Reliability-enhanced apparatus operation for re-breathing and methods of effecting same

• US 7,066,176 B2
• Filed: 06/04/2004
• Issued: 06/27/2006
• Est. Priority Date: 10/15/1998
• Status: Expired due to Fees

• Current Assignee: RIC INVESTMENTS LLC (Respironics Incorporated)
• Original Assignee: RIC INVESTMENTS LLC (Respironics Incorporated)
• Inventors: Wigforss, Eric P., Triunfo, John A Jr., Rich, David R, Gunneson, Paul B, Jaffe, Michael B
• Primary Examiner(s): Dawson, Glenn K.
• Application Number:
  US10/861,543
• Publication Number:
  US 20050028817A1
• Time in Patent Office: 753 Days
• Field of Search: 128/200.24, 128/203.12, 128/203.14, 128/203.23, 128/203.24, 128/204.18, 128/204.21, 128/204.22, 128/204.26, 128/205.11, 128/205.24, 128/205.23, 128/207.12, 12820714-20718, 251/25, 251/28, 251/29, 251/58, 137/219, 137/220
• US Class Current: 128/205.24
• CPC Class Codes: A61M 16/0045 Means for re-breathing exhaled gases, e.g. for hyperventilation treatment
• 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 16/0833 T- or Y-type connectors, e.g. Y-piece
• CPC Class Codes: A61M 16/085 Gas sampling
• CPC Class Codes: A61M 16/0858 Pressure sampling ports
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/103 the CO2 concentration
• CPC Class Codes: A61M 2205/16 with back-up system in case of failure
• CPC Class Codes: A61M 2230/432 partial CO2 pressure (P-CO2)
• CPC Class Codes: Y10T 137/7761 Electrically actuated valve
• CPC Class Codes: Y10T 137/8326 Fluid pressure responsive indicator, recorder or alarm

Abstract

Methods and apparatus for enhancing reliability of, and monitoring, the operation of airway valves to enhance patient safety. Pneumatic control line pressure (positive or negative) for actuation of the airway valve may be specified at a given magnitude or within a selected range and monitored continuously. Reduced or excessive pressure may be compensated by actuation of a pressure source or a bleed valve, and monitoring may be effected so as to warn the user of any deviation from the range, or deviations of selected magnitudes or frequencies or a combination thereof. The inspired volume of CO₂ may be monitored using air flow and CO₂ sensing, with detection of excessive CO₂ volume triggering a warning. Similarly, measured end-tidal or end-inspired CO₂ or other appropriate measures of CO₂ concentration may be employed as a warning trigger. Other driving energy sources for airway valves, and monitoring thereof, are also disclosed.

Claims

1. An airway valve system for affording a re-breathing capability to a breathing circuit, comprising:

a breathing circuit having first end adapted to be coupled an airway of a patient and a second end;

a pressure-actuated valve disposed in the breathing circuit between the first end and the second end, wherein the valve has a first mode responsive to a first level of actuation pressure for permitting a gas flow through the valve between the first end and the second end of the breathing circuit, and a second mode responsive to a second, different level of actuation pressure for diverting such a gas flow through an expanded volume operatively coupled to the breathing circuit;

a control line extending from a source of pressurized fluid to the valve to selectively effect a change in mode of the valve between the first mode and the second mode through a change in actuation pressure level;

first monitoring means for detecting a characteristic associated with such as gas flow in the breathing circuit;

second monitoring means for detecting a characteristic associated with the actuation pressure; and

a pressure controller, receiving an output of the first monitoring means and the second monitoring means and being operatively coupled to the control line, the source of pressurized fluid, or both, wherein the pressure controller is adapted to change the actuation pressure level applied to the valve via the control line based on the characteristics monitored by the first monitoring means and the second monitoring means.

2. The system of claim 1, wherein the first monitoring means is a flow sensor, a pressure sensor, a CO₂ sensor, or any combination thereof operatively coupled to the breathing circuit.

3. The system of claim 2, wherein the pressure controller comprises:

a pressure control valve operatively coupled to the control line such that actuation of the valve alters a pressure of fluid disposed in the control line; and

a valve control system adapted to receive the output of the first monitoring means and the second monitoring means, wherein the valve control system actuates the pressure control valve based on the output of the first monitoring means and the second monitoring means.

4. The system of claim 1, further comprising:

an alarm; and

alarming activating means, receiving an output of the monitoring means, for activating the alarm based on a characteristic monitored by the first monitoring means and the second monitoring means.

5. A method for affording a re-breathing capability to a breathing circuit, comprising:

providing a breathing circuit having first end adapted to be coupled an airway of a patient and a second end;

providing a pressure-actuated valve disposed in the breathing circuit between the first end and the second end, wherein the valve has a first mode responsive to a first level of actuation pressure for permitting a gas flow through the valve between the first end and the second end of the breathing circuit, and a second mode responsive to a second, different level of actuation pressure for diverting such a gas flow through an expanded volume operatively coupled to the breathing circuit;

providing a control line extending from a source of pressurized fluid to the valve to selectively effect a change in mode of the valve between the first mode and the second mode through a change in actuation pressure level;

detecting a first characteristic associated with such as gas flow in the breathing circuit;

detecting a second characteristic associated with the actuation pressure; and

changing the actuation pressure level applied to the valve via the control line based on the first characteristic and the second characteristic.

6. The method of claim 5, wherein detecting the first characteristic associated with such as gas flow in the breathing circuit including measuring a flow, a pressure, a CO₂ level, or any combination in the breathing circuit.

7. The method of claim 6, further comprising:

providing a pressure control valve operatively coupled to the control line such that actuation of the valve alters a pressure of fluid disposed in the control line; and

actuating the pressure control valve based on the characteristics monitored by the first monitoring means and the second monitoring means.

8. The method stem of claim 5, further comprising activating an alarm based on the characteristics monitored by the first monitoring means and the second monitoring means.