Method and apparatus for providing and controlling oxygen supply

• US 20020195105A1
• Filed: 09/04/2002
• Published: 12/26/2002
• Est. Priority Date: 01/13/2000
• Status: Abandoned Application

• Current Assignee: Brent Blue, Steven Stokes
• Original Assignee: Brent Blue, Steven Stokes
• Inventors: Blue, Brent, Stokes, Steven
• Application Number:
  US10/235,472
• Publication Number:
  US 20020195105A1
• Time in Patent Office: Days
• US Class Current: 128/204.21
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/0677 Gas-saving devices therefor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2230/205 partial oxygen pressure (P-O2)

Abstract

A method and apparatus for controlling oxygen delivery is disclosed. An oxygen delivery control apparatus comprises a valve for controlling an oxygen flow from an oxygen supply to a delivery apparatus, a pressure sensor for detecting a period of inhalation by the user, an oximeter arranged to measure a blood-oxygen saturation level of a user, a flow sensor for measuring the flow rate of oxygen, and a processor for controlling the valve to permit oxygen to flow when the output signal from the oximeter indicates a blood-oxygen saturation which is below a selected blood-oxygen saturation level and a condition of inhalation is detected. The processor utilizes flow rate data to calculate average flow and changes in average flow, and sounds an alarm in the event changes in average flow exceed a predetermined amount. The invention includes one or more methods and control strategies for delivering the oxygen to the user.

Claims

1. A portable oxygen delivery control apparatus for controlling a flow of oxygen to a user in an open-loop breathing system including an oxygen supply and a delivery apparatus for delivering supplemental oxygen to a user comprising:

an oximeter arranged to measure a blood-oxygen saturation level of a user and provide an output signal indicative of said blood-oxygen saturation level;

a valve, a first port of said valve adapted to be connected to said oxygen supply and a second port adapted to be connected to said delivery apparatus, said valve having a first position permitting oxygen to flow from said supply to said delivery apparatus, and a second position preventing oxygen from flowing from said supply to said delivery apparatus;

a pressure sensor, said sensor associated with a said valve, said sensor including a diaphragm exposed to the atmosphere on opposing sides so as to be altitude correcting and arranged to detect a period of inhalation by said user by detecting a condition of reduced pressure associated with said delivery apparatus for delivering supplemental oxygen to a user when said valve is in said second position;

a selector adapted to accept a target blood-oxygen saturation level;

a flow sensor, said flow sensor positioned along a flow path between said oxygen supply and said delivery apparatus, said flow sensor configured to generate information regarding a flow rate of oxygen delivered from said oxygen supply to said user; and

a processor arranged to calculate a time period which said valve should be maintained in its first position to cause a desired amount of oxygen to be delivered to said user when said oximeter indicates a blood-oxygen saturation level which is below said goal blood-oxygen saturation level and arranged to generate a signal for said time period, which signal applied to said valve moves said valve to said first position and causes oxygen to be delivered to said user when and a condition of inhalation is detected by said pressure sensor, and said signal when removed from said valve causes said valve to be moved to said second position, and said processor configured to utilize flow rate information generated by said flow sensor and trigger an alarm in the event said utilized flow rate information meets a predetermined criteria.

2. The apparatus in accordance with claim 1 including a memory associated with said processor, said memory configured to store flow rate information.

3. The apparatus in accordance with claim 1 wherein said alarm comprises an audible warning.

4. The apparatus in accordance with claim 1 wherein said alarm comprises a visual warning.

5. The apparatus in accordance with claim 1 wherein said processor, flow sensor, valve and pressure sensor are associated with a printed circuit board located within a housing and said selector comprises a user-actuatable input extending from said housing.

6. A method of controlling a flow of supplemental oxygen from an oxygen supply to a user through a delivery apparatus in an open-loop breathing system, the delivery apparatus including a valve moveable between a first position permitting oxygen to flow from said supply to said user and a second position for preventing oxygen to flow from said supply to said user comprising the steps of:

receiving a goal blood-oxygen saturation level of a user;

determining an actual blood-oxygen saturation level of a user;

determining a length of time said valve should be moved to said first position in order to deliver a desired quantity of oxygen to achieve said goal blood-oxygen saturation level based upon said actual blood-oxygen saturation level;

detecting the initiation of inhalation by said user;

moving said valve from said second position to said first position for said determined length of time when said inhalation is detected;

returning said valve to said first position; and

generating at two or more times information regarding an average flow rate of oxygen delivered from said supply to said user;

determining if a change in average flow rate exceeds a predetermined amount and, if so, triggering an alarm.

7. The method in accordance with claim 6 wherein said step of determining a blood-oxygen saturation level comprises measuring a blood-oxygen saturation level of said user with a pulse-oximeter.

8. The method in accordance with claim 6 wherein said step of determining the initiation of inhalation by a user comprises sensing a drop in pressure at said delivery apparatus.

9. The method in accordance with claim 6 wherein said predetermined amount comprises a predetermined percentage change in average flow rate.

10. The method in accordance with claim 6 wherein said step of triggering an alarm comprises illuminating a light.

11. The method in accordance, with claim 6 wherein said step of triggering an alarm comprises emitting an audible noise.

12. The method in accordance with claim 6 including the step of storing flow rate information received from said output of said flow sensor and utilizing said stored information to generate said average flow rate.

13. The method in accordance with claim 6 wherein said step of generating information regarding an average flow rate comprises generating flow rate information with a flow sensor and utilizing said flow rate information to generate information regarding average flow rate.

15. The method in accordance with claim 14 including the step of opening a valve to provide said amount of oxygen.

16. The method in accordance with claim 14 including the step of utilizing flow rate data received as an output of a flow sensor to calculate said average flow rate.

17. The method in accordance with claim 14 including the step of storing said flow rate data.

14. A method of controlling a flow of oxygen from an oxygen supply to a user comprising the following steps:

providing an amount of oxygen to a user in a breathing system, said amount of oxygen determined by comparing a desired blood-oxygen content level with a measured blood-oxygen content level, said amount of oxygen delivered to said user when a period of inhalation of said user is detected, said amount of oxygen provided to said user continuously automatically adjusted based upon said desired and measured blood-oxygen content levels; and

determining an average flow rate of oxygen delivered to said user and triggering an alarm if said overage flow rate of oxygen changes by an amount exceeding a predetermined amount.