RU2269291C1 - Method and device for assessing sensory sensitivity under anesthesia conditions - Google Patents

Abstract

FIELD: medicine; medical engineering.

SUBSTANCE: method involves acting with stimulus like electric current pulses applied to patient skin via electrodes on one or several patient body regions and fixing response to the stimulus by recording galvanic skin reflex response on skin areas not exposed earlier to stimulus action. The response being available, retained sensory sensitivity conclusions are to be drawn. Sensory and pain sensitivity are determined in advance without anesthesia on every patient skin region, to which electric current pulses are to be applied, by questioning the patient and individual electric current sensory and pain sensitivity thresholds corresponding to them and to each stimulating electrode. Electric current pulse amplitude is selected in an interval above the sensory threshold and below the pain sensitivity threshold. Galvanic skin reflex is considered to be response to the stimulus when recording it during time interval not exceeding 10 s after having sent the stimulus. The device has electrode group for producing stimulating pulses and transducers for reading physiologic responses with appropriate electrodes connected to control and recording unit having indicator display. The electrodes for producing the stimulating pulses are pairwise connected to each other and to control and recording unit pulse oscillator. Outputs of pulse oscillator control unit are connected to the first control input of the pulse oscillator and one of galvanic skin reflex signal detection unit inputs, output of unit for measuring electric resistance being connected to the other input. The output is connected with its input to the galvanic skin reflex signal detection unit electrodes. Galvanic skin reflex signal detection unit outputs are connected to the second control input of the pulse oscillator and to indicator display. Galvanic skin reflex signal detection unit input/output is connected to computer interface unit.

EFFECT: high reliability of measurement data; optimum time for recording galvanic skin reflex signals.

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Description

The invention relates to medicine, namely to anesthesiology, and can be used for various surgical procedures requiring general anesthesia.

Objectification of the adequacy of the components of anesthesiology benefits is one of the priority tasks of anesthesiology. Widely used in clinical practice, the assessment of such components of anesthesia as consciousness, analgesia, neurovegetative inhibition is based on indirect criteria (change in hemodynamic parameters, assessment of the skin condition, pupil size, lacrimation, etc.), does not guarantee the objectivity of the information received, safety and comfort operated patient. The methods of processing the native electroencephalogram (SEF 90%, BIS, INEEG, AER) allow a certain degree of objectivity to control the level of consciousness, and the use of cardiointervalography and stimulation myography - to ensure the adequacy of the assessment of vegetative status and muscle relaxation.

However, sensory sensitivity, primarily pain sensitivity, is practically not monitored during anesthesia, while its clinical significance, especially with regional blockade, is extremely high. Sensitivity assessment is limited by the subjective “pin prick” criterion - tingling with a needle in areas of possible regional block spread and patient assessment of the severity of pain according to (acute - dull - no sensations) (see, for example, Lanz E., et al. Extent of blockade following various techniques of brachial plexus block. // Anesth. Analg., 1983, V.62, No. 1, p. 55-61). The method does not allow assessing the depth of sensory blockade in patients with altered levels of consciousness, and some patients may agrave or experience allodynia, which distorts the assessment of the data obtained.

The possibility of using a monosynaptic H-reflex in stimulating myography to objectify the dynamics of the development of regional blockade is known (see Gnezdilov A.V. Diagnosis and treatment of phantom and vertebrogenic pain syndromes // Diss. Doctor of Medical Sciences, Moscow, 1999). The method provides fairly objective information about the development of the depth of the sensory block and the relief of pain, but it requires stable conditions when registering a myographic response and the appearance of various “tips” in connection with this. In addition, the method is applicable to assess the development of sensory blockade only on the lower extremities.

The use of somatosensory evoked potentials is also not widespread due to the difficulty of implementing this technique in an operating room (see Zhenilo V.M. et al. Computer analysis of some components of general anesthesia // Anesthesiology and Intensive Care, No. 3, 2001, p.6- 8). In addition, using this method, it is possible to evaluate only the severity of analgesia.

There are also patent publications. Thus, it is known to provide sound stimuli to a patient under anesthesia and record the response by means of electrodes mounted on the head. The effectiveness of anesthesia is analyzed by the amplitude-frequency characteristics of the electrical signal, using adaptive digital processing (US 5891050, April 6, 1999). In the invention EP 1273265, 01/08/2003 describes a method for monitoring the parameters of cardiovascular activity.

