Humidifier for respiratory apparatus

Abstract

A flexible tape heater ( 110 ) in a patient conduit ( 112 ) may be used to heat the flow of gas in the patient conduit ( 112 ) that is delivered to the patient mask ( 116 ). The thin, flat and extended nature of the flexible tape heater ( 110 ) may enhance heat transfer with the gas flow whilst also providing low impedance to the gas flow. Heating of the gas may facilitate the desired temperature and humidity to be reached for the gas delivered to the patient by the respiratory apparatus. The flexible tape heater ( 110 ) may be placed in the patient conduit ( 112 ) such that the flexible tape heater ( 110 ) is twisted or bent about one or more of the flexible tape heater's ( 110 ) three axes. Additionally these configurations may be used to enhance the turbulent mixing of the water vapour produced in the humidification chamber ( 114 ) with the gas flow.

1 . A respiratory apparatus for delivering gas to a patient, including:
 a PAP device generating a supply of pressurised gas to be delivered to the patient;   a humidifier for vaporizing water and delivering water vapour to humidify the gas;   a gas flow path leading from the PAP device to the humidifier and from the humidifier to a patient interface; and a heater in thermal contact with one or more of the gas and the water, wherein the heater comprises an elongate heating filament in the form of a tape.   
     
     
         2 . A respiratory apparatus according to  claim 1  wherein the gas flow path includes a first portion between the PAP device and the humidifier and a second portion between the humidifier and the patient interface, and wherein the heating filament extends along at least part of both said first and second portions of the gas flow path. 
     
     
         3 . A respiratory apparatus according to  claim 1  wherein said heating filament is in thermal contact with both the gas in the gas flow path and the water in the humidifier. 
     
     
         4 . A respiratory apparatus according to  claim 1  wherein the heating filament has an intermediate portion which is in contact with the water in the humidifier. 
     
     
         5 - 39 . (canceled) 
     
     
         40 . A humidifier for respiratory apparatus, comprising:
 a first respiratory gas passage for receiving gas from a PAP device;   a humidification chamber adapted to contain water for vaporization;   a second respiratory gas passage for delivering humidified gas from the humidification chamber to a patient interface; and   and a heater in thermal contact with one or more of the gas and the water, wherein the heater comprises an elongate heating filament in the form of a tape.   
     
     
         41 . A humidifier according to  claim 40 , wherein the heating filament extends along at least part of both said first and second respiratory gas passages. 
     
     
         42 . A humidifier according to  claim 40 , wherein the heating filament is in thermal contact with the water in the humidification chamber. 
     
     
         43 . A respiratory apparatus for delivering gas to a patient, including:
 a PAP device generating a supply of pressurised gas to be delivered to the patient;   a gas flow path leading from the PAP device to a patient interface; and a heater in thermal contact with the gas within the gas flow path, wherein the heater comprises an elongate heating filament in the form of a tape.   
     
     
         44 - 46 . (canceled) 
     
     
         47 . A respiratory apparatus for delivering gas to a patient, including:
 a PAP device generating a supply of pressurised gas to be delivered to the patient;   a gas flow path leading from the PAP device to a patient interface; and one or more sensors or control elements for sensing or controlling properties of the gas,   wherein the sensors or control elements are located along an elongate filament in the form of a tape in contact with the gas in the gas flow path.   
     
     
         48 . A humidifier for respiratory apparatus, comprising a container for holding a body of water, apparatus for passing a respiratory gas flow over the surface of the water to humidify the gas flow, and a heater supported so as to preferentially heat the water adjacent said surface. 
     
     
         49 . A humidifier according to  claim 48 , wherein the heater is supported so as to float adjacent the surface of the water. 
     
     
         50 . A humidifier according to  claim 49 , wherein the heater is supported by an inherent buoyancy of the heater. 
     
     
         51 . A humidifier according to  claim 49 , wherein the heater is supported by a buoyant support body. 
     
     
         52 - 62 . (canceled) 
     
     
         63 . A humidifier for respiratory apparatus, comprising a first respiratory gas passage for receiving gas from a PAP device, a humidification chamber, a second respiratory gas passage for delivering humidified gas from the humidification chamber to a patient interface, and a heater in thermal contact with one or more of the gas and the water, wherein the heater comprises an elongate heating filament extending along at least part of both said first and second respiratory gas passages. 
     
     
         64 . A humidifier according to  claim 63 , wherein the heating filament is in thermal contact with water in the humidifier chamber. 
     
     
         65 . A humidifier according to  claim 63 , wherein the heating filament comprises two or more separately controllable heating zones within the respiratory apparatus. 
     
     
         66 . (canceled) 
     
     
         67 . (canceled) 
     
     
         68 . A respiratory apparatus for delivering gas to a patient, including: a PAP device generating a supply of pressurised gas to be delivered to the patient;
 a humidifier for vaporizing water and delivering water vapour to humidify the gas;   a gas flow path leading from the PAP device to the humidifier and from the humidifier to a patient interface; and   a heater in thermal contact with one or more of the gas and the water, wherein the heater comprises two or more controllable heating zones within the respiratory apparatus.   
     
     
         69 . A method of controlling one or more characteristics of a gas being delivered by a respiratory apparatus to a patient, including the steps of:
 providing a humidifier apparatus containing water;   providing a heater in contact with one or more of the gas being provided to the patient and the water in the humidifier apparatus, said heater having two or more controllable heater zones; and controlling the heater zones to control the one or more characteristics of the gas within the different zones of the respiratory apparatus to provide gas to the patent with the desired one or more characteristics.   
     
     
         70 . A respiratory apparatus according to  claim 69 , wherein said one or more characteristics includes one or more of temperature, humidity, gas flow, gas velocity or pressure. 
     
     
         71 . A method of increasing patient comfort during start-up humidification of a gas being delivered by a respiratory apparatus to a patient, including the steps of:
 providing a heater, in contact with a gas being provided to the patient along a gas flow path and in contact with water in a humidifier apparatus; and   commencing heating of the gas in the gas flow path and heating of the water in the humidification apparatus, such that the patient is initially provided with heated gas while the temperature of the water in the humidification apparatus is being increased to the operating temperature.   
     
     
         72 . (canceled) 
     
     
         73 . (canceled)