A peritoneal dialysis solution constant temperature supply and flow self-adaptive regulation system

Abstract

The present application relates to the technical field of automatic peritoneal dialysis machine, and particularly relates to a peritoneal dialysis fluid constant-temperature supply and flow self-adaptive regulation and control system; comprising: a liquid supply driving module, a non-contact end heating module, a multi-dimensional signal sensing module and a temperature-pressure coupling multi-state collaborative control module; the present application introduces a non-contact electromagnetic resonance end heating structure and a temperature-pressure coupling multi-state collaborative control algorithm, on the one hand, uses air gap and high-frequency electromagnetic eddy current to realize safe endogenous heat of dialysis fluid in the pipeline, effectively avoids the risk of local thermal deformation and plasticizer precipitation of the pipeline caused by traditional contact heating, improves the biological safety of fluid infusion, constructs a feedforward defense mechanism based on the change rate of end temperature, and through extraction of the dynamic amplitude and static component of the hydraulic waveform, realizes accurate identification of cold stimulation spasm, regular physiological disturbance and pipeline mechanical obstruction, and after diagnosing mechanical obstruction, actively drives the stepping motor to perform reverse backflushing action.

Description

Technical Field

[0001] This invention relates to the field of automated peritoneal dialysis machine technology, specifically to a peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system. Background Technology

[0002] Automated peritoneal dialysis machines use a fluid-driven device to regularly infuse dialysate into the patient's peritoneal cavity, relying on the semi-permeable membrane properties of the peritoneum for solute exchange. In practical clinical applications, existing technologies mainly suffer from the following three core technical deficiencies:

[0003] 1. Regarding dialysate temperature control, existing heating systems are mostly located at the main unit. Before the dialysate flows through a long external tubing into the body, significant heat loss occurs. To compensate for this end-point heat loss, some solutions use resistance heating wires attached to the outside of the tubing for secondary compensation. However, due to the poor thermal conductivity of medical-grade polyvinyl chloride (PVC) tubing, contact heat conduction easily leads to localized heat accumulation on the outer wall of the tubing. This not only easily causes thermoplastic softening and deformation of the tubing material but may also promote the release of harmful plasticizers from inside the tubing into the dialysate, posing a high risk of biocompatibility issues.

[0004] 2. Regarding perfusion pressure monitoring and fluid control, existing dialysis systems generally employ single-dimensional threshold monitoring logic where temperature and pressure are independent. When insufficiently heated, cold dialysate enters the peritoneal cavity, the low-temperature stimulation triggers peritoneal vasoconstriction and local abdominal muscle spasms. This physiological spasm forces a passive increase in intra-abdominal pressure, causing sensors to detect abnormally high pressure peaks. Because existing systems lack a coupling and decoupling mechanism between temperature drops and pressure surges, they are highly susceptible to misinterpreting this spasm as a fluid pathway obstruction, thus triggering invalid shutdown alarms.

[0005] 3. Existing pressure sensing systems lack the ability to analyze the frequency domain and amplitude of fluid dynamic waveforms. During dialysis perfusion, normal physiological breathing, changes in body position, or coughing can all cause instantaneous fluctuations in hydraulic pressure within the tubing. Existing equipment cannot accurately distinguish between these physiological disturbances and mechanical obstructions such as tubing kinks or fibrin coagulation. Furthermore, existing equipment can only passively shut down and cut off power upon detecting high pressure, lacking an active physical mechanism to clear mechanical obstructions. This results in a high false alarm rate, heavily relying on frequent manual intervention by medical staff, and reducing the continuity and adherence of home dialysis treatment. Summary of the Invention

[0006] To achieve the above objectives, the present invention provides a peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system, comprising: a fluid supply drive module, including a peristaltic pump and dialysis tubing, for providing perfusion power for the input of dialysis fluid into the patient's peritoneal cavity;

[0007] A non-contact end heating module is fitted onto the end of the dialysis tubing near the patient. The non-contact end heating module has a resonant cavity inside, and the dialysis tubing passes through the resonant cavity with a gap between it and the inner wall of the cavity. This module is used to perform non-contact electromagnetic eddy current micro-heating on the dialysis fluid in the tubing.

