Closed-loop transcranial stimulation system and method

Abstract

The invention discloses a closed-loop transcranial stimulation system and a closed-loop transcranial stimulation method. 0.3 mg of scopolamine and 3 mg of midazolam are intramuscularly injected before an operation; after a patient enters a room, sufentanil is subjected to intravenous injection induced by right subclavian vein and radial artery puncture general anesthesia, propofol is subjected to target-control infusion, the plasma target concentration is 3.0 mu g / mL, vecuronium bromide is 0.15 mg / kg, tracheal intubation is performed after 5 min, general anesthesia maintains target-control infusion of propofol, and after the patient enters the room, the target-control infusion of propofol is performed. A TMS stimulation coil electricity-magnetism-heat-stress model, a single-phase and double-phase pulse discharge circuit model and a neuron dynamic response model under the action of a TMS are established, and the influence of TMS system parameters on space-time distribution characteristics of an intracranial induced electric field and neuron membrane potential can be accurately expressed. Behavior perception and system auditory stimulation are combined to be applied to nursing intervention of severe craniocerebral injury coma patients, self-repairing and consciousness awakening of the brain functions of the patients can be effectively promoted, and meanwhile recovery of limb functions and daily life ability of the patients is facilitated.

Description

Technical Field

[0001] This invention relates to the field of cranial stimulation technology, specifically to a closed-loop transcranial stimulation system and method. Background Technology

[0002] In recent years, the mortality rate of stroke has been declining. Stroke survivors often experience various types of functional impairments. Among these patients, about 65% will have residual upper limb motor impairments. Sensory impairment is also one of the most common symptoms in stroke patients. After a stroke, 31% to 89% of patients will have varying degrees of sensory impairment. This not only has an adverse effect on the recovery of the patient's motor function, but also has an adverse effect on the patient's daily life activities and their mental health.

[0003] The "central-peripheral-central" closed-loop rehabilitation theory refers to the full use of two major treatment methods, "central intervention" and "peripheral intervention," to treat patients. Its core lies in the combination of central and peripheral interventions, forming a positive feedback loop. The closed-loop rehabilitation model refers to improving neural plasticity through central pre-activation, and then combining it with peripheral stimulation to enhance the remodeling ability of function, thereby promoting the functional recovery of the central nervous system.

[0004] Studies have shown that ischemia and hypoxia after brain tissue injury hinder energy metabolism. Hypoxia in brain cells leads to increased anaerobic glycolysis, producing large amounts of lactic acid. Acidosis causes the release of iron ions, and the highly toxic oxygen free radicals formed by iron ions as catalysts aggravate brain damage. In order to reduce the "secondary damage" caused by tissue ischemia and hypoxia in the early stage of traumatic brain injury as early as possible and to address the closed loop of cranial stimulation, this invention proposes a closed loop cranial stimulation system and method. Summary of the Invention

[0005] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide a closed-loop transcranial brain stimulation system and method.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a closed-loop transcranial stimulation system and method, wherein the patient is given an intramuscular injection of scopolamine 0.3 mg and midazolam 3 mg before surgery; after the patient enters the operating room, general anesthesia is induced by puncture of the right subclavian vein and radial artery, followed by intravenous injection of sufentanil 0.2 μg / kg, propofol target-controlled infusion at a plasma target concentration of 3.0 μg / mL, and vecuronium bromide 0.15 mg / kg. After 5 minutes, endotracheal intubation is performed, and propofol is maintained by target-controlled infusion at a plasma target concentration of 2.0 μg / mL, sufentanil is infused at a constant rate of 0.3 μg / (kg·h), and vecuronium bromide is intermittently added at 0.05 mg / kg. The intraoperative ventilation parameters are a tidal volume of 10 mL / kg, a respiratory rate of 12 breaths / min, and an end-tidal CO2 partial pressure (P0.05). EFCO2 was maintained between 28-30 mmHg, and medication was administered using a Jasby 3500 infusion pump according to the Marsh protocol. However, in the closed-loop group, the infusion pump and monitor were connected in a closed loop with a set feedback value of BIS=50. When the intraoperative blood pressure dropped to systolic pressure <80 mmHg, ephedrine 5 mg was administered intravenously; when the heart rate was <50 beats / min, atropine 0.2 mg was administered intravenously.

