. A comparative in vitro study was undertaken with a conventional HME. The influence of tidal volume, inspiratory flow rate and minute volume on the relative humidity of the inspiratory gas and on the water loss was investigated. The new device provides adequate humidification within a broad scale of ventilatory settings. In a subsequent clinical test the hygroscopic condenser humidifier proved to be a simple and reliable way of humidification.