AUTOMATIC HUMIDITY CONTROL IN A PRESSURE SUPPORT SYSTEM

• US 20130087143A1
• Filed: 04/27/2011
• Published: 04/11/2013
• Est. Priority Date: 06/04/2010
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Pujol, John Raymond
• Granted Patent: US 10,046,136 B2
• Time in Patent Office: Days
• US Class Current: 128/203.12
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/16 Devices to humidify the respiration air A61M16/1045 takes precedence
• CPC Class Codes: A61M 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/3368 Temperature

Abstract

A method of automatically controlling the humidity of a gas stream of a pressure support system (50) during use of the system is provided. The method includes receiving a first humidification level, and controlling operation of a humidifier (68) based on the first humidification level and at least one of: (i) one or more environmental parameters relating to environmental conditions around the pressure support system, (ii) one or more gas stream parameters relating to a gas stream output by the pressure support system to a patient circuit (56, 58), (iii) one or more respiratory demand parameters of a user of the pressure support system, and (iv) one or more operating parameters of the pressure support system that effect a flow rate that is generated by a pressure generating system (52, 60) of the pressure support system.

Claims

1. A method of automatically controlling a humidity of a gas stream of a pressure support system during use of the pressure support system by a user, comprising:

receiving a first humidification level; and

controlling operation of a humidifier of the pressure support system based on the first humidification level and one or more parameters indicating the user'"'"'s actual demand for respiratory gas during a breath.

2. The method according to claim 1, wherein the controlling includes:

determining a second humidification level based on the first humidification level and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas; and

controlling operation of the humidifier based on the second humidification level, wherein the second humidification level is a level determined to cause a humidity of a breathing gas delivered to the patient through the patient circuit to be substantially equal to the first humidification level.

4. The method according to claim 1, further comprising determining one or more environmental parameters relating to environmental conditions around the pressure support system, one or more gas stream parameters relating to a gas stream output by the pressure support system to a patient circuit, and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, wherein the controlling operation of the humidifier is based on the first humidification level and the one or more environmental parameters, the one or more gas stream parameters, the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, and one or more operating parameters of the pressure support system that affect a flow rate that is generated by a pressure generating system of the pressure support system.

5. The method according to claim 4, wherein determining the one or more environmental parameters, the one or more gas stream parameters, and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas comprises measuring or estimating the one or more environmental parameters, the one or more gas stream parameters, and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas.

7. The method according to claim 1, further comprising determining the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, wherein the controlling operation of the humidifier is based on the first humidification level, the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, and one or more operating parameters of the pressure support system that affect a flow rate that is generated by a pressure generating system of the pressure support system.

8. The method according to claim 4, wherein the one or more environmental parameters are selected from the group consisting of ambient temperature and ambient humidity, wherein the one or more gas stream parameters are selected from the group consisting of gas temperature and gas humidity, and wherein the one or more operating parameters include a pressure level of a gas within the pressure support system.

10. The method according to claim 1, wherein the one or more parameters indicating the user'"'"'s actual demand for respiratory gas is at least one of tidal volume of the user during the breath and respiratory rate of the user during the breath.

23. The method according to claim 1, wherein the controlling the operation of the humidifier of the pressure support system is further based on at least one of one or more environmental parameters relating to environmental conditions around the pressure support system and one or more gas stream parameters relating to a gas stream output by the pressure support system to a patient circuit.

3. (canceled)

6. (canceled)

9. (canceled)

11. (canceled)

12. A pressure support system, comprising:

a pressure generating system structured to generate a pressurized gas stream;

a humidifier structured to humidify the pressurized gas stream;

a patient circuit operatively coupled to the humidifier; and

a controllers operatively coupled to the pressure generating system and the humidifier, the controller being adapted to control a humidity of a humidified gas stream output by the humidifier by

receiving a first humidification level, and

controlling operation of the humidifier based on the first humidification level and one or more parameters indicating a user'"'"'s actual demand for respiratory gas during a breath

13. The pressure support system according to claim 12, wherein the controller further controls the humidity of a humidified gas stream output by the humidifier by:

determining a second humidification level based on the first humidification level and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas; and

controlling operation of the humidifier based on the second humidification level, wherein the second humidification level is a level determined to cause a humidity of a breathing gas delivered to the patient through the patient circuit to be substantially equal to the first humidification level.

15. The pressure support system according to claim 12, wherein the controller is further adapted to determine one or more environmental parameters relating to environmental conditions around the pressure support system, one or more gas stream parameters relating to a gas stream output by the pressure support system to a patient circuit, and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, wherein the controlling operation of the humidifier is further based on the one or more environmental parameters, the one or more gas stream parameters, and one or more operating parameters of the pressure support system that affect a flow rate that is generated by a pressure generating system of the pressure support system.

16. The pressure support system according to claim 15, wherein the one or more environmental parameters, the one or more gas stream parameters, and the one or more parameters indicating the user'"'"'s actual demand for respiratory gas are either measured using one or more sensors or estimated by the controller.

17. The pressure support system according to claim 12, wherein the controller is further adapted to determine the one or more parameters indicating the user'"'"'s actual demand for respiratory gas.

18. The pressure support system according to claim 12, wherein the controller is further adapted to determine the one or more parameters indicating the user'"'"'s actual demand for respiratory gas, and wherein the controlling operation of the humidifier is based on the first humidification level, the one or more respiratory demand parameters, and one or more operating parameters of the pressure support system that affect a flow rate that is generated by a pressure generating system of the pressure support system.

19. The pressure support system according to claim 15, wherein the one or more environmental parameters are selected from the group consisting of ambient temperature and ambient humidity, and wherein the one or more gas stream parameters are selected from the group consisting of gas temperature and gas humidity.

21. The pressure support system according to claim 12, wherein the one or more parameters indicating the user'"'"'s actual demand for respiratory gas is at least one of tidal volume of the user during the breath and respiratory rate of the user during the breath.

22. The pressure support system according to claim 15, wherein the one or more operating parameters include a pressure level of a gas within the pressure support system.

24. The pressure support system according to claim 12, wherein the controlling the operation of the humidifier of the pressure support system is further based on at least one of one or more environmental parameters relating to environmental conditions around the pressure support system one or more gas stream parameters relating to a gas stream output by the pressure support system to a patient circuit.

14. (canceled)

20. (canceled)