System and method for controlling airway gas parameters during high frequency positive pressure ventilation

Patent metadata

Field	Value
Publication number	US-10252012-B2
Application number	US-201414655767-A
Country	US
Kind code	B2
Filing date	Jan 9, 2014
Priority date	Jan 17, 2013
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

The present disclosure pertains to a high frequency positive pressure ventilation system. The system may be configured to maintain a time-averaged airway pressure level at a target time-averaged airway pressure level and/or a peak-to-peak pressure difference at a target peak-to-peak pressure difference. In some embodiments, the system is configured to control the inspiratory subsystem, the expiratory flow generator and exhalation valve in accordance with a high frequency positive pressure ventilation therapy regime.

First claim

What is claimed is:

1. A high frequency positive pressure ventilation system, the system comprising:
an inspiratory subsystem to generate a pressurized flow of breathable gas for delivery to the airway of the subject;
an expiratory flow generator configured to draw gas from the airway of a subject to a system outlet during an exhalation;
one or more sensors configured to generate output signals conveying information related to one or more gas parameters at or near the airway of the subject;
an exhalation valve configured to selectively control flow from the airway of the subject though the expiratory flow generator;
one or more processors configured to execute computer program modules, the computer program modules comprising:
a parameter module configured to determine the one or more gas parameters at or near the airway of the subject based on the output signals, the parameter module configured to determine a time averaged airway pressure level;
a target module configured to obtain target values for the one or more gas parameters, the target module configured to obtain a target time averaged airway pressure level; and
a control module configured to control the inspiratory subsystem, the expiratory flow generator and the exhalation valve to maintain the time averaged airway pressure level at the target time averaged airway pressure level over a series of high frequency pressure cycles,
the control module further configured to control the time averaged airway pressure level during the exhalation with the expiratory flow generator and to facilitate a rate of change in the airway pressure during the exhalation with the exhalation valve, and further wherein the control module is configured to control the exhalation valve to open partially to facilitate faster changes in the airway pressure during the exhalation.

2. The system of claim 1 , wherein the parameter module is further configured to determine a peak-to-peak pressure difference over the series of high frequency pressure cycles based on the output signals;
wherein the target module is further configured to obtain a target peak-to-peak pressure difference; and
wherein the control module is further configured to selectively control the inspiratory subsystem, the expiratory flow generator and the exhalation valve to maintain the peak-to-peak pressure difference at the target peak-to-peak pressure difference over the series of high frequency pressure cycles.

3. The system of claim 2 , wherein the parameter module is configured such that the peak-to-peak pressure difference is related to a difference between two or more consecutive maximum pressures.

4. The system of claim 1 , wherein the control module is configured to control the inspiratory subsystem, the expiratory flow generator and the exhalation valve to deliver the positive pressure ventilation at a frequency between about 3 Hz and about 25 Hz.

5. The system of claim 1 , wherein the control module is configured to control the inspiratory subsystem, the expiratory flow generator and the exhalation valve such that a tidal volume of the pressurized flow of breathable gas is about 6 mi/kg.

6. A method of operating a high frequency positive pressure ventilation system for delivering high frequency positive pressure ventilation to a subject, the system comprising an inspiratory subsystem, an expiratory flow generator, one or more sensors, an exhalation valve, and one or more processors, the one or more processors configured to execute computer program modules, the computer program modules comprising a parameter module, a target module, and a control module, the method comprising:
generating a pressurized flow of breathable gas for delivery to the airway of the subject with the inspiratory subsystem;
drawing gas from the airway of the subject to a system outlet with the expiratory flow generator;
generating output signals conveying information related to one or more gas parameters at or near the airway of the subject with the one or more sensors;
selectively controlling, with the inspiratory subsystem, the exhalation valve, the flow of gas drawn from the airway of the subject by the expiratory flow generator;
determining the one or more gas parameters at or near the airway of the subject based on the output signals with the parameter module, the one or more gas parameters including a time averaged airway pressure level;
obtaining target values for the one or more gas parameters with the target module, the target values including a target time averaged airway pressure level;
controlling the inspiratory subsystem, the expiratory flow generator and the exhalation valve with the control module to deliver a series of pressure cycles in accordance with a high frequency positive pressure ventilation therapy regime; and
selectively controlling the inspiratory subsystem, the exhalation valve and the expiratory flow generator with the control module to maintain the time averaged airway pressure level at the target time averaged airway pressure level over the series of pressure cycles, wherein the selectively controlling step further comprises controlling the airway pressure during the drawing step with the expiratory flow generator, controlling a rate of change in the airway pressure during the drawing step with the exhalation valve, and controlling the exhalation valve to open partially to facilitate faster changes in the airway pressure during the exhalation.

7. The method of claim 6 , further comprising:
determining a peak-to-peak pressure difference over the series of pressure cycles based on the output signals with the parameter module;
obtaining a target peak-to-peak pressure difference with the target module; and
selectively controlling the inspiratory subsystem, the exhalation valve and the expiratory flow generator with the control module to maintain the peak-to-peak pressure difference at the target peak-to-peak pressure difference over the series pressure cycles.

8. The method of claim 7 , wherein the peak-to-peak pressure difference is related to a difference between two or more consecutive maximum pressures.

9. The method of claim 6 , wherein the series of pressure cycles have a frequency between about 3Hz and about 25Hz.

10. The method of claim 6 . further comprising controlling the inspiratory subsystem, the expiratory flow generator and the one or more valves such that a tidal volume of the pressurized flow of breathable gas is about 6 ml/kg.

11. A high frequency positive pressure ventilation system, the system comprising:
means for generating a pressurized flow of breathable gas for delivery to the airway of the a subject;
means for drawing gas out of the airway of the subject during an exhalation;
means for generating output signals conveying information related to one or more gas parameters at or near the airway of the subject;
means for regulating a rate at which gas is drawn out of the airway of the subject;
means for determining the one or more gas parameters at or near the airway of the subject, the means for determining the one or more gas parameters configured to determine a time averaged airway pressure level;
means for obtaining target values for the one or more gas parameters, the means for obtaining target values configured to obtain a target time averaged airway pressure level; and
means for controlling the means for generating, the means for drawing and the means for regulating to deliver a series of pressure cycles in accordance with a high frequency positive pressure ventilation therapy regime such that the time averaged airway pressure level is maintained at the time averaged airway pressure level at the target time averaged airway pressure level ov

Assignees

• Koninklijke Philips Nv

Inventors

• Garde Smita
• Ahmad Samir

Classifications

• A61M16/208

  Non-controlled one-way valves, e.g. exhalation, check, pop-off non-rebreathing valves · CPC title

• A61M2205/3334

  Measuring or controlling the flow rate · CPC title

• A61M16/0003 Primary

  Accessories therefor, e.g. sensors, vibrators, negative pressure · CPC title

• A61M2016/003

  with a flowmeter · CPC title

• A61M16/20

  Valves specially adapted to medical respiratory devices · CPC title