[0007] The TMS closed-loop control method based on neuronal dynamic response can target the stimulation parameters according to feedback variables, thereby changing the neuronal membrane potential. Different neurons have different threshold values, and the threshold change pattern is related to the neuronal state. The neuronal dynamic threshold prediction model in the LIFDT model is as follows:

[0008]

[0009] The dynamic threshold model represents the neuron firing threshold V after each stimulus. th The neuron's firing adaptability is reflected by the jump decay pattern, where the neuron threshold increases at the instant of the nth stimulus and gradually decays from its maximum value with a time constant τA before the (n+1)th stimulus. The adaptive time constant τA = 100ms and ΔV = 2mV.

[0010] Preferably, the neural electrical stimulation may promote awakening by altering the levels of neurotransmitters in the body. The amount of dopamine levels in comatose patients before stimulation and the increase after stimulation are related to the improvement of consciousness. Patients with low dopamine levels before stimulation showed a significant increase in dopamine levels after stimulation, and their probability of awakening was higher than that of patients with normal or higher-than-normal dopamine levels before treatment. When bilateral median nerve electrical stimulation was added to conventional comprehensive treatment for comatose patients after traumatic brain injury, the stimulation group had a shorter coma time, faster recovery of consciousness, and a better prognosis than the control group. By measuring the β-endorphin content in cerebrospinal fluid before and after stimulation, it was found that the β-endorphin content in the stimulation group was significantly lower than that in the control group. This suggests that the awakening effect of median nerve electrical stimulation on comatose patients after traumatic brain injury may be due to its inhibition of β-endorphin release in acute comatose patients, reversing its inhibition and damage to the central nervous system, effectively inhibiting intracranial pressure, reducing cerebral edema, and preventing the degeneration of neurons and glial cells.

[0011] Preferably, the nurses will periodically stimulate the patient's hearing with sounds, such as clapping or whistling near the patient's ear, for about 15 seconds each time, and record the patient's response and physiological parameters. For responsive patients, the nurses can use methods such as repeated calling or repeated instructions to strengthen the patient's nerve reflexes. Under the guidance and supervision of the nurses, certain skin cleaning work should be done, such as washing the face and feet with hot water in the morning and evening, and applying lotion to the whole body. At the same time, the nurses should help the patient change positions at certain times, and massage the patient's limbs, from the joints of the two upper limbs to the joints of the two lower limbs, for about 20 minutes. To prevent problems such as venous thrombosis caused by prolonged bed rest, the patient can take medication twice a day. At the same time, a soft brush can be used on the patient's extremities every day, and the patient's family members should be instructed to touch the sensitive areas of the patient's head and earlobes multiple times. The nurses can conduct initial physical function training, passively moving the joints of the limbs five times a day, for about 20 minutes each time.

[0012] Preferably, the behavioral sensory stimulation mainly enhances the activity of the patient's cerebral cortex cells by stimulating the skin, light perception, movement, and temperature perception, while also improving blood circulation, accelerating the patient's awakening, and restoring consciousness as quickly as possible. Systematic auditory stimulation, on the other hand, uses sound waves generated by speech information to stimulate the ascending brainstem, strengthening the patient's physiological activities and neural responses. This allows the patient's brain and consciousness to be efficiently stimulated, which is beneficial for the recovery of the injury. The combination of behavioral sensory stimulation and systematic auditory stimulation has a good clinical effect in stimulating the awakening of patients with severe traumatic brain injury and coma, and can, to some extent, improve the patient's quality of life, help the patient's self-recovery of neural function, improve the patient's state of consciousness, and thus accelerate the patient's awakening.

[0013] Preferably, the elbow joint position sense error is used to assess the patient's sensory function before and after treatment. Brain-computer interface combined with peripheral FES can more effectively improve the position sense of the upper limb elbow joint in stroke patients than peripheral FES alone. Brain-computer interface-based motor rehabilitation may improve the patient's sensory function. The efficacy of brain-computer interface combined with peripheral motor task therapy based on sensorimotor rhythm in stroke patients was shown. The results showed that compared with simple motor trial training and peripheral tactile stimulation, the combined training method can more effectively improve the upper limb sensory function of patients.

[0014] Preferably, if the slope of the stimulation current remains unchanged before and after the zero point, a stimulation current pulse cycle can be divided into three segments, namely one current rising edge and two current falling edges; if the slope of the stimulation current changes before and after the zero point, a stimulation current pulse cycle can be divided into four segments, namely two current rising edges and two current falling edges. When N=2, it can provide eight discharge voltage levels, four positive and four negative. It can not only realize the first type of biphasic approximate triangular wave stimulation current, but also generate the second type of biphasic approximate triangular wave stimulation current. The biphasic stimulation current in TMS has two stimulation modes: intracranial anterior-posterior current stimulation mode and intracranial posterior-anterior current stimulation mode.

