JP2015192711A - nerve stimulation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nerve stimulation device suppressing failure due to application of too much test stimulation.SOLUTION: There is provided a nerve stimulation device which is left in a living body to provide electric stimulation to nerve. The nerve stimulation device comprises: a nerve stimulation electrode comprising a stimulation electrode applying electric stimulation to nerve and a lead part 21 connected to the stimulation electrode at one end part; a stimulation generation device 10 connected to the other end part of the lead part and generating a nerve stimulation signal for applying electric stimulation; and a test stimulation button 15 causing the stimulation generation device to generate a test stimulation signal for specifying the left position of the stimulation electrode upon being operated. Input to the test stimulation button 15 is terminated after elapse of a predetermined time period after operation of the test stimulation button 15.

Description

  The present invention includes a nerve stimulation device, more specifically, a nerve stimulation electrode that is used in nerve stimulation treatment by being placed in a luminal tissue such as a blood vessel (blood vessel, lymphatic vessel), digestive tract, airway, urinary tract, and the like. The present invention relates to a nerve stimulation apparatus.

  Conventionally, research on treatment methods by applying electrical stimulation to nerve tissue has been performed. As one of the nerve stimulation devices, it has been proposed to insert a device including an electrode into a blood vessel and stimulate the nerve adjacent to the blood vessel through the blood vessel wall by the electrode (see, for example, Patent Document 1). .

  In the configuration described in Patent Document 1, unlike the case where the nerve is exposed by surgery and the electrode is directly attached to the nerve, the situation around the electrode cannot be seen directly. It is realistic to arrange the electrodes while confirming using the above means. In order to confirm that the electrode is disposed at a position where the nerve can be effectively stimulated, it is necessary to apply a stimulation pulse on a trial basis and observe the reaction of the living body.

  Even when the conditions such as the nerve to be stimulated, the arrangement position of the electrode, and the electrode shape are the same, the condition of the nerve stimulation for obtaining a desired biological reaction varies depending on the patient. Therefore, in order to know the relative positional relationship between the electrode and the nerve by applying a test stimulus pulse, the stimulus is output continuously with the stimulus intensity at which the stimulus effect clearly appears in many patients. . By doing so, the time required for the indwelling procedure can be shortened, and the patient's discomfort and the trouble of the operator can be reduced.

Special table 2010-516405 gazette

  On the other hand, such stimulation conditions suitable for experimental stimulation tend to be stronger or longer than during treatment to ensure a biological response, and cause some side effects due to nerve overactivity in some patients There is a fear. Therefore, adding more experimental stimuli than necessary may put an unexpected burden on the patient.

  This invention is made | formed in view of the said situation, Comprising: It aims at providing the nerve stimulating device which suppresses the malfunction by adding experimental stimulation more than necessary.

  A first aspect of the present invention is a nerve stimulation device that is placed in a living body and performs electrical stimulation on a nerve, the stimulation electrode that applies the electrical stimulation to the nerve, and one end connected to the stimulation electrode. A nerve stimulation electrode having a lead portion; and a stimulus generator connected to the other end of the lead portion to generate a nerve stimulation signal for applying the electrical stimulus; A test stimulus input unit that causes the apparatus to generate a test stimulus signal for specifying the indwelling position of the stimulus electrode, and the input to the test stimulus input unit is a predetermined time after the test stimulus input unit is operated. Then, it is stopped.

The test stimulus input unit may be provided in the lead unit.
The test stimulus input unit may be detachably provided on the stimulus generator.

The stimulus generation device may accept an input to the test stimulus input unit only when an operation of placing the nerve stimulation electrode is performed.
In this case, the apparatus further includes a tubular member that is inserted into the living body and into which the nerve stimulation electrode is inserted when the stimulation electrode is placed, and the stimulation generator includes the nerve stimulation electrode that is inserted into the tubular member. Only when the input to the test stimulus input unit may be accepted.
Alternatively, the apparatus further comprises a stylet inserted into the lead portion when the stimulation electrode is placed, and the stimulus generator is input to the test stimulus input portion only when the stylet is inserted into the lead portion. May be accepted.

  According to the nerve stimulation apparatus of the present invention, it is possible to suppress problems caused by an operation input for performing a test stimulus unintentionally by a patient or the like.