[0008] A multi-dimensional signal sensing module is located downstream of the non-contact end heating module. It includes a high-frequency temperature sensor and a micro-pressure sensor, which are used to collect the end temperature signal of the patient's pre-peritoneal dialysis fluid and the hydraulic waveform signal in the pipeline in real time, respectively.

[0009] The temperature-pressure coupling multi-state collaborative control module is communicatively connected to the liquid supply drive module, the non-contact end heating module, and the multi-dimensional signal sensing module, respectively; the collaborative control module is configured to perform the following operations:

[0010] The temperature change rate is calculated based on the real-time collected end temperature signal. When the temperature change rate meets the preset cold stimulus negative drop condition, the output power of the non-contact end heating module is increased simultaneously and the infusion flow rate of the peristaltic pump is actively reduced to carry out cold stimulus spasm feedforward defense.

[0011] The three-dimensional feature state is extracted from the real-time collected hydraulic waveform signal. Based on the frequency and amplitude fluctuation characteristics of the waveform, the pipeline state is identified as physiological breathing confirmation state, body position change disturbance resistance state, or real physical blockage state. The peristaltic pump is then linked to perform mechanical actions to maintain the original speed, suspend the instantaneous flow, or reverse to clear the blockage.

[0012] Furthermore, the liquid supply drive module includes:

[0013] A bidirectional high-precision stepper motor and the pump head assembly connected to it;

[0014] The control terminal of the stepper motor is electrically connected to the temperature-pressure coupling multi-state collaborative control module, and is used to receive and respond to the instantaneous flow suspension command to achieve millisecond-level braking and stopping, and to respond to the reverse unblocking command to output reverse rotation torque, thereby driving the pump head assembly to perform negative pressure back suction of the liquid in the dialysis pipeline.

[0015] Furthermore, the non-contact end heating module specifically includes:

[0016] The outer shell has a hollow interior forming the resonant cavity;

[0017] A high-frequency electromagnetic induction coil is embedded in the inner wall of the outer casing;

[0018] A tubing limiting bracket is provided at both ends of the resonant cavity to suspend and fix the dialysis tubing on the central axis of the resonant cavity.

[0019] In this system, an annular air gap with a constant radial width is formed between the outer wall of the fixed dialysis tubing and the high-frequency electromagnetic induction coil. The temperature-pressure coupling multi-state collaborative control module adjusts the frequency of the alternating current supplied to the high-frequency electromagnetic induction coil, so that the alternating magnetic field passing through the annular air gap directly excites eddy currents in the dialysate inside the dialysis tubing to generate heat.

[0020] Furthermore, the non-contact end heating module includes:

[0021] A heat-insulating shielding layer is disposed on the outer surface of the outer shell to prevent electromagnetic radiation leakage and burns to patients due to excessively high outer surface temperature.

[0022] Furthermore, the non-contact end heating module also includes;

[0023] The non-contact end heating module is spatially located at the point where the dialysis tubing is connected to the patient's abdominal catheter. At the end of the pipeline.

[0024] Furthermore, a medical-grade flexible fluid isolation membrane is provided between the micro-pressure sensor in the multi-dimensional signal sensing module and the dialysis tubing;

[0025] The multidimensional signal sensing module also includes a front-end signal conditioning circuit connected to the high-frequency temperature sensor and the micro-pressure sensor. The front-end signal conditioning circuit is configured to perform hardware-level low-pass filtering and amplification on the acquired raw analog signal, and output a discrete-time end-temperature sequence signal after analog-to-digital conversion. With hydraulic waveform sequence signal ,in These are discrete-time sampling points.

[0026] Furthermore, the determination step for the cold stimulation negative drop condition includes:

[0027] The temperature-pressure coupled multi-state collaborative control module receives the terminal temperature sequence signal. The exponential moving average algorithm is used for smoothing and denoising to obtain smoothed temperature values. The calculation formula is as follows:

[0028]

[0029] in, The preset smoothing coefficient, and ;

[0030] Subsequently, within the preset sliding time window Calculate the real-time dynamic temperature change rate of the dialysate. The calculation formula is as follows:

[0031]

[0032] in, The number of sampling points within the sliding time window. The sampling period; when multiple consecutive sampling points When the threshold is less than the preset negative cold stimulation threshold, the cold stimulation spasm feedforward defense is triggered.

