SK277834B6 - Electrode unit for monitoring of bioelectric current of body - Google Patents

Abstract

Electrode unit is transparental for rontgen rays and consists of own electrode (1) and from bounding cable (2). Electrode (1) has active part creayed by disk pressing (3) from semiconductive rubber, on which frontal part is circular target (4) from fabric from carbon fibres saturated by electrolyte mainly by physiological saline and ring fixing part (5). On opposite part of disk pressing (3) of electrode (1) is formed the contact pit (8) on which is put the bounding connector (9) of bounding cable (2), into which is pressed the end of conductor (10) from carbon filaments, which represents the core of leading cable (2) fitted on second end with bounding connector (13).

Description

Technical field

BACKGROUND OF THE INVENTION The present invention relates to an electrode unit for monitoring body bioelectric currents, in particular for monitoring cardiac activity by means of an electrocardiograph which is transparent to X-rays and consists of an eiactrode and a lead-in cable, the electrode comprising an active part provided with attachment means and attachment to the body; cable.

The prior art

Up to now, disposable fluoride electrodes have been used to monitor the body's bioelectric currents by eacectrocardiography, the active part of which is an argentchloride plate. When monitoring special sections of electrocardiograms at a lower level, e.g. late ECG and Hiss beam potentials, however, it turns out that many types of known electrodes do not achieve sufficiently low intrinsic noise and polarizing voltage. A major disadvantage of the known Argentine chloride electrodes is also the fact that these electrodes are not transparent to X-rays, which hampers e.g. in coronary angioplasty, catheterization and coronary angioplasty.

There are also known electrodes for electrocardiographs which are already transparent to X-rays, but which do not achieve the necessary low intrinsic noise, so that they are not usable for the purposes for which the electrode unit according to the invention is solved. One such electrode is described in EP-PA 222 473 and consists of a disc of an electroconductive rubber containing fine particles or carbon fibers, the disc being bonded to a lead formed by a strip of flexible graphite formation. The active portion of the conductive rubber electrode is unable to provide the necessary electrode sensitivity, so that the weaker bioelectric currents are not able to transfer the electrode to the electrocardiograph.

Another known electrode of this kind, i. j. transparent to X-rays, as described in EP-PA 223 340, and consists of a ring cut from a flexible graphite foil, on the opposite side of which a strip is also provided of a flexible sheet of graphite material forming the lead wire and attached to the opposite side of the ring with an adhesive ring of the same diameter. For attachment to the patient's body, the electrode unit is provided with a self-adhesive foil extending over its peripheral portions over the electrode perimeter. This known electrode unit is intended for long-term attachment to the patient's body, so that its construction is adapted primarily for this purpose, and it is no longer so important that it has a higher intrinsic noise, that the strip conductor is disadvantageous for handling and that the electrode difficult to release.

Another electrode known from U.S. Pat. No. 4,300,575 has an active portion formed of a conductive ring formed from a mixture of carbon black, karaya, isopropylene alcohol, and a conductive solution of karay rubber, on which a silicone pad is mounted on the opposite side, on which metal wire. Even in this embodiment, the necessary low intrinsic noise values are not achieved and, moreover, the electrode is not transparent to X-rays.

Also known is an electrode of EP-PA 255 241 in which an electrically conductive active member is provided on the side facing the patient with a contact layer of a viscoelastic hydrophilic gel formed of water, a water-soluble electrolyte and a water-dispersed polymer which after being crosslinked, it is capable of forming a water-bound layer of water. Even this solution is not useful for the purpose for which the electrode according to the invention is to be used, since the electrically conductive active member, the lead wire clip and the lead wire itself are not transparent to the X-rays.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an embodiment of the electrode and its lead wire so that the entire electrode unit is transparent to X-rays, has very low intrinsic noise, and also a negligible polarizing voltage.

SUMMARY OF THE INVENTION

The drawbacks of these known electrodes are overcome by the electrode unit according to the invention, which consists in that the active part of the electrode is a semiconductive rubber disk molding, on the front side of which a target of a fibrous carbon fiber structure is fixed. The pin on which the power cord connection plug is attached.

In a preferred particular embodiment of the invention, the fibrous formation on the front side of the disk blank is a carbon fiber fabric which is saturated with an electrolyte, in particular a 10% saline solution.

The lead-in connector is formed of semiconducting rubber and is provided with a snap-in hole for mounting on the contact pin of the active portion of the electrode, wherein the lead-in carbon fibers insulated on the lead-in cable with a silicone sheath are pressed into the lead.

On the front side of the disc blank, in another preferred embodiment of the invention, a fixing portion of the electrode, which is a flat ring of deformable material, is provided around the central target with a self-adhesive layer facing away from the disc blank.

The fastening ring is preferably formed of a nonwoven fabric, or in another preferred embodiment of foamed polyurethane.

The whole electrode unit, i. j. as its own electrode, also the lead-in cable is perfectly transparent to X-rays, so it does not interfere with demanding and specific patient examinations. The electrode contact system is formed directly on the molding and is compatible with the connectors of the electrocardiograph monitors.

Tests have shown that the polarization voltage of the electrodes according to the invention is significantly lower and more stable than the prior art electrodes, in particular the chloride electrodes, and ranged between 2 and 10 mV in the samples tested. It has also been shown in tests to achieve an intrinsic noise of about 3 pV, which makes it possible to capture a significantly lower level of special electrocardiogram segments, e.g. late ECG and Hiss beam potentials, which have been difficult to follow with known electrodes or have not been detected at all. These advantageous physical properties of the electrode unit according to the invention have been achieved by an optimal combination of the materials of the individual elements of the unit.

