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CN-122006104-A - Self-adaptive control method and system of percutaneous nerve stimulation equipment

CN122006104ACN 122006104 ACN122006104 ACN 122006104ACN-122006104-A

Abstract

The application relates to the technical field of medical instrument control, and discloses a self-adaptive control method and a self-adaptive control system for percutaneous nerve stimulation equipment. The method uses the ending time of the electric stimulation pulse as a time sequence datum point, and sets the starting time of a sampling time window as the delay time after the time sequence datum point During the duration and delay time of the electric stimulation pulse The method comprises the steps of collecting internal shielding signals, enabling an optical sensing module to collect photoelectric volume pulse wave signals only in a stable period after mechanical tremor of muscles subsides, carrying out interpolation fitting on waveforms in a shielded period by using effective signal segments in adjacent sampling time windows as interpolation nodes to reconstruct continuous venous blood flow waveforms, extracting venous filling time VRT from the reconstructed waveforms, and adjusting the stimulation interval time of the next period according to deviation values of the VRT and a current stimulation period T. The application avoids the interference of motion artifact and simultaneously realizes the automatic matching of the stimulation frequency and the vein filling circadian rhythm of the user.

Inventors

  • ZHANG MINGKUN
  • NIU BO

Assignees

  • 昆山雷盛医疗科技有限公司

Dates

Publication Date
20260512
Application Date
20260129

Claims (10)

  1. 1. A method for adaptively controlling a transcutaneous nerve stimulation device, comprising the steps of, performed by a controller: s1, controlling a stimulation output module to output electric stimulation pulses according to a current stimulation period T, and recording the pulse ending time as a time sequence datum point; S2, setting a sampling time window, wherein the starting moment of the sampling time window is the delay time after the time sequence datum point The delay time is For avoiding mechanical tremor caused by muscle contraction, activating an optical sensing module to acquire a photoplethysmography signal in the sampling time window, wherein the photoplethysmography signal is acquired during the electrical stimulation pulse duration and the delay time In, shielding signal acquisition or marking the time period data as invalid; S3, calculating a signal quality index Q for the photoelectric volume pulse wave signals acquired in the sampling time window, when the signal quality index Q is lower than a preset quality threshold value Maintaining the current stimulation period T to enter the next period when the signal quality index Q is not lower than the quality threshold Step S4 is carried out; S4, interpolation fitting is carried out on the signal waveforms which are shielded or marked as invalid periods in the step S2 by using the effective signal fragments acquired in the adjacent sampling time windows as interpolation nodes, and continuous venous blood flow waveforms are reconstructed; s5, calculating a period deviation value Wherein According to the periodic deviation value The stimulation interval time of the next period is adjusted.
  2. 2. The method according to claim 1, wherein in step S2, the delay time is The range of values of (2) is 50 milliseconds to 200 milliseconds.
  3. 3. The method according to claim 1, wherein in step S3, the signal quality index Q is calculated by at least one of the following: calculating the signal-to-noise ratio of the photoplethysmogram signals in the sampling time window, the quality threshold The corresponding signal to noise ratio threshold value; Calculating the baseline drift amplitude of the photoplethysmography signals in the sampling time window, wherein the quality threshold value The corresponding value is a drift threshold value; detecting whether the photoelectric volume pulse wave signal in the sampling time window has a saturation point or a cut-off point, wherein the quality threshold value The corresponding is the outlier threshold.
  4. 4. The method according to claim 1, characterized in that in step S4, the interpolation fit employs a piecewise linear interpolation algorithm or a spline interpolation algorithm.
  5. 5. The method according to claim 1, characterized in that in step S4, the specific step of extracting the venous filling time VRT comprises: S4a, performing smoothing filtering processing on the reconstructed venous blood flow waveform to remove high-frequency noise; step S4b, identifying trough points caused by muscle contraction extrusion in the reconstruction waveform The trough point Corresponding to the lowest venous blood volume moment; Step S4c, from the trough point Initially, the waveform is searched forward along the time axis to return to the steady point of steady state The judging condition of the stable state is that the duration time of the waveform slope continuously lower than the slope threshold reaches the preset stable judging duration time; Step S4d, calculating the wave trough point To the stable point As the venous filling time VRT.
  6. 6. The method according to claim 1, wherein in step S5, the method is based on the periodic deviation value The adjusting the stimulation interval time of the next period specifically comprises: when the period deviation value is When the stimulation frequency is positive and exceeds a first threshold value, judging that the current stimulation frequency is too fast, and prolonging the stimulation interval time of the next period; when the period deviation value is When the current stimulation frequency is a negative value and the absolute value of the current stimulation frequency exceeds a second threshold value, judging that the current stimulation frequency is too slow, and shortening the stimulation interval time of the next period; when the period deviation value is When the absolute value of (c) does not exceed the corresponding threshold, maintaining the current stimulation period T unchanged.
  7. 7. The method according to claim 6, wherein in step S5, the adjustment of the stimulus interval time of the next cycle employs a gradual adjustment strategy, wherein the change in stimulus interval time of a single adjustment does not exceed a preset maximum adjustment step size The maximum adjustment step length The value of (2) is in the range of five to twenty percent of the current stimulation period T.
  8. 8. The method of claim 6, further comprising the step of phase-triggered optimization: when the period deviation value is After the absolute value of the controller is not more than the corresponding threshold value and the stimulation period is basically matched with the venous filling time, the absolute value of the controller enters a phase optimization mode; in the phase optimization mode, the controller identifies venous filling phases based on the photo-volume pulse wave signals acquired in real time; When the current venous blood volume is detected to be close to the filling peak value, the next electric stimulation pulse output is triggered, so that the stimulation time is synchronous with the venous filling peak value in phase.
  9. 9. The method of claim 8, wherein the method of identifying venous filling phase comprises: monitoring the real-time change trend of the photoelectric volume pulse wave signal; When the signal amplitude changes from an ascending trend to a stable or starts to descend, judging that the current moment is close to a filling peak value; The stimulus output is triggered within a preset response time after the decision to approach the filling peak.
  10. 10. An adaptive control system for a transcutaneous nerve stimulation device, comprising: a stimulus output module configured to generate an electrical stimulus pulse signal of adjustable period and pulse width; the optical sensing module is configured to collect photoelectric volume pulse wave signals of the target part; The main control module is respectively connected with the stimulation output module and the optical sensing module; The main control module comprises a time sequence control unit, a signal processing unit and a parameter adjusting unit; The time sequence control unit is configured to control the stimulation output module to output the electric stimulation pulse according to the current stimulation period T, record the pulse end time as a time sequence reference point and control the delay time of the optical sensing module only after the time sequence reference point Then, a sampling time window is opened to collect effective data, and the duration of the electric stimulation pulse and the delay time are carried out Internal shielding signal acquisition or marking the time period data as invalid, wherein the delay time For avoiding the mechanical tremor phase induced by muscle contraction; The signal processing unit is configured to calculate a signal quality index Q for the photoelectric volume pulse wave signals acquired in the sampling time window when the signal quality index Q is not lower than a quality threshold When the method is used, interpolation fitting is carried out by using the effective signal segments collected in the adjacent sampling time windows as interpolation nodes, continuous venous blood flow waveforms are reconstructed, and venous filling time VRT is extracted from the reconstructed waveforms; the parameter adjusting unit is configured to calculate a period deviation value of the venous filling time VRT and the current stimulation period T According to the periodic deviation value And generating a stimulation parameter adjusting instruction according to the size and the direction of the stimulation parameter, and sending the stimulation parameter adjusting instruction to the stimulation output module so as to adjust the stimulation interval time of the next period.