It is a mimetic diagram showing the whole nerve stimulation device composition concerning a first embodiment of the present invention. It is a schematic diagram which shows the external appearance of the stimulus generator in the nerve stimulating device. It is a functional block diagram of the same stimulus generator. It is a flowchart which shows the flow of the technique which pinpoints the appropriate position of the electrode part in the blood vessel at the time of use of the same nerve stimulation apparatus. It is a figure which shows the test stimulus button in the modification of this embodiment. It is a figure which shows the test stimulus unit in the modification of this embodiment. It is a figure which shows the state by which the lead part of the nerve stimulation apparatus which concerns on 2nd embodiment of this invention was penetrated by the tubular member. It is a figure which shows the cross section of the lead part in the other pattern of the embodiment. It is a figure which shows the lead | read | reed part and stimulus generator in the other pattern of the embodiment. It is an enlarged view which shows the nozzle | cap | die of the lead part. It is a front view of the stylet inserted in the lead part. It is a figure which shows the irritation | stimulation generator in the modification of this invention. (A) And (b) is a figure which shows the irritation | stimulation apparatus in the other modification of this invention.

A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic diagram showing an overall configuration of a nerve stimulation apparatus 1 of the present embodiment. The nerve stimulation device 1 is for electrically stimulating the vagus nerve Vn of the patient P or the like to treat tachycardia, chronic heart failure, and the like. The nerve stimulation device 10 generates a nerve stimulation signal, and the stimulus generation device 10. And a nerve stimulation electrode 20 placed in the blood vessel Bv.

The nerve stimulation electrode 20 is placed in a blood vessel of a patient or the like, applies a nerve stimulation signal generated by the stimulation generator 10 to a living tissue, and performs electrical stimulation to the nerve.
The nerve stimulation electrode 20 includes an electrode unit 30 having a pair of stimulation electrodes 30 </ b> A and 30 </ b> B that apply a nerve stimulation signal, and a lead unit 21 that connects the electrode unit 30 and the stimulation generator 10. If necessary, the electrode part 30 may further be provided with a locking member or the like for preventing displacement in the blood vessel.

  As a material of the electrode part 30, a metal material excellent in biocompatibility is preferable, and examples thereof include a noble metal material such as a platinum iridium alloy. In the present embodiment, the stimulation electrode 30A on the distal end side is a negative electrode, and the other stimulation electrode 30B is a positive electrode, and each is connected to the stimulation generator 10 by wiring (not shown) that passes through the lead portion 21. The number of stimulation electrodes is not limited to a pair, and a plurality of stimulation electrodes may be provided.

  The lead portion 21 has a known configuration including an insulating coating and a connector, and is configured to be long and flexible.

  FIG. 2 is a schematic diagram showing the appearance of the stimulus generator 10. The stimulus generator 10 includes a display unit 11 that displays various types of information on the outer surface, and an interface unit 12 that performs various operations of the stimulus generator 10. As the display unit 11, a known configuration such as a display using a liquid crystal screen or an LED can be appropriately selected and used. The interface unit 12 includes a setting button group 13 for performing various settings, an output button 14 for performing stimulation under the conditions set by the setting button group 13, and a test stimulation button for performing a test stimulation described later. (Test stimulus input unit) 15 and an output button 14 and a stop button 16 for canceling the output of the test stimulus button 15 are provided.

FIG. 3 is a functional block diagram of the stimulus generator 10. The stimulus generator 10 includes a stimulus generator 41 that generates a nerve stimulus signal, a biological information detector 42 that detects biological information such as a heart rate, and a controller 43 that controls the entire stimulus generator 10. Yes. A biological information acquisition electrode (not shown) is connected to the biological information detection unit 42, and biopotential information and the like for acquiring an electrocardiographic waveform are sent from the biological information acquisition electrode. There is no restriction | limiting in particular about the structure of a biometric information acquisition electrode, You may provide on the nerve stimulation electrode 20, and may be separately connected to a stimulus generator.
The control unit 43 is connected to the buttons of the display unit 11 and the interface unit 12, and based on the input from the interface unit 12 and the information from the biological information detection unit 42, various parameters (voltage value, Pulse width, frequency, etc.) are determined and transmitted to the stimulus generator 41. The stimulation generation unit 41 generates a nerve stimulation signal based on the setting received from the control unit 43 and sends it to the electrode unit 30 via the lead unit 21.