Overview of the figures in the drawing

The invention is explained in more detail by way of an exemplary embodiment of the electrode unit shown in the drawing, wherein FIG. 1 shows a longitudinal section through an exploded electrode unit consisting of an electrode and a lead wire, and FIG. 2 is a front view of the active portion of the electrode after removal of the backing paper.

DETAILED DESCRIPTION OF THE INVENTION

The electrode unit according to the invention for monitoring the bioelectric currents of the body, in particular for monitoring cardiac activity by means of electrocardiographs, consists of the actual electrode laz of the lead-in cable 2, as shown in FIG. 1, wherein both of these basic components of the electrode unit are designed to be transparent to X-rays and to remain on the patient's body, e.g. in coronary angioplasty, catheterization and coronary angioplasty.

The active part of the electrode 1 is a semiconductive rubber disc molding 3, on the front side of which a circular target 4 of carbon fiber cloth is fixed, which is saturated with an electrolyte, e.g. 10% saline. Around this circular target 4, a fastening portion 5 of an electrode 1 in the form of a non-woven or foam polyurethane ring having the same thickness as the circular carbon fiber target 4 and which is provided over its entire cast a surface which faces away from the disk blank 3 with a permanent adhesive layer 6, which is covered with a covering paper 7 which, prior to use of the electrode 1, is torn off against application of the electrode 1.

The semiconductive rubber disk molding 3 is provided with a contact pin 8 which is formed directly from the material of the disk molding 3 on its rear side facing away from the side on which the circular target 4, which is the sensing element of the electrode 1, is mounted. created whole.

The connector pin 9 of the lead-in cable 2, which in the experimental embodiment according to FIG. 1 has the shape of a flat semiconductor rubber ring, the central opening of which has a shape adapted to the shape of the contact pin 8 of the electrode disk molding 3, to which the connection connector 9 can thus be snapped.

One end of the carbon fiber conductor 10, which is the core of the lead-in cable 2, is embedded in the connector 9 and is in an experimental embodiment embedded in a semiconductive rubber sheath 11 which is still provided with a silicone insulating sheath 12 on its periphery.

The other end of the carbon fiber conductor 10 is molded into a connector 13, also provided with a silicone insulating sheath 12 and having a shape adapted to be connected to the respective connector elements of the electrocardiograph.

The shape of the contact pin 8 of the disc blank 3 of the electrode 1 is preferably chosen such that the contact pin 8 is compatible with the connectors of the cardiac monitors and their lead wires unless transparent lead wires are required.

The sensing ring 4 of the electrode 1 may also be formed from a non-woven fibrous formation of carbon fibers, wherein the electrolyte may also be a liquid other than saline.

The electrode 1 of the electrode unit according to the invention may have different designs, different from the illustrated example, and adapted for different specific applications. The simplest embodiment of the electrode is represented only by a semiconductive rubber disk molding 3, provided with a circular target 4 of a carbon fiber fibrous structure saturated with an electrolyte over its entire front surface. In addition to the basic experimental embodiment of the electrode 1 shown in FIG. 2, where a fastening part 5 made of pearl or other nonwoven fabric, which is formed in the form of a ring with a diameter of 40 mm and provided with a permanent adhesive layer 6, is fastened around the circular target 4, e.g. creating an electrode for a stress test in which sweating patients need to use a 60 mm diameter self-adhesive ring to form the electrode mounting portion 5. For long-term monitoring, an electrode having a reduced diameter of a semiconductive rubber disk molding, about 2 cm in diameter, and a ring-shaped fastening portion of foamed polyurethane is suitable for long-term monitoring.

Claims (6)

PATENT CLAIMS An electrode unit for monitoring body bioelectric currents, in particular for monitoring cardiac activity by means of an electrocardiograph, comprising an electrode and a lead-in cable, the electrode comprising an active part provided with attachment means for attaching to the body and connected to the lead-in cable, the active part of the electrode (1) is a disc molding (3), especially of semiconducting rubber, on the front side of which a disc (4) of a fibrous carbon fiber structure is fixed and a contact pin (8) is formed on the opposite side. the connector (9) of the power cable (2). The electrode unit according to claim 1, characterized in that the fibrous formation on the front side of the disc blank (3) is a carbon fiber fabric saturated with an electrolyte, in particular saline. Electrode unit according to claim 1 or 2, characterized in that the connection plug (9) of the lead-in cable (2) is made of semiconducting rubber and is provided with a central hole for mounting on the contact pin (8) of the active part of the electrode (1). wherein the end of the carbon fiber conductor (10), which is the core of the supply cable (2), provided with an insulating sheath (12), in particular of silicone, is pressed into the connection connector (9). Electrode unit according to at least one of Claims 1 to 3, characterized in that the disc blank (3) of the electrode (1) is provided around the central target (4) with a fastening part (15) of the electrode (1) which is a flat ring of deformable. material, provided on the side facing away from the disk molding (3), with a permanent adhesive layer (6), covered with a covering paper (7). The electrode unit according to claim 4, characterized in that the fastening part (5) of the electrode (1) is a flat non-woven ring. The electrode unit according to claim 4, characterized in that the fastening part (5) of the electrode (1) is a flat ring of foamed polyurethane.