[0033] Furthermore, the specific calculation model for extracting the three-dimensional feature states of the real-time acquired hydraulic waveform signal is as follows:

[0034] The temperature-pressure coupled multi-state collaborative control module converts discrete-time hydraulic waveform sequence signals. Decoupling to static intra-abdominal pressure components and dynamic alternating components ;

[0035] The static intra-abdominal pressure component By setting the length to The moving average filter extraction is calculated using the following formula:

[0036]

[0037] The dynamic alternating component ;

[0038] The collaborative control module controls the dynamic alternating components. Peak-to-peak value extraction is performed within a preset observation window, and dynamic amplitude characteristic values ​​are calculated. :

[0039]

[0040] in, Belongs to the current observation window;

[0041] when When the waveform is in the first extreme value range and the zero-crossing rate matches the physiological breathing frequency range, it is determined to be in the physiological breathing confirmed state.

[0042] when The first difference value is out of bounds and When it is in the second extreme value range, it is determined to be a positional mutation-resistant state;

[0043] When the static intra-abdominal pressure component It exhibits a non-periodic, continuous monotonically increasing trend, and during this period When the value approaches zero, it is determined to be a true physical blockage state.

[0044] Furthermore, after triggering the cold stimulation spasm feedforward defense, the temperature-pressure coupled multi-state collaborative control module executes flow smoothing ramp-up logic based on temperature recovery:

[0045] During the deceleration infusion, the collaborative control module continuously monitors the real-time dynamic temperature change rate. With the smoothed temperature value ;

[0046] When satisfied And multiple consecutive sampling periods When all temperatures fall within the preset safe body temperature range, it is determined that the disturbance to the cold end environment of the pipeline has been eliminated and the risk of cold stimulation spasm has been relieved.

[0047] At this point, the collaborative control module does not immediately restore the initial flow rate, but instead uses a smoothing curve algorithm to control the peristaltic pump's infusion flow rate within a preset buffer time window. The flow rate is gradually increased from a low level to a step-by-step or continuous increase until it returns to the initially set target perfusion flow rate.

[0048] Furthermore, when the temperature-pressure coupled multi-state collaborative control module determines that the pipeline state is the actual physical blockage state, it executes anti-false alarm self-healing and safety circuit breaker logic based on retry counting. The specific steps are as follows:

[0049] S1: Control the peristaltic pump to reverse the rotation a preset number of times to perform a retraction action, and record the number of retraction retries in the system register. Perform an increment operation;

[0050] S2: After the aspiration action is completed, control the peristaltic pump to rotate forward and tentatively resume perfusion at a low speed, and extract the dynamic amplitude characteristic value within the current observation window again. With static intra-abdominal pressure component ;

[0051] S3: If the waveform characteristics extracted a second time match the physiological respiration confirmation state, then the tubing blockage is determined to have been successfully cleared, and the retry count is reset to zero. And restore the target perfusion flow rate;

[0052] S4: If the waveform features extracted a second time are still determined to be a real physical blockage state, then repeat steps S1 to S3; when the number of retries... Reaching the preset maximum retry threshold When the peristaltic pump is powered off and braked, the high-frequency alternating current of the non-contact end heating module is simultaneously cut off, and the audible and visual alarm module is activated to issue a manual intervention alarm.

[0053] Beneficial effects

[0054] This invention introduces a non-contact electromagnetic resonant end heating structure and a temperature-pressure coupled multi-state collaborative control algorithm.

[0055] On the one hand, by utilizing air gaps and high-frequency electromagnetic eddy currents, safe internal heat generation of the dialysate is achieved inside the pipeline, effectively avoiding the risks of local thermal deformation of the pipeline and plasticizer precipitation caused by traditional contact heating, thus improving the biosafety of fluid infusion.

