Patent ID: 6363930
Filing Date: 2002-04-02
Classification: A61M

Abstract:
An apparatus for heating and humidifying respiratory gases comprising:a housing having a first port adapted for connection to a tracheal tube device and a second port adapted for connection to a tube for passing respiratory gases to and from the housing, the first port and the second port being positioned so that respiratory gases passing to and from the housing pass therebetween; a gas permeable member positioned in the housing between the first port and the second port and having a size and structure suitable to exchange effective amounts of heat and moisture with respiratory gases passing to and from the housing; and a generating material located in the housing between the first port and the second port and being present in an amount effective to generate water available to humidify respiratory gases passing through the housing, the generating material being positioned in the housing as a layer of non-uniform thickness across substantially the entire flow path of respiratory gases passing through the housing from the first port to the second port, wherein the layer of non-uniform thickness includes a peripheral region having a first thickness, and a central region having a second thickness which is greater than the first thickness, so as to prolong the time the generating material is used to generate water available to humidify respiratory gases relative to an identical generating material present in a similar apparatus in an amount equal to the amount of the generating material and positioned as a layer of uniform thickness across substantially the entire flow path of respiratory gases passing through the housing from the second port.