[0015] Preferably, the glycerol is produced by glycolysis or degradation of glycerophosphate membrane by phosphokinase. An increase in its content indicates lipid metabolism and brain cell membrane damage. In traumatic brain injury, an increase in glycerol content indicates brain cell membrane damage. Therefore, glucose, lactate and glycerol can be specific indicators of traumatic brain injury. The BIS closed-loop targeted infusion of propofol was compared with the traditional propofol sedation method. The results showed that the BIS closed-loop targeted infusion had a better and more stable sedation effect.

[0016] A closed-loop transcranial brain stimulation system and method, comprising the following steps:

[0017] S1: Regularly awaken the patient with speech daily, combining this with localized verbal stimulation, treating the patient as a normal, conscious, and thinking person; continuously call the patient by name and engage in normal communication, such as explaining the purpose of nursing procedures and soothing the patient's discomfort. Pay close attention to the patient's response to sound and assess the degree of response. Repeatedly reinforce the stimulation of the auditory nerve with speech to gradually build a conditioned reflex, thereby achieving the goal of awakening the patient. This helps alleviate the suppression of the respiratory center by the cerebral cortex, effectively strengthening the patient's cough function, enabling the patient to actively clear nasal secretions, thus maintaining airway patency and reducing pneumonia caused by mechanical ventilation.

[0018] S2: To improve the ability of medical staff to assess patients' conscious state by evaluating indicators such as BAEP during treatment, ensure accurate understanding of patients' physiological state, and adopt reasonable and effective mechanical ventilation programs to reduce patients' ventilation time and the occurrence of respiratory complications. Auditory stimulation may cause patients to experience maladaptive stimuli and agitation, such as adverse reactions like patient-ventilator asynchrony.

[0019] S3: By regulating the balance of DLPFC in both cerebral hemispheres through anodic tDCS in the left DLPFC region and cathodic tDCS in the right DLPFC region, the patient's emotional disorders can be effectively improved, thus playing a role in regulating emotions and improving depressive state. Mirror neurons have been proven to play an important role in human imitation learning. Using advanced virtual reality technology, patients can first observe certain daily limb movements and then be asked to actively imitate them, enhancing the patient's "immersion" during the treatment process. This approach helps promote neural plasticity and accelerate the recovery of functional disorders.

[0020] S4: Stimulation begins, the discharge switch is turned on, the energy storage capacitor discharges to the stimulation coil, the stimulation current rises, a time-varying induced magnetic field is generated around the stimulation coil, and an induced electric field is induced on the neuron, causing the neuronal membrane potential to rise. When the neuronal membrane potential reaches the initial discharge threshold Vth(1) = 10mV, the control module provides a turn-off signal to the discharge switch, and the first stimulation ends. Before the second stimulation begins: the initial discharge threshold Vth(1) = 10mV of the neuronal membrane potential is input into the neuronal dynamic threshold prediction model. The discharge threshold Vth increases at the moment of discharge and according to the neuronal dynamic threshold prediction model, (V th (1)+ΔV) is the maximum value, and it gradually decreases from the maximum value with the time constant τA; the voltage detection module extracts the voltage value across the energy storage capacitor and inputs it into the control module. The control module provides a conduction signal to the charging switch S. The charging ends when the voltage across the energy storage capacitor recovers to the preset value.