When the output button 14 is pressed, a nerve stimulation signal having a parameter set by the setting button group 13 is generated. When the test stimulus button 15 is pressed, a test stimulus signal having a predetermined parameter is generated regardless of the parameter set by the setting button group 13. Various parameters are set for the test stimulus signal so as to increase the probability of obtaining a neural response, which will be described later, to be a stronger stimulus for the living body than a general nerve stimulus. In addition, a general nerve stimulation signal is composed of a unit in which the time of electrical stimulation is performed and the time of rest, but in the case of a test stimulus signal, if there is a rest time, the placement position is appropriate. Since it becomes difficult to determine whether or not there is a break, it is preferable that the electrical stimulation is performed almost continuously with no break time and continuous or very short breaks.
In addition, in the test stimulus signal, the stimulus may increase stepwise to become the final stimulus intensity, and the specific signal mode can be appropriately set.

  When the nerve stimulation apparatus 1 configured as described above is used, a small incision is made in the patient's blood vessel, the nerve stimulation electrode 20 is inserted into the blood vessel, and the electrode unit 30 is placed at an appropriate position in the blood vessel Bv. . Thereafter, the stimulus generator 10 is fixed to the skin, the skin, or clothes. When the biometric information detection unit 42 determines that a predetermined condition such as tachycardia is satisfied based on the information sent from the biometric information acquisition electrode, the control unit 43 uses conditions set in advance in the stimulus generation unit 41. A neural stimulation signal is generated. The nerve stimulation signal is applied to the living body from the electrode unit 30, and the vagus nerve Vn is stimulated through the blood vessel wall, and a desired effect such as normalization of the heart rate is exhibited.

  In the neurostimulator 1, it is important for treatment that the electrode unit 30 is placed at an appropriate position. However, it is not easy to directly observe the inside of the blood vessel with an endoscope or the like, and the inside of the blood vessel is observed. However, the positional relationship between the parallel vagus nerve Vn and the electrode unit 30 cannot be immediately grasped. Therefore, it is difficult to specify an appropriate position with a single placement, so a test stimulation signal is applied from the placed electrode section, and the appropriate placement position of the electrode section is identified while confirming the biological reaction to this. , Detain.

  FIG. 4 is a flowchart showing an example of the procedure for specifying the appropriate position described above. In step S10, the operator makes a small incision in the patient's blood vessel to form an opening, inserts a cylindrical introducer or the like into the blood vessel, and places the nerve stimulation electrode 20 into the blood vessel via the introducer or the like. insert. Then, while confirming the blood vessel and the electrode unit 30 with an X-ray fluoroscopic image or the like, the electrode unit 30 is temporarily installed at a position considered to be appropriate within the blood vessel. Separately, attach an electrocardiograph to the patient so that the patient's ECG waveform can be confirmed.

  In the subsequent step S20, when the surgeon presses the test stimulation button 15 of the nerve stimulation device 10, a test stimulation signal is generated by the stimulation generation unit 41 and applied to the living body from the electrode unit 30.

In step S30, the surgeon confirms whether or not there is a patient's neural response to the test stimulus signal. The presence / absence of a neural response is determined by confirming the presence / absence of changes in the electrocardiographic waveform and the presence / absence of a biological reaction of the patient such as cough.
When the determination in step S30 is No, the process proceeds to step S31, and the operator moves the electrode unit 30 in the axial direction of the nerve stimulation electrode 20 or around the axis to adjust the position of the electrode unit 30. Thereafter, step S20 is executed again. When the determination in step S30 is Yes, the process is terminated because an appropriate position has been identified, and the electrode unit 30 is fixed with the position as an indwelling position. Thereafter, the surgeon sets parameters of the nerve stimulation signal in the treatment using the setting button group 13 while confirming the specific content of the nerve response.

  As described above, the test stimulation signal has a greater load on the patient than the nerve stimulation signal used for treatment. Therefore, in the nerve stimulation apparatus 1 of the present embodiment, various mechanisms are provided in the test stimulation button 15 in order to suppress unnecessary application of the test stimulation signal. Details will be described below.