A known method and device for monitoring and / or control of the neuromuscular block during anesthesia (EP 0787506, 08/06/1997). The method consists in exposure to a stimulus - an electrical impulse of myostimulation and recording the response to this stimulus by measuring the cuff pressure of a standard tonometer to monitor the neuromuscular block. The device contains means for generating a stimulus — an electric pulse generator of myostimulation and means for measuring the cuff pressure of a standard tonometer, as well as means for monitoring the neuromuscular block. However, from the analysis of the invention it cannot be concluded that in the process of anesthesia with regional blockade, it is possible to control sensory sensitivity. It is known, however, that a skin-galvanic reaction (RAG) is a component of the orientational reflex to various stimuli, and RAG can be recorded using a conventional electroencephalograph (see Osipova N.A. Assessment of the effect of narcotic, analgesic and psychotropic drugs in clinical anesthesiology. L. , Medicine, 1988, p. 48-51).

The closest in technical essence and combination of features to the patented group of inventions are a method and apparatus for assessing sensory sensitivity in anesthesia (US 4570640, 02/18/1986). A stimulus in the form of electric current pulses is applied to the patient’s skin by means of electrodes on one or more parts of the patient’s body and the response to the stimulus is recorded by electrodes recording the patient’s skin-galvanic reaction on parts of the body not exposed to the stimulus, by the presence of which it is judged that sensory sensitivity is maintained. A device for assessing sensory sensitivity under anesthesia contains a group of electrodes for supplying stimulating pulses and physiological reaction sensors with corresponding electrodes connected to a control and recording unit, including an indicator.

The technical result of the inventions is to increase the reliability of determining sensory sensitivity by taking into account individual thresholds of a stimulating effect and optimizing the time of recording a skin-galvanic reaction. An additional technical result is the ability to assess the patient's psychoemotional state, including under general anesthesia.

The technical result is achieved by the fact that the method of assessing sensory sensitivity under anesthesia consists in the action of a stimulus in the form of electric current pulses applied to the patient’s skin by means of electrodes on one or more parts of the patient’s body and recording the response to the stimulus by recording electrodes of the patient’s skin-galvanic reaction in areas of the body that were not exposed to the stimulus, by the presence of which they are judged to maintain sensory sensitivity. Previously, in the absence of anesthesia, for each area of the patient’s skin to which electric current impulses are applied, sensory and pain sensitivity are determined by interrogating the patient, and the corresponding individual sensory and pain thresholds of current for each stimulating electrode. In this case, the amplitude of the electric current pulse is chosen in the range above the sensory threshold and below the threshold of pain sensitivity, and the skin-galvanic reaction is considered a response to the stimulus when it is recorded for a time not exceeding 10 s after the stimulus is applied.

A device for assessing sensory sensitivity under anesthesia contains a group of electrodes for supplying stimulating pulses and physiological reaction sensors with corresponding electrodes connected to a control and recording unit, including an indicator. The electrodes for supplying stimulating pulses are connected in pairs and connected to the pulse generator of the control and registration unit, while the outputs of the control unit of the pulse generator are connected to the first control input of the pulse generator and one of the inputs of the skin-galvanic response signal isolation unit, the output of the unit is connected to the other input measuring the electrical resistance connected by the input to the electrodes of the sensor of the skin-galvanic reaction, the outputs of the signal isolation block of the skin-galvanic p The reactions are connected to the second control input of the pulse generator and the indicator, and the input-output of the skin-galvanic response signal isolation unit is connected to the computer interface unit.

RAG can be recorded in response to irritation of segments of the human body (visceral evoked potentials), which can be reversibly denervated by applying various regional blockades using local anesthetics. After the regional blockade is completed, the corresponding segments of the human body are stimulated with electric current, the voltage of which is preliminarily selected before the operation by determining pain thresholds. The development of sensory blockade corresponds to the disappearance of the skin-galvanic reaction in response to electrical irritation. The advantages of this technique include the ability to determine the development of sensory block in patients with a reduced level of consciousness. This, in turn, allows patients to be sedated before a regional blockade is performed, which reduces the severity of psychoemotional stress. Studies have shown that a skin-galvanic reaction recorded in a specified time range in response to electrical irritation of human body segments exposed to regional blockade serves as a reliable criterion for the development of depth of the sensory block.

The invention is illustrated in the drawings, where:

figure 1 presents a block diagram of a device;

figure 2 - algorithm for assessing sensory sensitivity;

figure 3 is a diagram of a dermatome for clinical examples.