[0056] On the other hand, a feedforward defense mechanism based on the rate of change of terminal temperature was constructed. By extracting the dynamic amplitude and static components of the hydraulic waveform, accurate identification of cold-induced spasms, routine physiological disturbances, and mechanical obstruction of the tubing was achieved. Upon diagnosis of mechanical obstruction, a stepper motor was actively driven to perform a reverse suction and unblocking action. This technical solution changes the traditional single-variable passive alarm mode, effectively reducing the false alarm rate of the system and improving the continuity and anti-interference capability of the automated peritoneal dialysis process. Attached Figure Description

[0057] Figure 1 This is a flowchart of the collaborative control logic of the present invention;

[0058] Figure 2 This is a system architecture diagram of the present invention. Detailed Implementation

[0059] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0060] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0061] The present invention will now be described in further detail with reference to the accompanying drawings:

[0062] Example:

[0063] like Figures 1-2 As shown, the present invention provides a peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system, comprising:

[0064] The fluid supply drive module, including a peristaltic pump and dialysis tubing, is used to provide perfusion power for the infusion of dialysis fluid into the patient's peritoneal cavity;

[0065] A non-contact end heating module is fitted onto the end of the dialysis tubing near the patient. The non-contact end heating module has a resonant cavity inside, and the dialysis tubing passes through the resonant cavity with a gap between it and the inner wall of the cavity. This module is used to perform non-contact electromagnetic eddy current micro-heating on the dialysis fluid in the tubing.

[0066] A multi-dimensional signal sensing module is located downstream of the non-contact end heating module. It includes a high-frequency temperature sensor and a micro-pressure sensor, which are used to collect the end temperature signal of the patient's pre-peritoneal dialysis fluid and the hydraulic waveform signal in the pipeline in real time, respectively.

[0067] The temperature-pressure coupling multi-state collaborative control module is communicatively connected to the liquid supply drive module, the non-contact end heating module, and the multi-dimensional signal sensing module, respectively; the collaborative control module is configured to perform the following operations:

[0068] The temperature change rate is calculated based on the real-time collected end temperature signal. When the temperature change rate meets the preset cold stimulus negative drop condition, the output power of the non-contact end heating module is increased simultaneously and the infusion flow rate of the peristaltic pump is actively reduced to carry out cold stimulus spasm feedforward defense.

[0069] The three-dimensional feature state is extracted from the real-time collected hydraulic waveform signal. Based on the frequency and amplitude fluctuation characteristics of the waveform, the pipeline state is identified as physiological breathing confirmation state, body position change disturbance resistance state or real physical blockage state, and the peristaltic pump is controlled to perform mechanical actions such as maintaining the original speed, suspending the instantaneous flow or reversing to clear the blockage.

[0070] Furthermore, the specific operation procedure of the liquid supply drive module is as follows:

[0071] In this embodiment, the fluid supply drive module serves as the fluid delivery and dynamic adjustment execution terminal of the entire peritoneal dialysis control system. Its core function is not only to provide basic perfusion power, but also to respond precisely and without delay to complex physical action commands output by the front-end algorithm.

[0072] Specifically, the pump head assembly contains a rotor assembly with multiple evenly distributed compression rollers. The dialysis tubing is fitted between the inner wall of the pump head assembly and the rotor assembly at a specific wrap angle. Driven by a stepper motor, the rotor assembly drives the compression rollers to periodically roll, compress, and release along the outer wall of the dialysis tubing. Relying on the tubing's own elastic restoring force and the physical pushing of the rollers, a continuously progressive sealed volume cavity is formed inside the tubing, thereby achieving directional pumping of the dialysate. This structure achieves complete physical isolation between the mechanical transmission components and the sterile dialysate.

[0073] To meet the system's need for rapid intervention in abnormal states, the drive circuit of the bidirectional high-precision stepper motor is deeply customized to cooperate with the special commands issued by the temperature-pressure coupled multi-state collaborative control module. Conventional unidirectional infusion pumps, after power is cut off, experience uncontrollable residual rotation of the rotor due to fluid inertia and mechanical inertia, causing additional fluid to be pushed into the abdominal cavity. To overcome this deficiency, the stepper motor drive system in this embodiment introduces active phase current control technology. When receiving the "instantaneous flow suspension" command from the collaborative control module, the drive circuit changes the energizing logic of the stepper motor stator windings within microseconds, injecting DC excitation current into a specific winding, thereby generating a large static holding torque between the stator and rotor. This holding torque forces the rotor to achieve hard braking and stop within an extremely short time window (milliseconds), completely eliminating the overshoot caused by fluid inertia and ensuring that the hydrostatic pressure applied to the patient's abdominal cavity no longer increases due to mechanical lag.