Pattern 1: Input mode to the control unit at the time of test stimulus input unit operation In this pattern, the mode of operation input to the control unit 43 when the test stimulus button 15 is operated is set to a predetermined one for test stimulus. Suppress unnecessary application of signals. For example, the test stimulus button 15 is configured to return to the position before the operation when the hand is released, and the operation is input only when the test stimulus button 15 is pressed with a finger or the like. Thereby, even if a patient etc. touches the test stimulus button 15 unintentionally, since the input is cut off immediately after the button is released, unnecessary application of the test stimulus signal is suppressed. Note that the configuration of the test stimulus input unit is not limited to the buttons of the present embodiment, and it is natural that various types of input mechanism structures such as a dial, a lever, and a slide switch can be used.
In addition, when the test stimulus input unit is operated, the input may be continued for a predetermined time and thereafter the input may be cut off. In this case, in order to specify the indwelling position, it is necessary to repeatedly operate the test stimulus input unit. However, if the patient touches the test stimulus input unit unintentionally, the input is cut off in a predetermined time, which is unnecessary. Application is suppressed. The predetermined time until the input is cut off may be set as appropriate, for example, 60 seconds, 180 seconds, etc. according to the indwelling site. In such a case, it is naturally preferable that the application of the test stimulus signal is immediately stopped by pressing the stop button 16.

Pattern 2: Position and Structure of Test Stimulus Input Unit In this pattern, unnecessary application of a test stimulus signal is suppressed by making the arrangement and structure of the test stimulus button 15 predetermined.
In the modification of the present embodiment shown in FIG. 5, the test stimulus button 15 is attached to the lead portion 21 and connected to the stimulus generator 10 with a cable 45. By disposing the test stimulus input unit at a position away from the stimulus generator, the possibility that the patient or the like unintentionally touches the test stimulus button 15 is reduced, and unnecessary application of the test stimulus signal is suppressed. In the procedure of specifying the appropriate position of the electrode unit 30, the surgeon holds the lead portion 21 and adjusts the position of the electrode unit 30. In this modification, the surgeon uses the test stimulus input unit during the procedure. There is also an advantage that it is easy to operate.

In the modification shown in FIG. 6, the test stimulus button 15 is detachable from the stimulus generator 10. The test stimulus unit 51 including the test stimulus button 15 is provided with a connector pin 52, the connector pin 52 is inserted into a hole 53 provided in the stimulus generator 10, and the test stimulus unit 51 is attached to the stimulus generator 10. The The control unit 43 accepts an input of the test stimulus button 15 only when the test stimulus unit 51 is attached to the stimulus generator 10. In this modification, when the operator removes the test stimulus unit 51 from the stimulus generator 10 after the placement of the electrode part 30 is completed, the test stimulus button 15 can be completely prevented from being operated unintentionally. . As a modification of this aspect, the test stimulus button 15 shown in FIG. 5 can be attached to and detached from the cable 45, or the cable 45 can be attached to and detached from the stimulus generator 10, and the electrode generator 30 can be removed from the stimulus generator 10 after placement. It is good also as a structure which can be removed.
In addition, although the test stimulus input unit itself cannot be removed from the stimulus generation device 10, the control unit 43 may accept the input of the test stimulus input unit only when a restriction releasing member such as a key is attached to the stimulus generation device 10. In this way, only a medical staff such as an operator can manage the restriction release member, thereby preventing an unintended operation of the test stimulus input unit by a patient or the like. The configuration of the restriction release member is not particularly limited. For example, the control unit may detect the attachment of the restriction release member and switch the input reception, or a test stimulus input such as pressing a button only when the restriction release member is attached. It is good also as a structure where operation of a part is mechanically permitted.

  As described above, according to the nerve stimulation apparatus 1 in each pattern of the present embodiment, the test stimulation signal for the patient is not required by various mechanisms provided in the test stimulation button 15 as the test stimulation input unit. Application is suppressed. As a result, it is possible to quickly place the electrode unit 30 in an appropriate position using the test stimulus signal while suppressing the burden on the patient due to the test stimulus signal.