A device for implementing the method includes a patch element 10 containing one or more pairs of electrodes 11 for supplying stimulating pulses of electric current to the skin (stimulating electrodes). Element 10 has means of attachment to the patient’s body (not shown in the figure), and electrodes 11 have means for providing galvanic contact with the skin. The electrodes 11 can be applied to the patient’s skin without using a separate patch element 10, for example, using individual fastening means.

The electrodes 11 are connected to the control and registration unit 12. Block 12 contains a controllable generator of electric current pulses 14, the control input of which is connected to the generator control unit 16. The generator 14 has outputs according to the number of electrodes used 11. The generator control unit 16 has means for individually adjusting the parameters of stimulating pulses supplied to each of the pairs of electrodes 11.

The sensor 18 RAG represents two electrodes with means of attachment to the skin of the patient in parts of the human body that are not exposed to blockade. The sensor 18 is connected to the block 20 for measuring the electrical resistance between the electrodes of the said sensor 18. The block 20 is connected with the output of the RAG signal extraction unit 22, and the outputs of the block 22, in turn, are connected to the inputs of the indicator 24 and the generator 14. The control input 22 is connected to another output of the control unit 16. The input-output of the block 22 is connected to the output-input of the block 26 of the interface with the computer. Block 12 includes a power supply 28, made according to medical safety standards and providing all the necessary voltages for the operation of block 12. Block RGR signal isolation 22 is implemented based on established criteria (RU 2107430).

The implementation of the method when monitoring the development of the blockade in the conditions of regional anesthesia is illustrated by the example of a device, the algorithm of which is presented in figure 2.

Before starting work, the electrodes 11 are installed in the blockade zone, and the RAG sensor 18 is placed on a portion of the patient’s body that is not subject to blockade.

At the stage of preparing the patient for surgery, individual sensory and pain sensitivities of the skin under the electrodes 11 in the blockade region are determined in accordance with the algorithm. To do this, sequentially for each pair of stimulating electrodes 11 from the pulse generator 14 serves gradually increasing in magnitude pulses of electric current. Sensitivity thresholds are determined by questioning the patient. For each pair of stimulating electrodes, an individual sensory and pain thresholds of the current are established and fixed by pressing the corresponding button in the control unit 16. The fixed values are stored in the generator control unit 16 (operation “Saving and displaying the touch threshold for this channel”).

At the same time, block 20 records the electrical resistance of the skin, measured by the sensor 18, and in block 22, the RGR signals are extracted. In the absence of blockade, RAG signals must accompany each stimulation pulse, the amplitude of which satisfies the condition: it is higher than the sensory threshold, but lower than the threshold of pain sensitivity.

During anesthesia, skin sensitivity is checked in those areas where electrodes 11 are applied, the location of which is fixed. For the convenience of measurements, it is possible to supply pulses sequentially to individual electrodes of the group, that is, to provide scanning — a matrix of stimulators with sequential stimulation is formed.

Check the development of the blockade is carried out automatically in accordance with the algorithm embedded in the control unit 16 (operation "Is there a RGR?" In figure 2). The absence of RAG for 10 s in response to stimulation clearly indicates the development of blockade in the area of the body subjected to stimulation. RAG waiting time was selected based on the results of statistical processing of the time of the psychophysiological response to stimulation and RGR waveforms, the duration of which does not exceed 10 s in 99.9% of cases.

A patented device can be used to control the adequacy of anesthesia in a surgical setting. In this case, carry out a simple monitoring of the RGR signals and their calculation (operation "Measurement and calculation of the RGR" in figure 2). If the number of RAG signals does not exceed 5 units in 5 minutes, this will indicate that the patient is in a state of psycho-emotional comfort. This criterion is average and verified by the standard clinical features used by anesthesiologists when conducting anesthesiological aids.

Clinical example 1. Patient G., 34 years old, was treated at the Russian Scientific Center of Medical Sciences for "chronic venous insufficiency; varicose veins of the lower extremities. " Linton's operation was performed under balanced anesthesia based on spinal - epidural block. The risk of anesthesia I Art. by ASA.

