Stimulation device for electrotherapy and method for checking polarity of contact electrodes

Abstract

The invention relates to a stimulation device for electrotherapy, in particular a defibrillator device and / or an external pacemaker device, comprising: at least two contact electrodes (11, 12) which can be applied to the patient's body at suitable stimulation locations and by means of which current pulses can be applied to the patient's (10) body, with the first of the at least two contact electrodes (11, 12) acting as an introduction electrode (12) with positive polarity and the second of the at least two contact electrodes (11, 12) acting as an extraction electrode (11) with negative polarity with respect to the emitted current pulses; and a current pulse generator (14) which is connected or can be connected to the contact electrodes (11, 12) by means of a line connection (21, 17). In order to simplify the correct positioning of the contact electrodes on the patient's body, a signal evaluation unit (15) is provided which is connected or can be connected to the contact electrodes (11, 12) for determining the application location of the contact electrodes (11, 12) on the patient's (10) body, with the aid of which, in a preferred embodiment, the polarity of the electrodes can also be automatically reversed.

Description

Technical Field

[0001] The invention relates to a stimulation device for electrotherapy, in particular a defibrillator device and / or an external pacemaker device, which comprises at least two contact electrodes which can be applied to the patient's body at suitable stimulation locations and by means of which current pulses can be applied to the patient's body, with the first of the at least two contact electrodes acting as a lead-in electrode with positive polarity and the second of the at least two contact electrodes acting as a lead-out electrode with negative polarity with respect to the emitted current pulses, and the stimulation device also has a current pulse generator which is or can be connected to the contact electrodes by a line connection. The invention also relates to a method for determining the polarity of contact electrodes applied to the patient's body. Background Art

[0002] Stimulation devices suitable for defibrillation or for use as external pacemakers are usually connected to the body of the patient to be treated via two contact electrodes, which are fixed (e.g. glued) to certain locations on the patient's upper body. In doing so, the contact electrodes are essentially identical, i.e. both electrodes can be used as lead-in electrodes and lead-out electrodes. With respect to the emitted current pulses, the electrode with positive polarity thus serves as the lead-in electrode, while the electrode with negative polarity serves as the lead-out electrode.

[0003] Therefore, the standard electrode positions for external pacemakers (Pacer) and defibrillators are "front-back" and "front-side". In the case of the "front-side" arrangement, the polarity of the electrode applied to the front (i.e. on the right side of the front upper chest) should be positive, while the polarity of the electrode applied to the side (i.e. below the (left) lateral axilla) is negative. In the case of the "front-back" arrangement, the electrode applied to the back (i.e. on the patient's back) should have a positive polarity, while the electrode applied to the front (i.e. on the chest) should have a negative polarity. The polarity of the electrodes is decisive for proper treatment, because the reversal of polarity significantly increases the coupling threshold, which may challenge the success of the treatment. It is understandable that, especially in emergency situations where rescuers may be under great time and psychological pressure, it is easy to inadvertently reverse the polarity on the electrodes used to perform defibrillation or establish a connection with an external pacemaker, in which case the success of the treatment is impaired or completely challenged. Summary of the invention

[0004] The object of the invention is to create a stimulation device of the type mentioned at the outset, with which the correct positioning of the contact electrodes on the body of the patient is simplified.

[0005] This object is achieved by the invention with the aid of a signal evaluation unit, which is connected or can be connected to the contact electrodes for determining the application position of the contact electrodes on the patient's body. In doing so, according to the method according to the invention, the polarity of the contact electrodes of a stimulation device for electrotherapy applied to the patient's body, in particular a defibrillator and / or pacemaker device, can be checked, wherein, with the aid of the contact electrodes applied to the patient's body, the body's own signals specific to the individual application positions of the contact electrodes are recorded and sent to the evaluation unit, wherein the evaluation unit determines the actual position of the contact electrodes on the patient's body based on the signals detected on the contact electrodes, such as their orientation and / or size. This can be displayed to the caregiver or doctor with the aid of a suitable display to guide them to manually reverse the polarity of the contact electrodes. Therefore, the device according to the invention can have a display device for displaying the application position of the lead-in electrode and the lead-out electrode on the patient's body.

