AUTOMATIC RISE TIME ADJUSTMENT

• US 20110226248A1
• Filed: 11/21/2009
• Published: 09/22/2011
• Est. Priority Date: 12/09/2008
• 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: Duff, Winslow Kevin, Hill, Peter D.
• Granted Patent: US 9,913,954 B2
• Time in Patent Office: Days
• US Class Current: 128/204.23
• CPC Class Codes: A61M 16/0051 with alarm devices
• 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 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2230/432 partial CO2 pressure (P-CO2)
• CPC Class Codes: A61M 2230/50 Temperature
• CPC Class Codes: A61M 2230/60 Muscle strain, i.e. measured on the user
• CPC Class Codes: A61M 2230/65 Impedance, e.g. conductivity, capacity

Abstract

A method of providing pressure support to a patient that includes determining a measure associated with an inspiratory time of the patient during therapy, delivering a flow of breathing gas to the patient at an inspiratory positive airway pressure (IPAP) level during at least a portion of an inspiratory phase of the patient, delivering the flow of breathing gas to the patient at an expiratory positive airway pressure (EPAP) level that is less than the IPAP level during at least a portion of an expiratory phase of the patient, and automatically setting a rise time associated with a transition from the EPAP level to the IPAP level based on the measure associated with the inspiratory time of the patient. Also provided is a pressure support system adapted to perform the method.

Claims

1. A pressure support system, comprising:

a pressure generating system adapted to produce a flow of breathing gas;

a patient circuit operatively coupled to the pressure generating system to deliver the flow of breathing gas to an airway of a patient; and

a controller operatively coupled to the pressure generating system, the controller being adapted to determine a measure associated with an inspiratory time of the patient while using the pressure support system and to control the pressure generating system to;

(i) deliver the flow of breathing gas to the patient at an inspiratory positive airway pressure (IPAP) level during at least a portion of an inspiratory phase of the patient and deliver the flow of breathing gas to the patient at an expiratory positive airway pressure (EPAP) level that is less than the IPAP level during at least a portion of an expiratory phase of the patient, and (ii) automatically set a rise time associated with a transition from the EPAP level to the IPAP level based on the measure associated with the inspiratory time of the patient.

2. The pressure support system according to claim 1, further comprising a sensor operatively coupled to the controller, the sensor being adapted to measure a characteristic associated with the flow of breathing gas and to generate a signal indicative thereof, wherein the controller is adapted to receive the signal and to determine the measure associated with an inspiratory time of the patient based thereon.

3. The pressure support system according to claim 2, wherein the sensor comprises a flow sensor and the signal comprises a flow signal, or wherein the sensor comprises a pressure sensor and the signal comprises a pressure signal.

4. The pressure support system according to claim 1, wherein the measure associated with the inspiratory time of the patient is an average inspiratory time of the patient determined over (a) a predetermined number of respiratory cycles, or (b) a predetermined time period.

5. The pressure support system according to claim 1, wherein the measure associated with the inspiratory time of the patient is an inspiratory time of the patient associated with a particular respiratory cycle.

6. The pressure support system according to claim 1, wherein the controller is adapted to automatically set a rise time associated with a transition from the EPAP level to the IPAP level based on the measure associated with the inspiratory time of the patient by (a) multiplying the measure associated with the inspiratory time of the patient by a predetermined constant to determine the rise time, or (b) consulting a stored look-up table using the measure associated with the inspiratory time of the patient to determine the rise time.

7. The pressure support system according to claim 1, wherein the controller is adapted to determine a measure associated with a total breath time of the patient while using the pressure support system and to automatically set the rise time associated with the transition from the EPAP level to the IPAP level based on both the measure associated with the inspiratory time of the patient and the measure associated with a total breath time of the patient.

8. The pressure support system according to claim 7, wherein the measure associated with the inspiratory time of the patient is an average inspiratory time of the patient and wherein the measure associated with a total breath time of the patient is an average total breath time of the patient.

9. The pressure support system according to claim 7, wherein the measure associated with the inspiratory time of the patient is an inspiratory time of the patient associated with a particular respiratory cycle and wherein the measure associated with a total breath time of the patient is a total breath time of the patient associated with the particular respiratory cycle.

10. The pressure support system according to claim 7, wherein the controller is adapted to automatically set a rise time associated with a transition from the EPAP level to the IPAP level based on both the measure associated with the inspiratory time of the patient and the measure associated with a total breath time of the patient by consulting a stored look-up table using both the measure associated with the inspiratory time of the patient and the measure associated with a total breath time of the patient to determine the rise time.

11. The pressure support system according to claim 1, wherein the transition from the EPAP level to the IPAP level is (a) an exponential ramp having a variable slope, or (b) a straight line ramp having a constant slope.

12. A method of providing pressure support to a patient, comprising:

determining a measure associated with an inspiratory time of the patient during therapy;

delivering a flow of breathing gas to the patient at an inspiratory positive airway pressure (IPAP) level during at least a portion of an inspiratory phase of the patient;

delivering the flow of breathing gas to the patient at an expiratory positive airway pressure (EPAP) level that is less than the IPAP level during at least a portion of an expiratory phase of the patient; and

automatically setting a rise time associated with a transition from the EPAP level to the IPAP level based on the measure associated with the inspiratory time of the patient.

13. The method according to claim 12, wherein the measure associated with the inspiratory time of the patient is an average inspiratory time of the patient determined over (a) a predetermined number of respiratory cycles, or (b) a predetermined time period.

14. The method according to claim 12, wherein the measure associated with the inspiratory time of the patient is an inspiratory time of the patient associated with a particular respiratory cycle.

15. The method according to claim 12, wherein the automatically setting comprises (a) multiplying the measure associated with the inspiratory time of the patient by a predetermined constant to determine the rise time, or (b) consulting a stored look-up table using the measure associated with the inspiratory time of the patient to determine the rise time.

16. The method according to claim 12, further comprising determining a measure associated with a total breath time of the patient while using the pressure support system, wherein the automatically setting comprises automatically setting the rise time associated with the transition from the EPAP level to the IPAP level based on both the measure associated with the inspiratory time of the patient and the measure associated with a total breath time of the patient.

17. The method according to claim 16, wherein the measure associated with the inspiratory time of the patient is an average inspiratory time of the patient and wherein the measure associated with a total breath time of the patient is an average total breath time of the patient.

18. The method according to claim 16, wherein the measure associated with the inspiratory time of the patient is an inspiratory time of the patient associated with a particular respiratory cycle and wherein the measure associated with a total breath time of the patient is a total breath time of the patient associated with the particular respiratory cycle.

19. The method according to claim 16, wherein the automatically setting comprises consulting a stored look-up table using both the measure associated with the inspiratory time of the patient and the measure associated with a total breath time of the patient to determine the rise time.