The patient was taken to the operating room after premedication of S. Dormici 0.1 mg / kg. The level of consciousness is passive wakefulness according to V.A. Svetlov et al. Non-invasive monitoring (Harvard standard) was established - ECG (sinus rhythm), blood pressure (110/60 mmHg), heart rate (82 per min ^-1 ), SpO ₂ (99%), t _p - (32.6 ° C). Begin infusion of solutions of 6 ml / kg / h. To assess the level of consciousness, EEG according to Berg-Fourier was used. SEF 90% (24 Hz) was directly determined. EEG electrodes are installed in the lead F - T. To assess psycho-emotional comfort, electrodes were installed to register the RAG on the index and ring fingers of the right hand. 16 RAGs were recorded in 5 minutes, which, in accordance with the established criterion, was regarded as psycho-emotional stress. Sensory and pain thresholds on the upper limbs were determined according to Abramov Yu.I. (4 mA is the sensory threshold, 16 mA is the pain threshold, respectively, for the lower extremities; 8 mA is the sensory threshold, 24 mA is the pain threshold, respectively, for both limbs). To confirm the data obtained using RAG in response to stimulation, we used a pin prick sensitivity assessment. No anesthesia and analgesia zones have been obtained. In order to reduce psycho-emotional discomfort in / in, S. Dormici 0.05 mg / kg was introduced. ECG - sinus rhythm, blood pressure - 120/90 mmHg, heart rate - 72 min ^-1 , SpO ₂ - 99%, t _p + 32.3 ° С, level of consciousness - nap (SEF 90% - 16.25 Hz). The number of RAGs was 3 in 5 min in the absence of stimulation, which indicates the preservation of the indicative reaction. Spinal-epidural block was made at the level of L ₃ - L ₄ , on the first attempt, without technical difficulties. The epidural catheter is 5 cm cranial. 15 mg of S. Marcaini 0.5% was administered subarachnoidly. To exclude the appearance of a tentative reaction of RAG to irritations, S. Dormici 0.05 mg / kg was additionally administered iv. 5 minutes after the onset of subarachnoid anesthesia and deepening sedation, hemodynamics did not undergo significant changes, the level of consciousness was superficial sleep (SEF 90% - 15 Hz). RAG alone - not determined.

Testing of skin dermatomas (see Fig. 3) by stimulation with electric impulses, which corresponded to the previously established sensory and pain thresholds of the lower extremities, began. There was a lack of RAG response to stimulation of L ₅ - S ₁ dermatomes, which indicates the development of sensory blockade. In L ₄ - T _x dermatomes, a single RAG was noted, indicating the presence of analgesia. Above T _x, multiple RAG was noted (the first signal was recorded within 10 seconds after stimulation and then 2-4 RAG in 1 min), which indicates the absence of sensory blockade of these regions. Hemodynamic parameters did not change. The aforementioned RAG stimulation is fully confirmed by the pin prick method. Sensitivity assessment was carried out immediately after determination of stimulation samples and patient awakening.

After the initial sensitivity assessment, S. Dormici 0.05 mg / kg was additionally administered, and after 10 min, sensory sensitivity was repeated for skin dermatomas. The absence of RAG on stimulation in dermatomes from S _II to T _{x was} noted, which was characterized as the presence of sensory blockade. Above T _x, RAG was noted, indicating the absence of sensory blockade. The data of sensory sensitivity analysis by RAG in response to electrical stimulation were fully confirmed by the pin prick method after the patient was awakened.

In the future, the pain and motor reaction to the skin incision in the patient was not noted. Blood pressure - 110/60 mmHg, heart rate - 64 min ^-1, SpO ₂ - 99%, t _n + 32,3 ° C, level of consciousness - nap (SEF 90% - 18.1 Hz), RAG - not determined nor alone, nor on electrical stimulation.

The course of surgery without features. However, despite the sedation of S. Propofoli 1 mg / kg / h, 1.5 hours after the start of anesthesia, the patient showed the appearance of spontaneous single RAGs up to 8 in 5 minutes. At the same time, the level of drug depression of consciousness was assessed as superficial (SEF 90% - 12.2-14 Hz) and deep (SEF 90% - 10.3-11.1 Hz) sleep. Upon waking up (SEF 90% 20.2 Hz), the patient noted discomfort in the elbow bends, especially in the area of standing of the peripheral venous catheter, as well as in places of close contact with the operating table, that is, the development of positional discomfort (PD) II tbsp. by V.A. Svetlov et al. No significant hemodynamic changes were noted. There was no pain reaction or discomfort in the area of surgical intervention.