[0021] S5: Propofol has a strong vasodilatory effect. When TCI is induced, it reaches the set plasma target concentration in a short time, which often leads to hypotension after general anesthesia induction, especially when combined with fentanyl-like drugs. The degree of propofol's effect on the circulatory system is closely related to the time, dosage, and injection rate. At time points such as 3 minutes after anesthesia intubation, 1 hour after cerebral cortex incision, and 1 hour after tumor resection, the patient's blood pressure decreased. The MAP decrease in the closed-loop group was less than that in the target-controlled group. After general anesthesia induction, the patient's BIS decreased rapidly. When the set feedback value (BIS=50) was reached, the feedback regulation of the closed-loop group was activated, and the propofol infusion volume was reduced. Therefore, the MAP change tended to be stable. There was no obvious hypertension reaction during strong stimulation operations such as intubation, skin incision, skull sawing, and skin suturing, indicating that the depth of anesthesia was sufficient for the operation. Throughout the anesthesia process, the closed-loop group could accurately control the depth of anesthesia, reduce intraoperative blood pressure fluctuations, and facilitate brain tissue perfusion.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention establishes an electro-magnetic-thermal-stress model for TMS stimulation coils, a single-phase and dual-phase pulse discharge circuit model, and a dynamic response model of neurons under TMS action. These models can accurately describe the influence of TMS system parameters on the spatiotemporal distribution characteristics of intracranial induced electric fields and neuronal membrane potentials. The auditory stimulation of the behavioral perception combined system is applied to the nursing intervention of patients with severe traumatic brain injury and coma, which can effectively promote the self-repair of patients' brain function and awakening of consciousness. It is also beneficial to the recovery of patients' limb function and daily living abilities. Attached Figure Description

[0024] Figure 1 This is a diagram illustrating the TMS closed-loop circuit of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Please see Figure 1 This invention provides a technical solution: a closed-loop transcranial stimulation system and method. Preoperatively, scopolamine 0.3 mg and midazolam 3 mg are administered intramuscularly. After the patient enters the operating room, general anesthesia is induced by puncture of the right subclavian vein and radial artery, followed by intravenous injection of sufentanil 0.2 μg / kg, target-controlled infusion of propofol (plasma target concentration 3.0 μg / mL), and vecuronium bromide 0.15 mg / kg. Five minutes later, endotracheal intubation is performed, and target-controlled infusion of propofol is maintained during general anesthesia (plasma target concentration 2.0 μg / mL). Sufentanil is infused at a constant rate at 0.3 μg / (kg·h), with intermittent supplemental administration of vecuronium bromide 0.05 mg / kg. Intraoperative ventilation parameters are: tidal volume 10 mL / kg, respiratory rate 12 breaths / min, and end-tidal CO2 partial pressure (P0.05). EF CO2 was maintained between 28-30 mmHg, and medication was administered using a Jasby 3500 infusion pump according to the Marsh protocol. However, in the closed-loop group, the infusion pump and monitor were connected in a closed loop with a set feedback value of BIS=50. When the intraoperative blood pressure dropped to systolic pressure <80 mmHg, ephedrine 5 mg was administered intravenously; when the heart rate was <50 beats / min, atropine 0.2 mg was administered intravenously.

[0027] The TMS closed-loop control method based on neuronal dynamic response can target and adjust stimulus parameters according to feedback variables, thereby changing the neuronal membrane potential. Different neurons have different threshold values, and the threshold variation pattern is related to the neuronal state. The neuronal dynamic threshold prediction model in the LIFDT model is as follows:

[0028]

[0029] The dynamic threshold model represents the neuron firing threshold V after each stimulus. th The neuron's firing adaptability is reflected by the jump decay pattern, i.e., the neuron threshold increases at the instant of the nth stimulus and gradually decays from its maximum value with a time constant τA before the (n+1)th stimulus. The adaptive time constant τA = 100ms and ΔV = 2mV.

[0030] Electrical nerve stimulation may promote awakening by altering neurotransmitter levels in the body. The increase in dopamine levels before and after stimulation in comatose patients is related to the improvement in consciousness. Patients with low dopamine levels before stimulation showed a significant increase in dopamine levels after stimulation, and their probability of awakening was higher than that of patients with normal or higher-than-normal dopamine levels before treatment. In addition to routine comprehensive treatment, bilateral median nerve stimulation was used to treat comatose patients after traumatic brain injury. The stimulation group had shorter coma time, faster recovery of consciousness, and better prognosis than the control group. Measurements of β-endorphin levels in cerebrospinal fluid before and after stimulation revealed a significant decrease in β-endorphin levels in the stimulation group compared to the control group. This suggests that the awakening effect of median nerve stimulation in comatose patients after traumatic brain injury may be due to its inhibition of β-endorphin release in acute comatose patients, reversing its inhibitory and damaging effects on the central nervous system, effectively inhibiting intracranial pressure increases, reducing cerebral edema, and preventing neuronal and glial cell degeneration. Nursing staff may periodically create sounds to encourage patients to awaken. Stimulate the patient's hearing, such as by clapping or whistling near the ear, for about 15 seconds each time, and record the patient's response and physiological parameters. For responsive patients, nurses can use methods such as repeated calling and repeated instructions to strengthen the patient's nerve reflexes. Under the guidance and supervision of nurses, certain skin cleaning work should be done, such as washing the face and feet with hot water in the morning and evening and applying lotion to the whole body. At the same time, help the patient change positions at certain times, and massage the patient's limbs, from the joints of the two upper limbs to the joints of the two lower limbs, for about 20 minutes. To prevent problems such as venous thrombosis caused by prolonged bed rest, the patient can take medication twice a day. At the same time, a soft brush can be used on the extremities of the patient's upper and lower limbs every day, and the patient's family members should be instructed to touch the sensitive areas of the patient's head and earlobes multiple times. Nurses can conduct initial physical function training, passively moving the joints of the limbs 5 times a day, about 20 minutes each time.

