Test electrode for argon plasma coagulation medical instrument

To provide the user of an RF-surgical instrument with a non-hazardous short test operation, for example so as to test the ignitability of an argon plasma probe, provision is made for an instrument test arrangement, which is installed into a feeding medical device or into a neutral conductor connecting cable or which is provided as plug adapter, which is to be plugged between the device and the neutral conductor connecting cable. The instrument test arrangement comprises at least one or, better yet, two ignition test electrodes, which are connected to conductors of the device or of the neutral conductor cable, preferably via impedance components. The ignition test electrodes can be accessed insofar as a spark can be created simultaneously to both ignition test electrodes by means of an operational probe or an instrument.

TECHNICAL FIELD

Embodiments of the invention relate to an instrument test arrangement in particular for medical instruments for argon plasma coagulation.

BACKGROUND

Argon plasma coagulation instruments utilize a spark, which is fed from a radio frequency (RF) generator to create an argon plasma. Prior to carrying out the actual treatments, users like to carry out a short test, so as to see, whether the instrument is operational. Damaged instruments and incorrect settings can thus be identified early and the use of such instruments on the patient can be avoided. In the case of probes or instruments for argon plasma coagulation, the ignition of the spark can be impacted negatively, if the last argon gas flushing had been performed a while ago or if a reusable probe, which has already been used, is used. Users, who had been faced with inferior ignition behavior of such probes in the past, tend to check the operability, in particular the ignitability, of the probe prior to the use thereof. This course of action is often also suggested by manufacturers of probes for argon plasma coagulation, so as to ensure, in particular in the case of endoscopic probes, that they are only inserted into the endoscope or are only used on the patient, respectively, if the probe or the instrument, respectively, works correctly as well as if matching settings were selected on the device.

A probe cannot simply be tried out on the patient, because injuries can be caused by this. The ignition test on metal parts, which are grounded in an undefined manner, is improper, because it can lead to injuries to patient and personnel as well as to damages to electrical and electronic equipment. It can nonetheless not be excluded that users carry out such improper tests.

From practice, ignition test adapters are known, which were brought on the market by the owner of the instant property right. Instead of the neutral electrode, such an ignition test adapter is to be plugged into the neutral socket of the feeding device and it comprises an electrode, which is grounded in a defined manner. A replugging at the device is thus required. This can have the result that the ignition test adapter is not used and that the user either does not carry out an ignition test or uses points, which are grounded in an undefined manner (equipment trolleys, infusion stands) for the ignition test after all again.

Based on this, it is the object of embodiments of the invention to specify a concept, by means of which the operability, in particular the ignitability, of an instrument or of a probe can be tested prior to the use on the patient in a comfortable manner.

For this purpose, embodiments of the invention provide for an instrument test arrangement, by means of which the probe or the medical instrument can be tested without any danger under defined conditions. The instrument test arrangement can be embodied as modified neutral conductor cable, as plug adapter or can be embodied at the feeding device itself.

The neutral conductor cable includes a connector for the neutral connection of the medical device. The flexible neutral conductor cable extends from the connector to a neutral electrode connection or to a neutral electrode arrangement. In one embodiment, the instrument test arrangement is arranged at the neutral conductor cable. The instrument test arrangement includes an ignition test electrode support, which comprises at least one ignition test electrode, which is connected electrically to the conductor of the cable.

The ignition test electrode support can be attached to the connector, can be built into the connector, can be embodied as part of the connector, can be arranged in the path of the flexible cable section or also at the neutral electrode connection or at the neutral electrode arrangement. The ignition test electrode support includes at least one ignition test electrode, which is connected electrically to the at least one conductor of the flexible cable section.

If the instrument test arrangement is embodied as plug adapter, it has a plug on the side of the device, where it is to be plugged in, and a socket on the side of the cable. Provision can be made between both for a rigid housing or for a cable section. In the latter case, the plug adapter forms a neutral conductor extension cable. The ignition test electrodes can be arranged at any suitable location of the plug adapter.

If the instrument test arrangement is embodied at the device itself, it can comprise one or two ignition test electrodes. If it has only one ignition test electrode, the latter is connected to the neural conductor, which leads to a split stage, which divides the neutral conductor into at least two conductors, which lead to partial electrodes of the neutral electrode arrangement. The split stage has the object of monitoring the correct attaching of the partial electrodes to a patient by means of resistance or impedance test. If the instrument test arrangement has two ignition test electrodes, they can be connected downstream from the two neural conductors, which lead to the two-pole or multi-pole neutral socket and from there to the neutral electrode arrangement via the neutral conductor cable.

In the case of all of the above-mentioned concepts, it is ensured that the circuit of the electric spark, which is ignited as an experiment, does not include the patient, so that negative impacting of the patient is impossible. The test can furthermore be carried out without having to remove the neutral electrode from the patient or the connector from the device. The instrument test arrangement according to embodiments of the invention thus also allows for the operational test in a busy environment with minimum expenditure of time.

