METHOD AND APPARATUS FOR SUBSTANCE DELIVERY IN SYSTEM FOR SUPPLYING BREATHABLE GAS

• US 20100282251A1
• Filed: 07/16/2010
• Published: 11/11/2010
• Est. Priority Date: 12/12/1996
• Status: Active Grant

• Current Assignee: Resmed Limited (ResMed Incorporated)
• Original Assignee: Resmed Limited (ResMed Incorporated)
• Inventors: Yerbury, Victor, CALLUAUD, Michel
• Granted Patent: US 8,397,716 B2
• Time in Patent Office: Days
• US Class Current: 128/200.23
• CPC Class Codes: A61M 15/0065 Inhalators with dosage or measuring devices A61M15/0028 takes precedence; dosage devices incorporated in aerosol cans B65D83/52
• CPC Class Codes: A61M 15/0066 with means for varying the dose size
• CPC Class Codes: A61M 16/14 by mixing different fluids, one of them being in a liquid phase
• CPC Class Codes: A61M 16/147 the respiratory gas not passing through the liquid container
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit

Abstract

A substance delivery apparatus for use with a system for supplying breathable gas to a human or animal includes a sensor to measure the pressure of the supplied breathable gas and to detect inhalation by the human or animal; and a reservoir, a conduit, a pump, and a diaphragm to deliver the substance to the human or animal during inhalation at a pressure higher than the supplied pressure of the breathable gas.

Claims

1. A substance delivery apparatus for supplying a substance to a human or animal, the substance delivery apparatus comprising:

means for generating a flow of pressurized breathable gas;

means for measuring the pressure of the flow of pressurized breathable gas; and

means for delivering the substance with the flow of pressurized breathable gas to the human or animal only during inhalation at a pressure that exceeds the measured pressure of the flow of pressurized breathable gas by a predetermined pressure difference.

2. An apparatus as claimed in claim 1, further comprising means for detecting inhalation by the human or animal.

3. An apparatus as claimed in claim 1, wherein the substance is a medicinal substance in the form of a gas, mist, aerated suspension, jet, spray, or a gas mixture.

4. An apparatus as claimed in claim 1, wherein the means for delivering the substance is adapted to deliver the substance to a respiratory system of the human or animal.

5. An apparatus as claimed in claim 4, wherein the means for delivering the substance is adapted to deliver the substance to nasal airways of the human or animal.

6. An apparatus as claimed in claim 2, wherein the means for detecting inhalation comprises an airflow sensor adapted to measure a volumetric flow rate of the flow of pressurized breathable gas passing through a flexible conduit in fluid communication with the means for generating the flow of pressurized breathable gas and a mask adapted to be worn by the human or animal and being adapted to generate a first input signal indicative of the breathable gas flow rate.

7. An apparatus as claimed in claim 6, further comprising a differentiating filter to derive the first signal into a second input signal indicative of acceleration or deceleration of the breathable gas to thereby indicate inhalation or exhalation respectively.

8. An apparatus as claimed in claim 1, further including means for measuring a volume of the substance to be delivered to the human or animal.

9. An apparatus as claimed in claim 1, wherein the means for measuring the pressure is a pressure transducer adapted to be connected to a conduit in fluid communication with the means for generating a flow of pressurized breathable gas and a patient interface adapted to be worn by the human or animal.

10. An apparatus as claimed in claim 1, wherein the means for delivering a substance is a positive displacement pump.

11. An apparatus as claimed in claim 10, wherein the positive displacement pump is a diaphragm pump.

12. An apparatus as claimed in claim 11, wherein the diaphragm pump is in fluid communication with a substance reservoir via a one-way valve adapted to allow the substance to only pass from the reservoir to the diaphragm pump.

13. An apparatus as claimed in claim 11, wherein the diaphragm pump is displaced by a linear drive.

14. An apparatus as claimed in claim 13, wherein the linear drive is an electromagnet.

15. An apparatus as claimed in claim 11, wherein a diaphragm of the diaphragm pump is displaced by a rotary to linear converter driven by a rotary drive.

16. An apparatus as claimed in claim 15, wherein the rotary drive is one of an electric DC motor, an electric AC motor, a stepper motor or a brushless motor.

17. A method of delivering a substance to a human or animal, the method comprising:

generating a flow of pressurized breathable gas;

measuring the pressure of the flow of pressurized breathable gas; and

delivering a substance to the human or animal with the flow of pressurized breathable gas only during inhalation at a pressure that exceeds the pressure of the pressurized flow of breathable gas by a predetermined pressure difference.

18. A method as claimed in claim 17, wherein the substance is a medicinal substance in the form of a gas, mist, aerated suspension, jet, spray, or a gas mixture.

19. A method as claimed in claim 17, wherein the substance is delivered to a respiratory system of the human or animal.

20. A method as claimed in claim 17, further comprising:

measuring the volumetric flow rate of the breathable gas with an airflow sensor;

generating a first input signal indicative of the breathable gas flow rate; and

differentiating the first signal into a second signal indicative of breathable gas acceleration or deceleration to indicate inhalation or exhalation respectively.