[0031] Behavioral sensory stimulation primarily enhances the activity of cerebral cortex cells by stimulating skin, light, motion, and temperature sensations. It also improves blood circulation, accelerates awakening, and promotes faster recovery of consciousness. Systematic auditory stimulation, on the other hand, uses sound waves generated by speech signals to stimulate the ascending brainstem, strengthening physiological activity and neural responses. This allows for efficient activation of the brain and consciousness, promoting recovery. The combination of behavioral sensory and systematic auditory stimulation has shown significant clinical effectiveness in stimulating the awakening of patients with severe traumatic brain injury and coma. This study aims to improve patients' quality of life, help them recover their neurological functions, improve their level of consciousness, and thus accelerate their awakening. Using elbow joint positional error to assess sensory function before and after treatment, the study found that brain-computer interface combined with peripheral femoroesthesia (FES) was more effective than peripheral FES alone in improving upper limb elbow positional sense in stroke patients. Brain-computer interface-based motor rehabilitation may improve patients' sensory function. The study also examined the efficacy of brain-computer interface combined with peripheral motor task therapy based on sensorimotor rhythm in stroke patients. Results showed that, compared to simple motor trial training and peripheral tactile stimulation, the combined training approach was more effective in improving upper limb sensory function.

[0032] If the slope of the stimulation current remains constant before and after the zero-crossing point, a stimulation current pulse cycle can be divided into three segments: one rising edge and two falling edges. If the slope of the stimulation current changes before and after the zero-crossing point, a stimulation current pulse cycle can be divided into four segments: two rising edges and two falling edges. When N=2, it can provide eight discharge voltage levels (four positive and four negative). This not only enables the generation of the first type of biphasic approximate triangular wave stimulation current but also the second type of biphasic approximate triangular wave stimulation current. TMS has two stimulation modes for biphasic stimulation current: intracranial anterior and posterior. In both intracranial current stimulation modes and intracranial anterior current stimulation modes, glycerol is produced by the degradation of glycerophosphate membranes by glycolysis or phosphokinase. An increase in glycerol content indicates lipid metabolism and brain cell membrane damage. In traumatic brain injury, an increase in glycerol content indicates brain cell membrane damage. Therefore, glucose, lactate, and glycerol can be specific indicators of traumatic brain injury. A comparison was made between BIS closed-loop targeted infusion of propofol and traditional propofol sedation methods. The results showed that BIS closed-loop targeted infusion had a better and more stable sedation effect.

[0033] A closed-loop transcranial brain stimulation system and method, comprising the following steps:

[0034] S1: Regularly awaken the patient with speech daily, combining this with localized verbal stimulation, treating the patient as a normal, conscious, and thinking person; continuously call the patient by name and engage in normal communication, such as explaining the purpose of nursing procedures and soothing the patient's discomfort. Pay close attention to the patient's response to sound and assess the degree of response. Repeatedly reinforce the stimulation of the auditory nerve with speech to gradually build a conditioned reflex, thereby achieving the goal of awakening the patient. This helps alleviate the suppression of the respiratory center by the cerebral cortex, effectively strengthening the patient's cough function, enabling the patient to actively clear nasal secretions, thus maintaining airway patency and reducing pneumonia caused by mechanical ventilation.

[0035] S2: To improve the ability of medical staff to assess patients' conscious state by evaluating indicators such as BAEP during treatment, ensure accurate understanding of patients' physiological state, and adopt reasonable and effective mechanical ventilation programs to reduce patients' ventilation time and the occurrence of respiratory complications. Auditory stimulation may cause patients to experience maladaptive stimuli and agitation, such as adverse reactions like patient-ventilator asynchrony.