The neutral conductor cable preferably comprises two (or more) neutral conductors, which extend from the device or from the plug to the neutral electrode connection or to the neutral electrode arrangement. Preferably, a neutral electrode, which is divided into a plurality of (at least two) partial electrodes, is used. The correct attaching of the two partial electrodes to the patient can be tested by measuring the impedance or the resistance between the two partial electrodes. Preferably, the feeding device includes a corresponding test connection, which measures the resistance between the two conductors and thus between the two partial electrodes attached to the patient. In the case of such a concept, the ignition test electrode support in each case comprises at least one ignition test electrode, which is connected electrically to the conductor, for each conductor. The connection between the ignition test electrode and the conductor is preferably established via a component comprising an electrical impedance, preferably comprising a resistive or capacitive characteristic. In so doing, it is avoided that the spark, which is ignited as an experiment, short-circuits the two conductors with one another or only contacts one of the conductors. Both cases could otherwise lead to an activation of a monitoring system, which tests the correct attaching of the partial electrodes of the neutral electrode arrangement.

Further details of advantageous embodiments of the invention are the subject matter of claims, the description and/or the drawings.

DETAILED DESCRIPTION

FIG. 1illustrates a medical device10for feeding an electrosurgical instrument11, which acts on biological tissue. The instrument11can be an instrument, which is used in open surgery, for laparoscopy or also for endoscopy, a so-called probe. In particular, the instrument11can be an argon plasma coagulation probe.

The current, which is introduced into the biological tissue by means of the instrument11, is returned to the device10via a neutral electrode arrangement12. The neutral electrode arrangement12comprises at least one, preferably two or more partial electrodes13,14, which belong to a neutral conductor cable15or which are connected to the latter. The neutral conductor cable15establishes a flexible connection between the neutral electrode arrangement12and the device10. At its end on the side of the device, the neutral conductor cable15comprises a connector16, which is plugged into the neutral socket17of the device10.

As is shown inFIG. 2, the neutral conductor cable15can be provided with an instrument test arrangement18, which serves the purpose of being able to test the ignitability and operability of the instrument11.

The instrument test arrangement18comprises at least one, preferably two ignition test electrodes19,20, which are connected electrically to conductors21,22of the neutral conductor cable15. The ignition test electrode19is connected to the conductor21, preferably via an impedance component, for example a resistive, preferably an ohmic component23. The resistance can be 20 Ohm, for example. Preferably, it lies within the range of between 10 and 50 Ohm. The ignition test electrode20is preferably also connected to the conductor22via a corresponding impedance component24. Its resistance, in turn, preferably lies within the range of between 10 Ohm and 50 Ohm, for example 20 Ohm. The two impedance components23,24can be embodied equally or also slightly differently.

The conductor21is connected to the first partial electrode13. The conductor22is connected to the second partial electrode14. A split circuit25is suggested only schematically inFIG. 2and serves the purpose of measuring the ohmic resistance or the impedance between the two partial electrodes13,14. In this manner, it is determined, whether both partial electrodes13,14, and thus the entire neutral electrode arrangement12, comprises a sufficient electrical contact to the patient.

The instrument test arrangement18comprising the two ignition test electrodes19,20can be arranged in the connector16, which is suggested inFIG. 2only in a schematic manner by means of dashes. It is illustrated somewhat more solidly inFIG. 9, wherein the reference numerals, which have already been introduced, are assumed and used. The connector16can consist of a plastic material or another insulating material, which forms an insulator body26. The connector16can also comprise a metal housing, into which a corresponding insulator body is inserted. A depression27, in which the two ignition test electrodes19,20are arranged, can be embodied in the insulator body26. As is shown inFIG. 11, for example, the ignition test electrodes19,20can be formed by means of two metal needles or wires, which cross one another at a slight distance. The illustration of the impedance components23,24was forgone inFIG. 9. It can be seen, however, that the two conductors21,22are guided to different contacts28,29of a connector pin, which projects away from the connector16. When being used, the connector pin is plugged into the neutral electrode socket of the device.

The device10and the instrument11as well as in particular the instrument test arrangement18operate as follows:

To carry out a treatment with the instrument11, the latter is initially connected to the device10, as is illustrated inFIG. 1. In addition, the neutral electrode arrangement12is attached to the human or animal patient. The user will then want to test the operability and in particular the ignitability of the instrument11. For this purpose, he brings the distal end of the probe or of the instrument11in the vicinity of the depression27and then activates the generator of the device10. If the instrument11is ignitable, a spark jumps to the ignition test electrodes19,20, wherein the current, which thus flows as an experiment, discharges via both conductors21,22to the device10. The neutral electrode arrangement12remains on ground potential. Due to the even current sharing, the split circuit25does not detect an error signal. It sees the same relationships as in the case of surgery or treatment at the patient.