Description

Self-adaptive control method and system of percutaneous nerve stimulation equipment Technical Field The application relates to the technical field of medical appliances, in particular to a self-adaptive control technology of percutaneous nerve stimulation equipment. Background The percutaneous nerve electrical stimulation technology induces rhythmic contraction of corresponding muscles by applying electrical stimulation pulses to target nerves, and promotes venous blood backflow by utilizing muscle pumping action, so that the percutaneous nerve electrical stimulation technology has wide application value in the clinical and rehabilitation fields. In the application scenario of deep vein thrombosis prevention of lower limbs, the percutaneous nerve electrical stimulation equipment is usually attached to the total sural nerve running area, and the deep vein of the lower limbs is extruded by stimulating and inducing the contraction of gastrocnemius muscles, so that the venous blood is promoted to flow back to the heart direction, and the thrombosis risk caused by long-time bedridden or sedentary is reduced. In the application scene of postoperative rehabilitation, patients have limited postoperative activities, the venous return capacity of lower limbs is reduced, and the muscle pump function during normal walking needs to be simulated by means of percutaneous nerve electrical stimulation to maintain the blood circulation of lower limbs. In the application scenario of long-distance travel protection, passengers can easily pool venous blood of lower limbs due to long-time sitting, and the portable percutaneous nerve stimulation device can be used for promoting blood circulation of lower limbs in travel. In the above application scenario, in order to achieve effective venous blood drainage, the intensity of the electrical stimulation needs to reach a threshold level sufficient to induce visible muscle contraction. However, the muscle contraction process is necessarily accompanied by mechanical tremors, which can cause a drastic change in the contact state between the optical sensor attached to the skin surface and the skin, thereby introducing serious motion artifacts in the photoplethysmographic signals. The prior art generally adopts a signal filtering algorithm to try to separate effective blood flow signal components from polluted acquired data, but as the amplitude of motion artifact is far more than that of effective blood flow signals and the two are overlapped in frequency spectrum, the filtering effect is unsatisfactory, so that the acquired data during the stimulation cannot be used for closed loop feedback control. In addition, most of the existing percutaneous nerve stimulation devices employ a stimulation output mode of a fixed frequency. However, there are significant differences in venous return capacity from individual to individual, and the venous filling time of the same individual in different physiological states may also vary. When the stimulation frequency is too fast, the vein is squeezed again before filling, an empty pumping effect is formed, and the pumping efficiency is reduced, and when the stimulation frequency is too slow, the vein is filled but the stimulation is delayed, so that efficiency loss exists, and the risk of blood stasis is possibly increased. The stimulation scheme with fixed frequency cannot be adaptively adjusted according to the current physiological state of a user, and optimal blood pumping effect is difficult to achieve under different individuals and different use situations. Therefore, a new technical scheme is urgently needed, which can reliably acquire blood flow monitoring data under the interference environment of muscle contraction caused by strong electric stimulation, and realize automatic matching of the stimulation frequency and the vein filling circadian rhythm of a user based on the data. Disclosure of Invention The present application is directed to a method and a system for adaptively controlling a transcutaneous nerve stimulation device, so as to solve the problems set forth in the background art. The application discloses a self-adaptive control method of a percutaneous nerve stimulation device, which comprises the following steps executed by a controller: s1, controlling a stimulation output module to output electric stimulation pulses according to a current stimulation period T, and recording the pulse ending time as a time sequence datum point; S2, setting a sampling time window, wherein the starting moment of the sampling time window is the delay time after the time sequence datum point The delay time isFor avoiding mechanical tremor caused by muscle contraction, activating an optical sensing module to acquire a photoplethysmography signal in the sampling time window, wherein the photoplethysmography signal is acquired during the electrical stimulation pulse duration and the delay timeIn, shielding signal acquisition or marking the time period