METHOD AND ARRANGEMENT FOR DETECTING A LEAK IN ANESTHESIA SYSTEM

• US 20100078018A1
• Filed: 09/23/2009
• Published: 04/01/2010
• Est. Priority Date: 09/26/2008
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: HEINONEN, Erkki Paavo, Haggblom, Tom Jakob
• Granted Patent: US 8,333,191 B2
• Time in Patent Office: Days
• US Class Current: 128/202.220
• CPC Class Codes: A61M 16/0081 Bag or bellow in a bottle
• CPC Class Codes: A61M 16/01 specially adapted for anaesthetising A61M16/104, A61M16/18 take precedence
• CPC Class Codes: A61M 16/085 Gas sampling
• CPC Class Codes: A61M 16/104 specially adapted for anaesthetics A61M16/18 takes precedence
• CPC Class Codes: A61M 16/14 by mixing different fluids, one of them being in a liquid phase
• CPC Class Codes: A61M 16/204 used for inhalation control
• CPC Class Codes: A61M 16/205 used for exhalation control
• CPC Class Codes: A61M 16/209 Relief valves
• CPC Class Codes: A61M 16/22 Carbon dioxide-absorbing devices ; Other means for removing carbon dioxidecartridges with absorbing substances for respiratory apparatus A62B19/00
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0036 in the breathing tube and used in both inspiratory and expiratory phase
• CPC Class Codes: A61M 2202/0208 Oxygen
• CPC Class Codes: A61M 2202/0275 Nitric oxide [NO]
• CPC Class Codes: A61M 2202/0283 Nitrous oxide (N2O)
• CPC Class Codes: A61M 2205/15 Detection of leaks
• CPC Class Codes: A61M 2230/432 partial CO2 pressure (P-CO2)

Abstract

A method and arrangement for detecting a leak in an anesthesia system. The method includes controlling respiratory movements by means of ventilator gas flows and measuring the ventilator gas flow added for an inspiration and removed for an expiration. The method also includes supplying a fresh gas flow for a respiration and measuring the fresh gas flow added for the respiration. The method further includes receiving information indicative of the measured gas flows, determining based on said received information both the gas volume added and the gas volume removed and comparing these determined gas volumes to each other. The method also includes determining based on comparing the anesthesia system leakage.

Claims

1. A method for detecting a leak in an anesthesia system, the method comprising:

controlling respiratory movements by means of ventilator gas flows;

measuring the ventilator gas flow added for an inspiration and removed for an expiration;

supplying a fresh gas flow for a respiration;

measuring the fresh gas flow added for the respiration;

receiving information indicative of the measured gas flows;

determining based on said received information both the gas volume added and the gas volume removed;

comparing these determined gas volumes to each other; and

determining based on comparing the anesthesia system leakage.

2. The method according to claim 1, wherein controlling respiratory movements by means of ventilator gas flows includes supplying gas flow for the inspiration and also includes removing gas flow for the expiration.

3. The method according to claim 1, wherein supplying a fresh gas for an inhalation includes an anesthetic agent vaporized and a gas flow of the anesthetic agent vaporized is measured by either together with other fresh gas flow or separately.

4. The method according to claim 1, further comprising:

receiving information indicative of known gas flow which can be one of an anesthetic agent vaporized among the fresh gas flow and a gas flow withdrawn for analyzing.

5. The method according to claim 1, further comprising:

measuring a total gas flow of the inspiration exploiting a single measurement and measuring the total gas flow of the expiration exploiting also a single measurement.

6. The method according to claim 1, further comprising:

analyzing the gas flow and in case analyzing requires removing the analyzed gas from the anesthesia system, this withdrawn gas information is part of receiving information indicative of the measured gas flows.

7. An arrangement for detecting a leak in an anesthesia system, the arrangement comprising:

a ventilator configured to control respiratory movements, including at least one flow sensor for measuring a ventilator gas flow added for an inspiration and removed for an expiration;

a gas mixer for supplying a fresh gas flow for a respiration, including at least one flow sensor for measuring the fresh gas flow added;

a breathing circuit configured to conduct an expiration gas flow to said ventilator and to conduct the fresh gas flow from said gas mixer for the respiration and to conduct the ventilator gas flow added for the inspiration;

a leak analyzer configured to receive information indicative of the measured gas flows of said flow sensors, wherein the leak analyzer is configured to determine based on said information both the gas

volume added and the gas volume removed and to compare these gas volumes to each other and to determine the anesthesia system leakage.

8. The arrangement according to claim 7, further comprising:

a patient flow sensor configured to measure a total gas flow of the inspiration and the expiration and which flow sensor locates in a patient tube of said breathing circuit.

9. The arrangement according to claim 7, wherein the ventilator connectable to a gas supply includes a reciprocating unit configured to guide respiratory movements,

wherein the reciprocating unit comprises:

a bellows in a bottle separating a gas flow between said gas supply and said breathing circuit, and

a sensor configured to indicate a position of the bellows inside the bottle,

which information together with other received information transmitted to the leak analyzer is used when determining the anesthesia system leakage.

10. The arrangement according to claim 7, further comprising:

a pressure sensor configured to measure a positive end-expiratory pressure (PEEP) and inform a change in the pressure between breaths to the leak analyzer when determining the anesthesia system leakage.

11. The arrangement according to claim 7, wherein the ventilator connectable to a gas supply includes a reciprocating unit configured to guide respiratory movements,

wherein the reciprocating unit comprises a channel that is part of a continuous flow pathway between said gas supply and said breathing circuit.

12. The arrangement according to claim 7, wherein a gas mixer includes an anesthetic agent supply configured to vaporize an anesthetic agent into the fresh gas flow, and

wherein information indicative of the measured or known gas flow of said anesthetic agent supply is received by said leak analyzer.

13. The arrangement according to claim 7, wherein the gas analyzer for analyzing the gas flow is configured to withdraw a sample of the gas flow, and

wherein information indicative of the measured or known gas flow of said gas analyzer is received by said leak analyzer.