[0074] On the other hand, this module possesses a self-healing ability to reverse aspirate in case of physical blockages in the tubing (such as fibrin coagulation or catheter kinking). Upon receiving a "reverse unblocking" command, the stepper motor drive circuit alters the pulse commutation sequence of the multiphase windings, causing the stepper motor to output a reverse rotational torque. In this operating state, the compression rollers within the pump head assembly roll in reverse, reversing the original fluid propulsion direction and instantly creating a negative pressure environment within the dialysis tubing, especially in the distal region near the patient's peritoneal catheter interface. This negative pressure backflow effect, based on the reverse operation of the volumetric pump, effectively applies a reverse drag force to the blockage, thereby performing an active physical unblocking action.

[0075] Furthermore, the specific operating procedure for the non-contact terminal heating module is as follows:

[0076] The specific implementation architecture and thermodynamic control mechanism of the non-contact end heating module:

[0077] In actual clinical applications of peritoneal dialysis, dialysate is prone to severe heat loss during the final stage of its flow through long tubing into the peritoneal cavity. To completely resolve this "cold end effect" and avoid the risks of tubing melting and plasticizer leaching associated with traditional resistance wire bonding heating, this embodiment systematically constructs a non-contact end heating module approximately 10 to 20 centimeters from the end of the dialysis tubing at the patient's peritoneal catheter connection interface. This specific spatial range not only compresses the length of the unheated cold end tubing to its physical limit but also ensures a sufficient safe buffer distance between the heating device and the patient's body, avoiding mechanical interference or compression.

[0078] Delving into the internal physical topology of this module, its main body is composed of multiple layers of coaxial nested cylindrical structural components. The outermost layer is a composite material thermal insulation shielding layer. This layer not only has an extremely low thermal conductivity to prevent burns to patients from rising surface temperatures, but also contains a high-density metal shielding mesh embedded within it. This mesh is used to strictly confine the high-frequency electromagnetic radiation generated in the core heating area within the shell, preventing it from leaking out and causing electromagnetic interference (EMI) to surrounding life monitoring instruments (such as electrocardiogram monitors). Inside the outer shell, which is encased in the thermal insulation shielding layer, a cylindrical hollow resonant cavity extending through both ends is precisely milled.

[0079] As the core energy conversion device, the high-frequency electromagnetic induction coil is not exposed, but is completely embedded and fixed in the inner wall matrix of the hollow resonant cavity using injection molding or potting processes. To achieve truly "non-contact" heat transfer, polymer tubing limiting supports are fixed at the axial ports on both sides of the resonant cavity. When a medical-grade PVC dialysis tubing passes through this module, the tubing limiting supports use an elastic, adaptive clamping force to firmly suspend and constrain the dialysis tubing on the central geometric axis of the resonant cavity. This extremely stringent coaxiality positioning design ensures that a precisely formed annular air gap with a constant radial width is created between the outer wall of the dialysis tubing and the inner wall of the resonant cavity where the induction coil is embedded, throughout the entire length of the tubing.

[0080] Under this working mechanism, the system abandons the traditional "outside-in" heat conduction mode and instead adopts an "endogenous heat" mechanism through energy field penetration. When the temperature-pressure coupled multi-state collaborative control module supplies a high-frequency alternating current of a specific frequency to the high-frequency electromagnetic induction coil according to the real-time thermodynamic feedforward compensation algorithm, a high-density alternating magnetic field is immediately generated around the coil. This alternating magnetic field penetrates the annular air gap and the non-magnetic medical PVC tube wall without attenuation, directly acting on the dialysate flowing inside the tube. Because the dialysate is rich in sodium ions, chloride ions, and other conductive electrolyte components, the alternating magnetic field directly induces a closed eddy current electric field inside the fluid. Under the action of the eddy current, the flowing electrolyte liquid overcomes its own resistivity and spontaneously generates Joule heat, thereby achieving an instantaneous burst and uniform distribution of thermal energy.

[0081] Through the synergistic design of precision mechanical limiting and electromagnetic field coupling, the non-contact end-heating module generates heat directly within the dialysate. The PVC tubing itself no longer serves as a heat transfer medium, and its temperature remains consistently lower than or equal to the temperature of the internal fluid. This not only fundamentally eliminates the medical safety hazards of tubing softening and deformation or releasing toxic substances due to localized overheating, but also endows the heating system with extremely low thermal inertia. When the control module issues a command to adjust the heating power, the dialysate temperature can achieve a hysteresis-free response within milliseconds.

