Deterministically controlled humidification system

Abstract

A respiratory humidification system for providing humidification to gases that pass through a gas passage way before being provided to an airway of a patient is disclosed. The respiratory humidification system may include a liquid flow controller providing a controlled flow of liquid, a heating system including a heating surface configured to be located in a gases passage way and provide humidification to gases passing through the passage way, wherein the heating system receives the controlled flow of liquid, and one or more hardware processors providing deterministic control of a humidity level of gases passing through the gas passage way by instructing the liquid flow controller to adjust the controlled flow of liquid received at the heating system.

What is claimed is: 
     
         1 . A respiratory humidification system for providing heated and humidified respiratory gases to a patient, the respiratory humidification system comprising:
 a liquid flow controller providing a controlled flow of liquid;   a heating system including a heating surface configured to receive the controlled flow of liquid and provide humidification to gases passing through the humidification system;   one or more temperature sensors measuring a surface temperature of the heating surface;   one or more hardware processors providing deterministic control of a humidity level of gases passing through the respiratory humidification system by instructing the liquid flow controller to adjust the controlled flow of liquid received at the heating system and instructing the heating system to adjust the surface temperature of the heating surface, wherein adjusting the surface temperature of the heating surface provides control to produce a known evaporative area; and   one or more sensors configured to detect whether the heating surface is wetted in at least one region.   
     
     
         2 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are liquid sensors. 
     
     
         3 . The respiratory humidification system of  claim 1 , wherein the one or more sensors comprise at least two liquid sensors configured to detect whether the heating surface is wetted at two or more regions of the heating surface. 
     
     
         4 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are located at, on, adjacent, or proximal the heating surface. 
     
     
         5 . The respiratory humidification system of  claim 1 , wherein the liquid flow controller comprises a metering system. 
     
     
         6 . The respiratory humidification system of  claim 1 , wherein the liquid flow controller is a pump in an open loop configuration. 
     
     
         7 . The respiratory humidification system of  claim 1 , wherein the liquid flow controller is a pump or flow actuator in series with a flow sensor in a closed loop configuration. 
     
     
         8 . The respiratory humidification system of  claim 2 , further comprising at least one temperature sensor forming part of the heating system. 
     
     
         9 . The respiratory humidification system of  claim 8 , wherein the at least one temperature sensor is utilized to determine a proportion of the heating surface that is saturated with a liquid. 
     
     
         10 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are used to prevent overflow of liquid onto the heating surface. 
     
     
         11 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are used by the one or more hardware processors to adjust the deterministic control of the humidity level of gases passing through the respiratory system. 
     
     
         12 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are used by the one or more hardware processors to adjust the evaporative area of the heating surface. 
     
     
         13 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are temperature sensors. 
     
     
         14 . The respiratory humidification system of  claim 13 , wherein at least one temperature sensor is utilized to determine a proportion of the heating surface that is saturated with a liquid. 
     
     
         15 . The respiratory humidification system of  claim 1 , wherein the one or more sensors are resistive or capacitive sensors. 
     
     
         16 . The respiratory humidification system of  claim 1 , wherein the heating system comprises a printed circuit board (PCB) or etched foil over-molded with a surface comprising micro-channels to form the heating surface. 
     
     
         17 . The respiratory humidification system of  claim 16 , wherein the surface has micro-channels that extend in only a single direction. 
     
     
         18 . The respiratory humidification system of  claim 16 , wherein the micro-channels include a first set of distribution channels connected to a second set of main channels. 
     
     
         19 . The respiratory humidification system of  claim 18 , wherein the number of distribution channels is less than the number of main channels. 
     
     
         20 . The respiratory humidification system of  claim 16 , wherein the micro-channels are distributed radially from a single point. 
     
     
         21 . A respiratory humidification system for providing heated and humidified respiratory gases to a patient, the respiratory humidification system comprising:
 a liquid flow controller providing a controlled flow of liquid;   a heating system including a heating surface configured to receive the controlled flow of liquid and provide humidification to gases passing through the humidification system;   one or more temperature sensors measuring a surface temperature of the heating surface;   one or more hardware processors providing deterministic control of a humidity level of gases passing through the respiratory humidification system by instructing the liquid flow controller to adjust the controlled flow of liquid received at the heating system and instructing the heating system to adjust the surface temperature of the heating surface, wherein adjusting the surface temperature of the heating surface provides control to produce a known evaporative area; and   one or more sensors configured to detect whether the heating surface is wetted in at least one region, wherein the one or more sensors comprise at least one temperature sensor, wherein the at least one temperature sensor is utilized to determine a proportion of the heating surface that is saturated with a liquid.   
     
     
         22 . A respiratory humidification system for providing heated and humidified respiratory gases to a patient, the respiratory humidification system comprising:
 a liquid flow controller providing a controlled flow of liquid;   a heating system including a heating surface configured to receive the controlled flow of liquid and provide humidification to gases passing through the humidification system;   one or more temperature sensors measuring a surface temperature of the heating surface;   one or more hardware processors providing deterministic control of a humidity level of gases passing through the respiratory humidification system by instructing the liquid flow controller to adjust the controlled flow of liquid received at the heating system and instructing the heating system to adjust the surface temperature of the heating surface, wherein adjusting the surface temperature of the heating surface provides control to produce a known evaporative area;   one or more sensors configured to detect whether the heating surface is wetted in at least one region, wherein the one or more sensors comprise at least two liquid sensors configured to detect whether the heating surface is wetted at two or more regions of the heating surface, wherein the one or more sensors are used by the one or more hardware processors to adjust the evaporative area of the heating surface; and   at least one temperature sensor.