In this embodiment, in order to make it easier for the patient or medical staff to recognize that the test stimulus input unit has been operated, the test stimulus is emitted so as to emit light or sound or change color when operated. An input unit may be configured.
Moreover, it is good also as a structure which was always separated from the irritation | stimulation apparatus as a structure which can input a test stimulus input part by remote control.

  Next, a second embodiment of the present invention will be described with reference to FIGS. The difference between this embodiment and the first embodiment is an input restriction mode for the test stimulus input unit. In the following description, the same components as those already described are denoted by the same reference numerals and redundant description is omitted.

  As described in the first embodiment, the nerve stimulation electrode 20 is inserted into a tubular member such as an introducer or a cannula and introduced into a blood vessel. Since the lead part 21 has flexibility, when adjusting the position of the electrode part 30 in the blood vessel, a stylet (core metal) made of metal or the like is often inserted into the lead part 21. After the appropriate position of the electrode part 30 is specified, the tubular member is removed by being removed or torn. In the present embodiment, based on such a procedure flow, the control unit 43 is configured to receive an input from the test stimulation input unit only when the nerve stimulation electrode is in the indwelling process.

Pattern 3: Accepts input only when the lead part is inserted into the tubular member. FIG. 7 shows the lead part 61 of the nerve stimulation electrode 20 and the tubular part through which the lead part 61 is inserted in the nerve stimulation apparatus of this embodiment. The member 70 is shown. On the outer peripheral surface of the lead portion 61, a convex portion 62 is provided that moves in the radial direction of the lead portion 61 and can project and retract with respect to the outer peripheral surface. The projecting portion 62 can be separated and contacted with a contact (not shown) provided in the lead portion 61 by a projecting and retracting operation.
When the lead part 61 is inserted into the tubular member 70, the convex part 62 comes into contact with the inner surface of the tubular member 70 and is pressed as shown in FIG. The control unit 43 monitors contact / non-contact between the convex portion 62 and the contact point, and accepts an input of the test stimulus button 15 only when both are in contact.

  In this pattern, when the convex part 62 is not immersed, the control part 43 does not accept the input of the test stimulation button 15, so that only when the nerve stimulation electrode 20 is inserted through the tubular member 70 and in the indwelling process. Input from the test stimulus input unit is possible. Therefore, similarly to the first embodiment, the electrode unit 30 can be quickly placed at an appropriate position using the test stimulation signal while suppressing the burden on the patient due to the test stimulation signal.

Pattern 4: Accepts input only when a stylet is inserted in the lead portion. FIG. 8 shows a cross-sectional view of the lead portion 71 in the nerve stimulation electrode 20 of this pattern. In FIG. 8, wirings connected to the electrode unit 30 are omitted.
A pair of contacts 72 are exposed on the inner surface of the lead portion 71, and a conducting portion 76 is provided on the outer peripheral surface of the stylet 75 inserted into the lead portion 71. The conductive portion 76 is provided on the outer peripheral surface of the stylet 75 so as to be continuous in the circumferential direction. Since the diameter of the stylet 75 is substantially the same as the inner diameter of the lead portion 71, when the stylet 75 is inserted into the lead portion 71, the conducting portion 76 comes into contact with the pair of contacts 72, and the pair of contacts 72 is conducted. The The control unit 43 monitors conduction / non-conduction of the pair of contacts 72 and accepts an input of the test stimulus button 15 only when both are in contact.

  9 to 11 show a modification of this pattern. As shown in FIG. 9, the lead portion 81 is branched on the proximal end side, and a stylet insertion portion 82 is provided. As shown in FIGS. 9 and 10, the insertion portion 82 is provided with a base 83, and a pair of contacts 84 is provided on the end surface of the base 83. A fitting member 86 that fits into the base 83 is attached to the base end of the stylet 85. A ring-shaped conducting portion 87 is provided on the inner surface on the distal end side of the fitting member 86. When the stylet 85 is inserted into the lead portion 81 and the fitting member 86 is fitted into the base 83, a pair of contacts 84 is conducted by the conducting portion 87. The control unit 43 monitors the conduction / non-conduction of the pair of contacts 84 and accepts the input of the test stimulus button 15 only when both are in contact.