[0082] Furthermore, the specific operation procedure of the multi-dimensional signal sensing module is as follows:

[0083] In terms of hardware isolation and anti-aliasing pretreatment, considering the high salinity of peritoneal dialysis fluid and strict aseptic requirements, the system abandons the conventional design of directly immersing the sensor probe into the fluid tubing. A medical-grade flexible fluid isolation diaphragm with extremely low acoustic impedance is placed between the micro-pressure sensor and the fluid inside the dialysis tubing. This diaphragm can transmit the complex hydrostatic pressure inside the tubing and the weak alternating mechanical waves conducted from the peritoneal cavity to the piezoresistive sensitive element of the micro-pressure sensor without damage and linearly, while completely blocking cross-contamination between fluid particles and the biological barrier. The matching high-frequency temperature sensor uses an ultra-fine thin-film thermistor attached to a high thermal conductivity window on the outer wall of the tubing. The original weak analog signals captured by both are then fed into a highly integrated front-end signal conditioning circuit. After hardware-level low-pass filtering and differential amplification to suppress stray electromagnetic interference, the conditioning circuit converts the physical quantity in the continuous time domain into a discrete time domain sequence signal, namely the terminal temperature sequence signal, through a high-frequency analog-to-digital converter (ADC). With hydraulic waveform sequence signal ,in This represents the current discrete-time sampling point.

[0084] Upon entering the digital signal processing domain, simple absolute temperature threshold determination cannot meet the real-time requirements of anti-spasm control due to significant thermal hysteresis. Therefore, the system introduces a predictive algorithm model for discrete temperature sequences. The temperature-pressure coupled multi-state collaborative control module first processes the input terminal temperature sequence signal... An exponential moving average algorithm in the form of a first-order infinite impulse response is applied to filter out high-frequency thermal noise caused by fluid pulsation and obtain a smooth temperature value with a high signal-to-noise ratio. Its core iterative equation is expressed as:

[0085]

[0086] In the formula, The smoothing coefficient is calibrated based on the system's thermal inertia constant and strictly satisfies... Based on this smoothing benchmark, the system operates within a preset sliding time window. Inside, the first-order forward difference of the real-time dynamic temperature of the dialysate, i.e., the rate of change of dynamic temperature, is further solved. The transient drop acceleration used to characterize fluid temperature:

[0087]

[0088] In the formula, This represents the total number of discrete sampling points contained within the sliding time window. The fixed sampling period set for the system.

[0089] When the algorithm detects operators in multiple consecutive cycles When a significant negative value is displayed and the preset negative cold stimulation threshold boundary is breached, the system can rapidly feedforward to trigger a cold stimulation spasm defense action before the dialysate actually cools down to a temperature that would harm the patient's body temperature.

[0090] Parallel to thermodynamic calculations, for hydraulic waveform sequence signals The processing of this signal is the core of this system's solution to overcome the pain point of "false alarms". (Original signal) In reality, it is a deep superposition of pump source pulsating pressure, pipeline flow resistance pressure, the patient's actual intra-abdominal pressure, and physiological respiratory waves.

[0091] To implement precise mechanical linkage control, the control module constructed a signal decoupling mathematical model in the time domain. First, a set observation length of... A sliding mean filter is used to perform low-pass extraction on the original pressure sequence in the extremely low frequency band, thereby extracting the static intra-abdominal pressure component that characterizes the absolute degree of abdominal filling. Its mathematical expression is:

[0092]

[0093] Subsequently, a time-domain subtraction operation was performed. The system successfully filtered out slowly changing baseline pressure and extracted the dynamic alternating component, which contains extremely high physiological value. Based on this, the control module calculates the peak-to-peak value of the dynamic waveform, i.e., the dynamic amplitude characteristic value, within a scrolling feature observation window. :

[0094]