[0006] It is particularly advantageous if the evaluation unit compares the polarity of the treatment current provided for the electrotherapy actually applied to the respective contact electrodes with the target polarity on the contact electrodes at the respective actual position and outputs a signal and / or changes the actual polarity to the target polarity if the actual polarity does not match the target polarity. In this way, not only is the caregiver or doctor given the corresponding polarity of the contact electrodes applied to the patient's body, but also, if necessary, the polarity has been reversed, or, in a particularly preferred advantageous manner, the device according to the invention itself immediately corrects the error when the electrodes are connected. Thus, the rescuer can rely on the fact that the patient will receive optimal treatment even if the electrodes were incorrectly applied (reversed). This can save valuable time.

[0007] In order to carry out the method according to the invention, the device is preferably provided with a switching device for reversing the line connection between the current pulse generator and the contact electrode. If the device has determined that the polarity of the contact electrode is incorrect, the switching device makes it superfluous to switch the cable connection between the contact electrode and the defibrillator / external pacemaker. The switching device may comprise a changeover switch, during the operation of which the polarity reversal occurs rapidly. It is therefore particularly advantageous if the evaluation unit can actuate the changeover switch in a controlled manner so that the changeover can take place automatically without manual intervention by an operator of the device.

[0008] The signal evaluated by the device may preferably be an ECG signal which is picked up by the electrodes at the locations where the contact electrodes are placed on the patient's body and sent to an evaluation unit of the stimulation device via a line connection connected thereto. Since the ECG signal differs significantly depending on the location of the contact electrodes, the location of the two contact electrodes on the patient's body can be clearly deduced from the features extracted from the DE-ECG derivation. Other types of signals that may be evaluated in order to derive the corresponding positions of the positioning of the contact electrodes may be, for example, biopotentials or the impedance of the tissue at the locations of the applied contact electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Further advantages and features of the invention will emerge from the following description and the accompanying drawings, in which preferred embodiments of the invention are explained in more detail by way of example. In the accompanying drawings:

[0010] Figure 1A A representation of the standard electrode position "anterior-lateral" for external pacemakers and defibrillators is shown;

[0011] Figure 1B A representation of the standard electrode positions “anterior-posterior” is shown;

[0012] Figure 2A It shows that according to Figure 1A Electrode positions for ECG signals obtained with correct polarity (above) and reversed polarity (below);

[0013] Figure 2B It shows that according to Figure 1B ECG signals obtained with correct polarity (top) and reversed polarity (bottom) for electrode positions; and

[0014] Figure 3 A schematic diagram of a stimulation device according to the invention for carrying out the method according to the invention is shown. DETAILED DESCRIPTION

[0015] Figure 1A and Figure 1B Two standard electrode positions are shown for arranging contact electrodes 11 , 12 on the body of a patient 10 , for example for an external pacemaker or defibrillator.

[0016] When applying the electrodes to a patient, it is important to ensure not only that they are correctly positioned, but also that the correct polarity of the electrical pulses introduced into the patient by the defibrillator or pacemaker via the electrodes 11, 12 is observed. Figure 1A and Figure 1BIn the two electrode positions shown, the polarity of the electrode 11 which is dotted should be negative, while the polarity of the electrode 12 which is shown as flat black should be positive. If the ECG signal recorded by the contact electrodes 11, 12 at the points shown is derived and recorded, then if the correct polarity is observed as described above, the values ​​obtained are respectively Figure 2A and Figure 2B The ECG signal path shown above. When the polarity is reversed, the course of the ECG response signal also changes; it is then respectively as Figure 2A and Figure 2B It can be seen that by reversing the polarity the characteristics of the recorded waveform change and based on this it is easy to see whether the polarity of the two contacting electrodes corresponds to the desired arrangement or has been reversed.

