Ventilation system

• US 7,162,296 B2
• Filed: 12/18/2003
• Issued: 01/09/2007
• Est. Priority Date: 12/21/2002
• Status: Active Grant

• Current Assignee: Dragerwerk AG & Company KGaA (FPS Vermögensverwaltung GmbH)
• Original Assignee: Drager Medical AG & Co KG (Dragerwerk AG)
• Inventors: Teschner, Eckhard, Leonhardt, Steffen
• Primary Examiner(s): Nasser; Robert L.
• Application Number:
  US10/742,356
• Publication Number:
  US 20040133123A1
• Time in Patent Office: 1,118 Days
• Field of Search: 600/547, 600529-543, 600/546, 128/204.23, 128/202.22
• US Class Current: 600/547
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/0536 Impedance imaging, e.g. by tomography
• 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 2230/08 Other bio-electrical signals

Abstract

A ventilation system (1, 10) is combined with a measuring method (2, 22, 222) for electric impedance tomography (EIT). Bidirectional data exchange between the two systems is provided. Both the ventilation system (1, 10) and the measuring system (2, 22, 222) have a first and second communications electronic unit (11, 12) each with associated transmitting and receiving means for the bidirectional data exchange.

Claims

1. A system comprising:

a ventilation system;

a measuring system for performing electric impedance tomography, said measuring system measuring impedance data during the electric impedance tomography in a time-dependent manner and transmitting the data to said ventilation system;

a filter separating the impedance data in a frequency-dependent manner; and

communication means for bidirectional data exchange between said ventilation system and said measuring system for the electric impedance tomography.

2. A system in accordance with claim 1, wherein said communication means for the bidirectional data exchange between the ventilation system and the measuring system comprises an electric wire connection.

3. A system in accordance with claim 1, wherein said ventilation system includes a first communications electronic unit with transmitting and receiving means for the wireless bidirectional data exchange and said measuring system has a second communications electronic unit with transmitting and receiving means for the wireless bidirectional data exchange.

4. A system in accordance with claim 3, wherein the bidirectional data exchange is performed by means of a directional radio link or an infrared transmission link.

5. A system in accordance with claim 1, wherein said filter is an adaptive high-pass filter or band pass filter is used to separate the impedance data relevant for cardiac activity, and an adaptive low pass filter or another band pass filter is used to separate the impedance data relevant for pulmonary or respiratory activity.

6. A system in accordance with claim 5, wherein the measuring system determines the current heart rate from the impedance data and transmits it to the ventilation system.

7. A system in accordance with claim 1, wherein the measuring system includes:

a plurality of electrodes E1 through En, which are arranged in an electrode belt form;

an analog connection line to an analog-digital interface circuit with an adjoining first digital connection line;

a monitor connected to said adjoining first digital connection line, said electric wire connection connecting said measuring system to the ventilation system.

8. A system in accordance with claim 1, wherein the measuring system

includes:

a plurality of electrodes arranged in a belt form;

an analog connection line to an analog-digital interface circuit with an adjoining electric wire connection and wherein said ventilation system includes;

an interface card connected to said electric wire connection, said interface card including evaluation and control functions of the measuring system.

9. A system in accordance with claim 1, wherein the measuring system includes:

a plurality of electrodes arranged in a belt form and with an analog connection line to an analog-digital interface circuit with an adjoining first digital connection line;

a first communications electronic unit with a transmitter and a receiver and said ventilation unit includes;

a second communications electronic unit with a transmitter and receiver.

10. A system in accordance with claim 1, further comprising:

a display connected to said ventilation system and said measuring system for simultaneously displaying tomograms and the impedance data from the measuring system and displaying ventilation data from the ventilation system.

11. A system in accordance with claim 10, wherein:

said display provides diagrams comparing the impedance data with ventilation data.

12. A method of monitoring a patient during ventilation, the method comprising the steps of:

providing a ventilator and connecting it to a patient and initiating respiration;

providing an electric impedance tomography measurement system and connecting it to the same patient and measuring with the electric impedance tomography measurement system, said measuring being activated depending on a ventilation pattern and/or a measured pressure or volume flow in the ventilator so that impedance data, which will be used as reference values for the impedance measurement that follow in time, are determined at predetermined points in the ventilation pattern; and

providing bidirectional data exchange between the ventilator and the measuring system.