This clinical symptomatology led to an increase in the dose of sedatives S. Propofoli 2 mg / kg / h, S. Diazepami 0.15 mg / kg / h, which for some time led to the disappearance of RAG. The level of drug depression of consciousness was assessed as superficial (SEF 90% - 12.2-14 Hz) and deep (SEF 90% - 10.3-11.1 Hz) sleep.

2.5 hours after the start of anesthesia, the patient developed frequent RAG, more than 10 in 5 minutes, with the same level of depression of consciousness without significant changes in hemodynamics. Upon waking up, the patient independently complained of pain in the standing area of the peripheral venous catheter and in areas of the body that were in close contact with the operating table, paresthesia in the elbow joints (PD - III-IV art.). This required the use of S. Phentanyli 0.03 mcg / kg / h, and then an increase in doses of S. Propofoli to 4 mg / kg / h, S. Diazepami 0.2 mg / kg / h. Despite the high level of drug-induced depression of consciousness - deep sleep (SEF 90% - 10-11.4 Hz), RAG (up to 16-18 in 5 min) was noted, which disappeared after the introduction of S. Phentanyli and S. Diazepami for 10-15 min There was no pain reaction or discomfort in the area of surgical intervention.

3.5 hours after the start of anesthesia, the surgery was over. The patient regained consciousness 10 minutes after the end of the S. Propofoli infusion. On awakening, marked pain was observed in the elbow bends and shoulder blades. When assessing sensory blockade by the pin prick method, anesthesia from S _II to T _{IX was} detected.

Clinical example 2. Patient R., 42 years old, was undergoing treatment at the Russian Scientific Center of Medical Sciences for "rupture of the meniscus of the right knee joint." The risk of anesthesia I Art. by ASA.

The patient was taken to the operating room after premedication of S. Dormici 0.1 mg / kg. The level of consciousness is passive wakefulness. ECG (sinus rhythm), blood pressure (130/90 mmHg), heart rate (96 rpm ^-1 ), SpO ₂ (99%), t _p (33.1 ° C). Begin infusion of solutions of 6 ml / kg / h. SEF 90% (26 Hz). To assess psycho-emotional comfort, electrodes were installed to register RAG on the index and ring fingers of the right hand (12 RGR in 5 min), which is regarded as psycho-emotional stress. Sensory and pain thresholds on the upper extremities were determined (8 mA - sensory threshold, 34 mA - pain threshold, respectively). In the future, the sensory and pain thresholds for the lower extremities are determined (12 mA is the sensory threshold, 44 mA is the pain threshold, respectively, for both limbs). When assessing sensitivity using the pin prick method and using RAG, no anesthesia and analgesia zones were obtained. Sedation of S. Dormici 0.05 mg / kg started. ECG - sinus rhythm, blood pressure - 120/70 mmHg, heart rate - 88 min ^-1 , SpO ₂ - 98%, t _p + 32.8 ° С, level of consciousness - nap (SEF 90% - 18.1 Hz), the amount of RAG - 4 for 5 min - approximate reaction. Spinal-epidural block was made at the level of L ₃ - L ₄ , on the first attempt, without technical difficulties. 15 mg of S. Marcaini 0.5% was administered subarachnoidly. Additionally, S. Dormici 0.05 mg / kg was administered iv. 5 minutes after the onset of subarachnoid anesthesia and deepening sedation, hemodynamic indicators without significant dynamics, the level of consciousness - superficial sleep (SEF 90% - 14.1 Hz), RAG at rest - is not determined.

Skin dermatome testing started. There was a lack of RAG response to the stimulation of S ₂ - S ₁ dermatomes, which indicates the development of sensory blockade. In the L _V dermatome, a single RAG was observed in response to irritation, indicating the presence of analgesia. Above L _V, multiple RAG was observed (3-4 in 1 min), which indicates the absence of sensory blockade of these areas. Hemodynamic parameters did not change. RAG data for stimulation is fully confirmed by the pin prick method. In this case, the sensitivity assessment was carried out immediately after the determination of stimulation samples and the patient's awakening.

After 20 minutes, the state of the sensory block did not change, which required a switch to general anesthesia with mechanical ventilation.

Clinical example 3. Patient R., 37 years old, was undergoing treatment at the Russian Scientific Center of Medical Sciences for “Secondary radicular syndrome. "Hernia of the intervertebral disc at the level of L _III - L _IV - L _V against the background of osteochondrosis of the spine." The risk of anesthesia I Art. by ASA.