[0017] Figure 3 The stimulation device schematically shown in the figure and denoted as a whole by 13 comprises, in addition to the two contact electrodes 11, 12, a current pulse generator 14 and an ECG evaluation unit 15, which are connected to the contact electrodes 11, 12 via a conductor 16 and a connecting cable 17. The evaluation unit 15 has a display device 18 for visually representing the ECG signals picked up by the contact electrodes 11, 12, and a signal processing device 19, which is used to determine at which position on the patient's body the lead-in electrode 12 with positive polarity is located and where the lead-out electrode 11 with negative polarity is located based on the recorded ECG signals.

[0018] If the evaluation unit 15 detects that the two contact electrodes are at the target position ( Figure 1A and Figure 1B ), by operating the double conversion switch 20, the exchange of the line connection 21 of the contact electrodes 11, 12 from the current pulse generator 14 to the connecting cable 17 will be achieved. In this way, the polarity of the treatment current for electrotherapy provided by the current pulse generator 14 and applied to each contact electrode is compared with the target polarity on the contact electrode at each actual position, and if the actual polarity and the target polarity do not match, the actual polarity is changed to the target polarity. In a preferred exemplary embodiment, the polarity of the two contact electrodes is automatically reversed, so that the charging and discharging of the current respectively occur at the correct points on the body of the patient 19, without the need to disconnect the connecting cables between the electrodes and the current pulse generator and reconnect them after reversing the polarity.

Claims

1. A stimulation device for electrotherapy, - having at least two contact electrodes (11, 12) which can be applied to suitable stimulation locations on the patient's body, by means of which the patient's (10) body can be subjected to current pulses, wherein With respect to the emitted current pulses, a first contact electrode of the at least two contact electrodes (11, 12) acts as an introduction electrode (12) having a positive polarity and a second contact electrode of the at least two contact electrodes (11, 12) acts as an extraction electrode (11) having a negative polarity, and - having a current pulse generator (14) which is connected to the contact electrodes (11, 12) by means of a line connection (21, 17) or can be connected to the contact electrodes (11, 12) by means of a line connection (21, 17), The invention is characterized in that it has a signal evaluation unit (15), which is connected to the contact electrodes (11, 12) or can be connected to the contact electrodes (11, 12), wherein the stimulation device is arranged to record body-specific signals of the respective application positions of the contact electrodes by means of the contact electrodes (11, 12) applied to the patient's body and send the signals to the evaluation unit (15), wherein the evaluation unit (15) is configured to determine the actual application positions of the contact electrodes (11, 12) on the body of the patient (10) based on the signals detected by the contact electrodes (11, 12).

2. The stimulation device according to claim 1, characterized in that A display device (18) is provided for displaying the application positions of the lead-in electrode (12) and the lead-out electrode (11) on the body of the patient (10).

3. A stimulation device according to claim 1 or 2, characterized in that A switching device (19, 20) is provided for interchanging the line connections (21, 17) between the current pulse generator (14) and the contact electrodes (11, 12).

4. The stimulation device according to claim 3, characterized in that The switching device (19, 20) comprises a change-over switch (20).

5. The stimulation device according to claim 4, characterized in that The changeover switch (20) can be actuated in a controlled manner by the evaluation unit (15).

6. The stimulation device according to claim 1, characterized in that The signal is an ECG signal.

7. The stimulation device according to claim 1, characterized in that The stimulation device is a defibrillator and / or an external pacemaker device.

8. A method for checking the polarity of contact electrodes (11, 12) of a stimulation device (13) for electrotherapy applied to the body of a patient (10), wherein: With the aid of the contact electrodes (11, 12) applied to the patient's body, body-specific signals at the respective application locations of the contact electrodes are recorded and sent to an evaluation unit (15), wherein the evaluation unit (15) determines the actual position of the contact electrodes on the patient's body based on the signals detected at the contact electrodes (11, 12).

9. The method according to claim 8, characterized in that The evaluation unit (15) compares the polarity of the treatment current provided for the electrotherapy actually applied to each contact electrode with the target polarity on the contact electrode at each actual position, and if the actual polarity does not match the target polarity, outputs a signal and / or changes the actual polarity to the target polarity.

10. The method according to claim 8 or 9, characterized in that: The signal is an ECG signal.

11. The method according to claim 8, characterized in that The stimulation device is a defibrillator and / or an external pacemaker device.

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