13. A method in accordance with claim 12, wherein said ventilator is connected to a first communications electronic unit with transmitting and receiving means for the wireless bidirectional data exchange and said measuring system has a second communications electronic unit with transmitting and receiving means for the wireless bidirectional data exchange.

14. A method in accordance with claim 13, wherein the bidirectional data exchange is performed by means of a directional radio link or an infrared transmission link.

15. A method in accordance with claim 13, wherein measured impedance data are transmitted by the measuring system to the ventilator.

16. A method in accordance with claim 15, wherein the impedance data measured in a time-dependent manner are separated by means of at least one filter in a frequency-dependent manner.

17. A method in accordance with claim 16, wherein an adaptive high-pass filter or band pass filter is used to separate the impedance data relevant for cardiac activity, and an adaptive low pass filter or band pass filter is used to separate the impedance data relevant for pulmonary or respiratory activity.

18. A method in accordance with claim 17, wherein the measuring method determines the current heart rate from the impedance data and transmits it to the ventilation method.

19. A method in accordance with claim 12, wherein the ventilation is controlled by the measuring system as a function of the measured impedance data and after comparison with stored reference values.

20. A method in accordance with claim 19, wherein acoustic and/or optical alarm triggering units are present, so that an acoustic and/or optical alarm is triggered in the ventilator by the measuring system when actual values drop below or exceed limit values of the electric impedance which are stored in the ventilation method or in the measuring method.

21. A method in accordance with claim 12, wherein said measuring includes attaching a plurality of electrodes to the patient, providing an analog connection line to an analog-digital interface circuit with an adjoining first digital connection line and using a monitor connected to said adjoining first digital connection line to monitor the patient and said bidirectional data exchange includes one of:

transferring data over an electric wire connection between said measuring system and the ventilator;

transferring data over an electric wire connection via an interface card of the ventilator connected to said electric wire connection, said interface card receiving evaluation and control functions of the measuring method; and

transferring data via a first communications electronic unit with a transmitter and a receiver connected to the measuring system and a second communications electronic unit with a transmitter and receiver connected to the ventilator.

22. A method of monitoring a patient during ventilation, the method comprising the steps of:

providing a ventilator and connecting it to a patient and initiating respiration;

providing an electric impedance tomography measurement system connected to the patient and measuring electric impedance data with the electric impedance tomography measurement system in a time-dependent manner;

separating impedance data by an adaptive high-pass filter or band pass filter to separate the impedance data relevant for cardiac activity, and by an adaptive low pass filter or band pass filter to separate the impedance data relevant for pulmonary or respiratory activity;

determining a current heart rate from the impedance data and transmitting the hear rate to the ventilator;

providing bidirectional data exchange between the ventilator and the measuring system.

23. A system comprising:

a ventilation system;

a measuring system for performing electric impedance tomography, said measuring system determining a current heart rate from data collected during the electric impedance tomography and transmitting the data to said ventilation system;

communication means for bidirectional data exchange between said ventilation system and said measuring system for the electric impedance tomography.

24. A system comprising:

a ventilation system;

a measuring system for electric impedance tomography, said measuring system being activated depending on a ventilation pattern and/or a measured pressure or volume flow in said ventilation system so that impedance data, which will be used as reference values for an impedance measurement that follows in time, are determined at predetermined points in the ventilation pattern;

communication means for bidirectional data exchange between said ventilation system and said measuring system for the electric impedance tomography.

25. A system in accordance with claim 24, wherein the ventilation system is controlled by the measuring system as a function of the measured impedance data and after comparison with stored reference values.

26. A system in accordance with claim 25, wherein acoustic and/or optical alarm triggering units are present, so that an acoustic and/or optical alarm is triggered in the ventilation system by the measuring system when actual values drop below or exceed limit values of the electric impedance which are stored in the ventilation system or in the measuring system.

27. A system comprising:

a measuring system for performing electric impedance tomography, said measuring system measurement system including a plurality of electrodes El to En, which are connected by an analog connection lead to an analog-digital adapter circuit;

communication means connected to said measuring system for bidirectional data exchange to and from said measuring system;

a ventilation system connected communication means for bidirectional data exchange between said ventilation system and said measuring system, said ventilation system including evaluating data from said measuring system and controlling said measuring system.