The patient was taken to the operating room after premedication of S. Dormici 0.1 mg / kg to perform microdisectomy. The level of consciousness is stunning. ECG - sinus rhythm, blood pressure - 100/70 mmHg, heart rate - 68 min ^-1 , SpO ₂ - 97%, t _p - 33.6 ° С. Started infusion of crystalloid solutions of 6 ml / kg / h. SEF 90% (18.1 Hz) - stunning, 2 RAG for 5 min - approximate reaction. Sensory and pain thresholds on the upper extremities were determined (6 mA - sensory threshold, 38 mA - pain threshold, respectively). Initial anesthesia started: S. Propofoli 2 mg / kg, S. Phentanyli 6 mcg / kg. ECG - sinus rhythm, blood pressure - 90/50 mmHg, heart rate - 58 beats ^-1 , SpO ₂ - 98%, t _p + 33.9 ° C, level of consciousness - deep sleep (SEF 90% - 11 Hz), RAG - not determined. Electrical stimulation of the upper extremities was performed - no RAG response was received. Performed tracheal intubation with tube No. 9 on the first attempt, without technical difficulties. HELL - 110/70 mmHg, heart rate - 65 rpm ^-1 , SpO ₂ - 99%, t _p + 33.7 ° C, level of consciousness - deep sleep (SEF 90% - 11 Hz), RAG - not determined, which indicates the absence of a reflex and autonomic reaction.

Maintenance of anesthesia: enflurane 0.5-1.5 MAC, S. Phentanyli - 4-8 mcg / kg / h. Until the main stage of surgical intervention, the course of anesthesia is unremarkable. When a hernia of the disc was removed at the level of L _IV - L _V , RAG suddenly appeared in the patient - up to 18 in 5 minutes. After 5 min, arterial hypertension (BP 140/100 mmHg) and an increase in heart rate (up to 86 per min ^-1 ) occurred, which indicates the inadequacy of the analgesic component of anesthesia. At the same time, the level of drug depression of consciousness remained no higher than surface sleep (SEF 90% no higher than 16 Hz). An increase in enflurane inhalation to 2 MAC and administration of S. Phentanyli to 12 mcg / kg / h led to stabilization of hemodynamic parameters (blood pressure 110/80 mmHg, heart rate up to 74 per min ^-1 ), but the number of RAG remained high - 10-12 for 5 min The level of drug depression of consciousness remained at the level of deep sleep (SEF 90% not higher than 12 Hz). The introduction of S. Dormici 0.07 mg / kg led to a short-term disappearance of RAG for 5-10 minutes. The complete disappearance of RAG occurred only after the end of the main stage of the operation and the termination of trauma to the roots of the spinal cord.

Claims (2)

1. A method for assessing sensory sensitivity under anesthesia, consisting in the action of a stimulus in the form of electric current pulses applied to the patient’s skin through electrodes on one or more parts of the patient’s body and recording the response to the stimulus by recording electrodes of the patient’s skin-galvanic reaction on the body’s parts not exposed to the stimulus, by the presence of which it is judged to maintain sensory sensitivity, characterized in that previously in the absence of anesthesia for each site the patient’s skin, to which electric current impulses are applied, determine sensory and pain sensitivity by interrogating the patient and the corresponding individual touch and pain thresholds of current for each stimulating electrode, while the amplitude of the electric current pulse is chosen in the range above the sensory threshold and below the pain sensitivity threshold, and the skin-galvanic reaction is considered a response to the stimulus when it is registered for a time not exceeding 10 s after the stimulus is applied. 2. A device for assessing sensory sensitivity under anesthesia, containing a group of electrodes for supplying stimulating pulses and physiological reaction sensors with corresponding electrodes connected to a control and recording unit, including an indicator, characterized in that the electrodes for supplying stimulating pulses are paired and connected to the pulse generator of the control unit and registration, while the outputs of the control unit of the pulse generator are connected to the first control input of the generator pulses and one of the inputs of the skin-galvanic reaction signal extraction unit, to the other input of which the output of the electrical resistance measuring unit is connected, connected to the input with the electrodes of the skin-galvanic reaction sensor, the outputs of the skin-galvanic reaction signal extraction unit are connected to the second control input of the pulse generator and indicator, and the input-output of the unit for extracting signals of the skin-galvanic reaction is connected to the unit for interfacing with a computer.

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