[0036] S3: By regulating the balance of DLPFC in both cerebral hemispheres through anodic tDCS in the left DLPFC region and cathodic tDCS in the right DLPFC region, the patient's emotional disorders can be effectively improved, thus playing a role in regulating emotions and improving depressive state. Mirror neurons have been proven to play an important role in human imitation learning. Using advanced virtual reality technology, patients can first observe certain daily limb movements and then be asked to actively imitate them, enhancing the patient's "immersion" during the treatment process. This approach helps promote neural plasticity and accelerate the recovery of functional disorders.

[0037] S4: Stimulation begins, the discharge switch is turned on, the energy storage capacitor discharges to the stimulation coil, the stimulation current rises, a time-varying induced magnetic field is generated around the stimulation coil, and an induced electric field is induced on the neuron, causing the neuronal membrane potential to rise. When the neuronal membrane potential reaches the initial discharge threshold Vth(1) = 10mV, the control module provides a turn-off signal to the discharge switch, and the first stimulation ends. Before the second stimulation begins: the initial discharge threshold Vth(1) = 10mV of the neuronal membrane potential is input into the neuronal dynamic threshold prediction model. The discharge threshold Vth increases at the moment of discharge and according to the neuronal dynamic threshold prediction model, (V th (1)+ΔV) is the maximum value, and it gradually decreases from the maximum value with the time constant τA; the voltage detection module extracts the voltage value across the energy storage capacitor and inputs it into the control module. The control module provides a conduction signal to the charging switch S. The charging ends when the voltage across the energy storage capacitor recovers to the preset value.

[0038] S5: Propofol has a strong vasodilatory effect. When TCI is induced, it reaches the set plasma target concentration in a short time, which often leads to hypotension after general anesthesia induction, especially when combined with fentanyl-like drugs. The degree of propofol's effect on the circulatory system is closely related to the time, dosage, and injection rate. At time points such as 3 minutes after anesthesia intubation, 1 hour after cerebral cortex incision, and 1 hour after tumor resection, the patient's blood pressure decreased. The MAP decrease in the closed-loop group was less than that in the target-controlled group. After general anesthesia induction, the patient's BIS decreased rapidly. When the set feedback value (BIS=50) was reached, the feedback regulation of the closed-loop group was activated, and the propofol infusion volume was reduced. Therefore, the MAP change tended to be stable. There was no obvious hypertension reaction during strong stimulation operations such as intubation, skin incision, skull sawing, and skin suturing, indicating that the depth of anesthesia was sufficient for the operation. Throughout the anesthesia process, the closed-loop group could accurately control the depth of anesthesia, reduce intraoperative blood pressure fluctuations, and facilitate brain tissue perfusion.