In the case of the instant exemplary embodiment, the instrument test arrangement18is part of the connector16and thus part of a neutral conductor connecting cable30. The latter includes the connector16, the neutral conductor cable15as well as the neutral electrode arrangement12. In the alternative, it is also possible that, instead of the neutral electrode arrangement12, only a neutral electrode connection31belongs to the neutral conductor connecting cable30, to which one or a plurality of neutral electrodes are to be connected.

The instrument test arrangement18does not necessarily need to be arranged at the connector16. It can nonetheless be part of the neutral conductor connecting cable30. An exemplary embodiment for this follows fromFIG. 3. As can be seen, the instrument test arrangement18can be arranged in the path of the neutral conductor cable15between the connector16and the neutral electrode arrangement12. For this purpose, the instrument test arrangement18can comprise its own insulating housing, which is not illustrated further, in or at which the ignition test electrodes19,20are arranged. A modified instrument test arrangement according toFIG. 3can also comprise a connection possibility for the neutral electrode cable15, so that the neutral electrode cable15is embodied in two parts. A first part of the neutral electrode cable15, which is a part of the instrument test arrangement18, leads from the latter to the device10. A second part of the neutral electrode cable15is releasably connected to the instrument test arrangement18, for example by means of a plug-in connection and leads from the latter to the neutral electrode.

As shown inFIG. 4, the instrument test arrangement18can also be arranged at the neutral electrode arrangement12, for example at the neutral electrode connection31. The instrument test arrangement18, in turn, can comprise its own insulator housing or can be arranged in the neutral electrode connection31, for example.

In the case of a modified embodiment according toFIG. 5, the instrument test arrangement18is embodied as part of the device10. The ignition test electrode19is connected to the neutral conductor upstream of the split circuit25. In this case, a single ignition test electrode, which is arranged in an insulator housing in a recess, is sufficient.

In the case of a further modified embodiment according toFIG. 6, the instrument test arrangement18is embodied as plug adapter, which is arranged between the connector16and the neutral socket17. It can comprise its own insulating material housing, in which the ignition test electrodes19,20and the impedance components23,24, are arranged, in turn. The conductors21,22lead to a socket arrangement, which is provided at the plug adapter and into which the connector16is to be inserted. Otherwise, the above description applies accordingly.

The instrument test arrangement18can also be arranged at a separate socket17a, which, according toFIG. 7, is provided at the device10and which is switched electrically parallel to the socket17. The instrument test arrangement18, which, with the two test electrodes19,20, provides the user with a possibility for trying out a probe or his instrument, can be plugged into this separate socket17a, in turn. The above description also applies accordingly with regard to this in a supplementary manner.

A further embodiment follows fromFIG. 8. The instrument test arrangement18is installed into the device10similarly as inFIG. 5. However, provision is made for two ignition test electrodes19,20, which are arranged in or at the device10. For this purpose, the device10can comprise a corresponding insulator material body, which accommodates the two ignition test electrodes19,20, which, in turn, are exposed in a depression, for example. The above description applies in a supplementary manner.

To supplement the description, reference is made toFIGS. 11 to 14. Contrary to the illustration inFIG. 11, the ignition test electrodes19,20can comprise a variety of different shapes. According toFIG. 10, ignition test electrodes19,20, which are arranged in the depression28, can have different designs, for example. The ignition test electrode19can be embodied as wire or tip or as screen or mesh, respectively, below which the ignition test electrode20is arranged as screen, mesh, wire, conductive surface or conductive bowl.

In the alternative, it is possible to attach the ignition test electrode19,20to the wall of a depression27. For this purpose,FIG. 12illustrates an embodiment for this purpose, in the case of which the ignition test electrodes19,20are arranged in a bowl-shaped manner at the circumference of the cylindrical depression27.

In the alternative, the ignition test electrodes19,20, as shown inFIG. 13, can be arranged at the inner wall of the depression27as narrow curved strips, which, in turn, are spaced apart from one another in circumferential direction.

It is also possible to embody the ignition test electrodes19,20as axially distanced rings, as is shown inFIG. 14.

Further combinations of available presented electrode shapes are also possible, for example the arrangement of a ring-shaped ignition test electrode in combination with a needle or rod-shaped ignition test electrode according toFIG. 11.

To provide the user of an RF-surgical instrument11with a non-hazardous short test operation, for example so as to test the ignitability of an argon plasma probe, provision is made for an instrument test arrangement18, which is installed into a feeding medical device10or into a neutral conductor connecting cable30or which is provided as plug adapter, which is to be plugged between the device10and the neutral conductor connecting cable30. The instrument test arrangement18comprises one or a plurality of ignition test electrodes19,20, which are connected to conductors21,22of the device10or of the neutral conductor cable30, preferably via impedance components23,24. The ignition test electrodes19,20can be accessed insofar as a spark can be created simultaneously to both ignition test electrodes19,20by means of an operational probe or an instrument11.