  In this pattern, when the stylet is not inserted into the lead portion, the control unit 43 does not accept the input of the test stimulation button 15, and therefore, as in the pattern 3, the test is performed only when the nerve stimulation electrode 20 is in the indwelling process. Input from the stimulus input unit is possible. Therefore, similarly to the first embodiment, the electrode unit 30 can be quickly placed at an appropriate position using the test stimulation signal while suppressing the burden on the patient due to the test stimulation signal.

  The embodiments of the present invention have been described above. However, the technical scope of the present invention is not limited to the above-described embodiments, and the combinations of the components or the components may be changed without departing from the spirit of the present invention. It is possible to make various changes to or delete them.

For example, in each of the above-described patterns, an auxiliary mechanism that can more reliably suppress the input of the test stimulus input unit after placement may be provided.
Since the nerve stimulation electrode is a foreign substance with respect to the living body, a drug that suppresses thrombus formation may be administered into the blood vessel by infusion or the like during placement. In the example shown in FIG. 12, when the tube (infusion line) 91 used for drug administration is fixed to the stimulus generator 10 and the test stimulus unit 51 is attached to the stimulus generator 10, the opening of the tube 91 is the test. The stimulation unit 51 is covered. If the surgeon forgets to remove the test stimulus unit 51 from the stimulus generator 10, the test stimulus button 15 can be operated even after indwelling. In this example, the drug is administered unless the test stimulus unit 51 is removed. Therefore, it is possible to prevent forgetting to remove the test stimulation unit 51.

  Further, in the example shown in FIG. 13A, the stimulus generator 10 is provided with a clip 95 for fixing to clothes or the like. When the clip 95 is closed during fixing, the test stimulus button 15 is covered with the clip 95 as shown in FIG. In this example, even if an external force is applied to the stimulus generation device 10 after the placement, the clip 95 is hindered and the test stimulus button 15 is suppressed from being operated.

  Further, in each of the above-described embodiments, the example in which the nerve stimulation electrode is placed in the blood vessel has been described. However, the electrode is placed in another lumen tissue such as a lymphatic vessel, digestive tract, airway, urinary tract, etc. Even when the nerve is stimulated through the cavity tissue, it is necessary to specify the indwelling position using the test stimulation signal. Therefore, the present invention can be applied to these cases.

1 Nerve Stimulator 10 Stimulus Generator 15 Test Stimulus Button (Test Stimulus Input Unit)
20 Neural stimulation electrodes 21, 61, 71, 81 Lead portions 30A, 30B Stimulation electrodes

Claims (7)

A nerve stimulation device that is placed in a living body and electrically stimulates nerves,
A nerve stimulation electrode having a stimulation electrode for applying the electrical stimulation to a nerve, and a lead portion having one end connected to the stimulation electrode;
A stimulation generator that is connected to the other end of the lead portion and generates a nerve stimulation signal for applying the electrical stimulation;
A test stimulus input unit that is operated to cause the stimulus generator to generate a test stimulus signal for specifying an indwelling position of the stimulus electrode;
With
The nerve stimulation apparatus, wherein input to the test stimulus input unit is stopped when a predetermined time elapses after the test stimulus input unit is operated.   The nerve stimulation apparatus according to claim 1, wherein input to the test stimulus input unit is stopped immediately after the test stimulus input unit is operated.   The nerve stimulation apparatus according to claim 1, wherein the test stimulus input unit is provided in the lead unit.   The nerve stimulation device according to claim 1, wherein the test stimulus input unit is detachably provided on the stimulus generation device.   The nerve stimulation device according to claim 1 or 2, wherein the stimulation generation device receives an input to the test stimulation input unit only when an indwelling operation of the nerve stimulation electrode is performed. A tubular member that is inserted into the living body and through which the nerve stimulation electrode is inserted when the stimulation electrode is placed;
The nerve stimulation device according to claim 5, wherein the stimulation generator receives an input to the test stimulation input unit only when the nerve stimulation electrode is inserted through the tubular member. A stylet that is inserted into the lead portion when the stimulation electrode is placed;
The nerve stimulation device according to claim 5, wherein the stimulation generator receives an input to the test stimulation input unit only when the stylet is inserted into the lead unit.

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