[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A closed-loop transcranial brain stimulation system and method, characterized in that: The patient was given an intramuscular injection of scopolamine 0.3 mg and midazolam 3 mg preoperatively. After entering the operating room, general anesthesia was induced by puncture of the right subclavian vein and radial artery, followed by intravenous injection of sufentanil 0.2 μg / kg, propofol target-controlled infusion (plasma target concentration 3.0 μg / mL), and vecuronium bromide 0.15 mg / kg. Five minutes later, endotracheal intubation was performed, and propofol was maintained under target-controlled infusion at a plasma target concentration of 2.0 μg / mL. Sufentanil was administered intravenously at a constant rate of 0.3 μg / (kg·h), with intermittent supplemental administration of vecuronium bromide 0.05 mg / kg. Intraoperative ventilation parameters were: tidal volume 10 mL / kg, respiratory rate 12 breaths / min, and end-tidal CO2 partial pressure (P0.05). EF CO2 was maintained between 28-30 mmHg, and medication was administered using a Jasby 3500 infusion pump according to the Marsh protocol. However, in the closed-loop group, the infusion pump and monitor were connected in a closed loop with a set feedback value of BIS=50. When the intraoperative blood pressure dropped to systolic pressure <80 mmHg, ephedrine 5 mg was administered intravenously; when the heart rate was <50 beats / min, atropine 0.2 mg was administered intravenously. The TMS closed-loop control method based on neuronal dynamic response can target the stimulation parameters according to feedback variables, thereby changing the neuronal membrane potential. Different neurons have different threshold values, and the threshold change pattern is related to the neuronal state. The neuronal dynamic threshold prediction model in the LIFDT model is as follows: The dynamic threshold model represents the neuron firing threshold V after each stimulus. th The neuron's firing adaptability is reflected by the jump decay pattern, where the neuron threshold increases at the instant of the nth stimulus and gradually decays from its maximum value with a time constant τA before the (n+1)th stimulus. The adaptive time constant τA = 100ms and ΔV = 2mV. A closed-loop transcranial brain stimulation system and method, comprising the following steps: S1: Regularly awaken the patient with speech daily, combining this with localized verbal stimulation, treating the patient as a normal, conscious, and thinking person; continuously call the patient by name and engage in normal communication, such as explaining the purpose of nursing procedures and soothing the patient's discomfort. Pay close attention to the patient's response to sound and assess the degree of response. Repeatedly reinforce the stimulation of the auditory nerve with speech to gradually build a conditioned reflex, thereby achieving the goal of awakening the patient. This helps alleviate the suppression of the respiratory center by the cerebral cortex, effectively strengthening the patient's cough function, enabling the patient to actively clear nasal secretions, thus maintaining airway patency and reducing pneumonia caused by mechanical ventilation. S2: To improve the ability of medical staff to assess patients' conscious state by evaluating indicators such as BAEP during treatment, ensure accurate understanding of patients' physiological state, and adopt reasonable and effective mechanical ventilation programs to reduce patients' ventilation time and the occurrence of respiratory complications. Auditory stimulation may cause patients to experience maladaptive stimuli and agitation, such as adverse reactions like patient-ventilator asynchrony. S3: By regulating the balance of DLPFC in both cerebral hemispheres through anodic tDCS in the left DLPFC region and cathodic tDCS in the right DLPFC region, the patient's emotional disorders can be effectively improved, thus playing a role in regulating emotions and improving depressive state. Mirror neurons have been proven to play an important role in human imitation learning. Using advanced virtual reality technology, patients are first asked to observe certain daily limb movements and then actively imitate them, which enhances the patient's "immersion" in the treatment process. This approach helps to promote neural plasticity and accelerate the recovery of functional impairment. S4: Stimulation begins, the discharge switch is turned on, the energy storage capacitor discharges to the stimulation coil, the stimulation current rises, a time-varying induced magnetic field is generated around the stimulation coil, and an induced electric field is induced on the neuron, causing the neuronal membrane potential to rise. When the neuronal membrane potential reaches the initial discharge threshold Vth(1) = 10mV, the control module provides a turn-off signal to the discharge switch, and the first stimulation ends. Before the second stimulation begins: the initial discharge threshold Vth(1) = 10mV of the neuronal membrane potential is input into the neuronal dynamic threshold prediction model. The discharge threshold Vth increases at the moment of discharge and according to the neuronal dynamic threshold prediction model, (V th (1)+ΔV) is the maximum value, and it gradually decreases from the maximum value with the time constant τA; the voltage detection module extracts the voltage value across the energy storage capacitor and inputs it into the control module. The control module provides a conduction signal to the charging switch S. The charging ends when the voltage across the energy storage capacitor recovers to the preset value. S5: Propofol has a strong vasodilatory effect. When TCI is induced, it reaches the set plasma target concentration in a short time, which often leads to hypotension after general anesthesia induction, especially when combined with fentanyl-like drugs. The degree of propofol's effect on the circulatory system is closely related to the time, dosage, and injection rate. At time points such as 3 minutes after anesthesia intubation, 1 hour after cerebral cortex incision, and 1 hour after tumor resection, the patient's blood pressure decreased. The MAP decrease in the closed-loop group was less than that in the target-controlled group. After general anesthesia induction, the patient's BIS decreased rapidly. When the set feedback value (BIS=50) was reached, the feedback regulation of the closed-loop group was activated, and the propofol infusion volume was reduced. Therefore, the MAP change tended to be stable. There was no obvious hypertension reaction during strong stimulation operations such as intubation, skin incision, skull sawing, and skin suturing, indicating that the depth of anesthesia was sufficient for the operation. Throughout the anesthesia process, the closed-loop group could accurately control the depth of anesthesia, reduce intraoperative blood pressure fluctuations, and facilitate brain tissue perfusion.

2. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: The aforementioned electrical nerve stimulation may promote awakening by altering the levels of neurotransmitters in the body. The increase in dopamine levels before and after stimulation in comatose patients is related to the improvement in consciousness. Patients with low dopamine levels before stimulation showed a significant increase in dopamine levels after stimulation, and their probability of awakening was higher than that of patients with normal or higher-than-normal dopamine levels before treatment. In addition to routine comprehensive treatment, bilateral median nerve electrical stimulation was used to treat comatose patients after traumatic brain injury. The stimulation group experienced shorter coma time, faster recovery of consciousness, and better prognosis than the control group. Measurements of β-endorphin levels in cerebrospinal fluid before and after stimulation revealed a significant decrease in β-endorphin levels in the stimulation group compared to the control group. This suggests that the awakening effect of median nerve electrical stimulation on comatose patients after traumatic brain injury may be due to its inhibition of β-endorphin release in acute comatose patients, reversing its inhibitory and damaging effects on the central nervous system, effectively inhibiting intracranial pressure increases, reducing cerebral edema, and preventing the degeneration of neurons and glial cells.

3. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: The nursing staff will periodically stimulate the patient's hearing with sounds, such as clapping or whistling near the ear, for about 15 seconds each time, and record the patient's response and physiological parameters. For responsive patients, nurses can use methods such as repeated calling and repeated instructions to strengthen the patient's nerve reflexes. Under the guidance and supervision of the nurses, certain skin cleaning work should be done, such as washing the face and feet with hot water in the morning and evening, and applying lotion to the whole body. At the same time, the nurses should help the patient change positions at certain times and massage the patient's limbs, from the joints of the two upper limbs to the joints of the two lower limbs, for about 20 minutes. In order to prevent problems such as venous thrombosis caused by prolonged bed rest, the patient can take medication twice a day. At the same time, the nurses can use a soft brush on the patient's extremities every day, and instruct the patient's family members to touch the sensitive areas of the patient's head and earlobes multiple times. The nurses can conduct initial physical function training, passively moving the joints of the limbs five times a day, for about 20 minutes each time.

4. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: The behavioral sensory stimulation primarily enhances the activity of cerebral cortex cells by stimulating the skin, light, movement, and temperature sensations. It also improves blood circulation, accelerates awakening, and promotes faster recovery of consciousness. Systematic auditory stimulation utilizes sound waves generated by speech signals to stimulate the ascending brainstem, strengthening physiological activity and neural responses. This effectively stimulates the brain and consciousness, promoting recovery. The combination of behavioral sensory stimulation and systematic auditory stimulation has shown significant clinical efficacy in waking patients with severe traumatic brain injury and coma. It can improve their quality of life, aid in the self-recovery of neurological function, and enhance their state of consciousness, thereby accelerating awakening.

5. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: The study used elbow joint position sense error to assess patients' sensory function before and after treatment. Brain-computer interface combined with peripheral FES was more effective in improving upper limb elbow joint position sense in stroke patients than peripheral FES alone. Brain-computer interface-based motor rehabilitation may improve patients' sensory function. The efficacy of brain-computer interface combined with peripheral motor task therapy based on sensorimotor rhythm in stroke patients was also investigated. The results showed that, compared with simple motor trial training and peripheral tactile stimulation, the combined training method was more effective in improving upper limb sensory function in stroke patients.

6. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: If the slope of the stimulation current remains unchanged before and after the zero point, a stimulation current pulse cycle can be divided into three segments: one rising edge and two falling edges. If the slope of the stimulation current changes before and after the zero point, a stimulation current pulse cycle can be divided into four segments: two rising edges and two falling edges. When N=2, it can provide eight discharge voltage levels, four positive and four negative. It can not only realize the first type of biphasic approximate triangular wave stimulation current, but also generate the second type of biphasic approximate triangular wave stimulation current. There are two stimulation modes of biphasic stimulation current in TMS: intracranial anterior-posterior current stimulation mode and intracranial posterior-anterior current stimulation mode.

7. The closed-loop transcranial brain stimulation system and method according to claim 1, characterized in that: Glycerol is produced by glycolysis or degradation of glycerophosphate membranes by phosphokinases. An increase in glycerol content indicates lipid metabolism and brain cell membrane damage. In traumatic brain injury, an increase in glycerol content indicates brain cell membrane damage. Therefore, glucose, lactate, and glycerol can be specific indicators of traumatic brain injury. A comparison was made between BIS closed-loop targeted infusion of propofol and traditional propofol sedation. The results showed that BIS closed-loop targeted infusion had a better and more stable sedation effect.

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