[0095] Based on the above rigorous mathematical decoupling parameters, the system ultimately performs the mapping and determination of three-dimensional characteristic states: when When the waveform is in a weak extreme range (e.g., a slight pressure difference corresponding to the movement of the human diaphragm), and the zero-crossing rate maps to the normal physiological breathing frequency range, the system is confirmed to be in a physiological breathing confirmed state, indicating that the fluid continuity is intact and there is no physical obstruction; when The first-order difference value undergoes an out-of-bounds step jump, and When the system instantly expands to the second extreme value range, it maps to a postural mutation-resistant state caused by the patient coughing or turning over; most importantly, when the static intra-abdominal pressure component is monitored... It exhibits a non-periodic, continuous, monotonically increasing trend, and the previously present weak physiological waveform completely disappears (i.e., When the value approaches zero, based on the fracture characteristics of the continuity equation in fluid mechanics, the system can definitively determine that air blockage, folding, or fibrin coagulation has occurred at the end of the peritoneal duct, thus accurately mapping it to a real physical blockage state, and triggering subsequent physical unblocking actions.

[0096] Furthermore, the specific operation procedure of the temperature-pressure coupled multi-state collaborative control module is as follows:

[0097] When dealing with cold stimulation conditions caused by ambient temperature disturbances, the system should adjust according to the dynamic temperature change rate. Upon triggering the cold-stimulation spasm feedforward defense, simultaneously increasing the non-contact heating power and decreasing the peristaltic pump speed, the module immediately initiates a smooth closed-loop servo logic based on thermodynamic state recovery. During low-speed safe infusion, the control module's background daemon continuously monitors the data fed by the multi-dimensional sensing module at a high-frequency clock. With smooth temperature value When the physical field calculation results satisfy (That is, the temperature of the dialysate in the tubing no longer shows an accelerated downward trend), and for multiple consecutive sampling cycles... When all temperatures are stably converged within the preset safe body temperature range of 37±0.2℃, the system determines that the heat dissipation disturbance in the cold end environment of the pipeline has been completely offset by the excessive Joule heat generated by the electromagnetic eddy current, and the risk of cold stimulation spasm is completely eliminated from the fluid boundary layer.

[0098] At this critical recovery point, to avoid a sudden change in flow rate causing a secondary mechanical hydraulic shock to the relaxed peritoneum of the patient, the control module never executes a step command that directly jumps to the target rotational speed. Instead, the system activates a built-in smooth approximation algorithm (such as cubic spline interpolation or an S-shaped acceleration / deceleration curve generator) within a preset buffer time window. Within a range of 30 to 60 seconds (e.g., the frequency of the peristaltic pump's underlying drive pulses is progressively increased non-linearly along a smooth curve from the current low-frequency state). This stepless, flexible acceleration mechanism ensures a perfect match between the dialysate flow rate and peritoneal compliance until the flow rate is imperceptible and smoothly returns to the initially set target perfusion standard.

[0099] Addressing the most challenging clinical issues of physical catheter blockage (such as fibrin coagulation and severe catheter kinking), this module incorporates a state machine with memory accumulation capabilities for false alarm prevention, self-healing, and safety circuit breaker. Once the front-end digital decoupling model is based on the static intra-abdominal pressure components... Non-periodic monotonically increasing and dynamic amplitude eigenvalues When the disappearance of the signal confirms that the current state is a "real physical blockage", the control module immediately cuts off the regular constant current injection timeline and enters the self-healing retry timeline.

[0100] Within the self-healing retry timeline, the system first issues a precise, quantitative reverse command to the liquid supply drive module, controlling the stepper motor to brake rapidly and rotate in the opposite direction a specified number of times. This utilizes the reverse deformation of the volumetric pump chamber to establish a transient negative pressure in the terminal pipeline for backflow and unblocking. Simultaneously, the number of backflow retry attempts is recorded in the system's non-volatile register. The process involves incrementing by 1 step. After a single pullback operation is completed, the control module does not immediately determine that the blockage has been successfully cleared. Instead, it enters a status verification subroutine: controlling the stepper motor to switch back to forward rotation, injecting a small amount of fluid into the pipeline at an extremely low, tentative flow rate, and then extracting real-time data a second time within a specific overlapping observation window. and Parameters.

[0101] If the waveform characteristics obtained from the secondary analysis reappear as alternating pressure differences consistent with the rhythm of human diaphragm movement, i.e., it is remapped back to the "physiological respiration confirmation state," the control module determines that the temporary physical obstruction has been successfully flushed away and removed by the reverse jet. At this point, the system automatically resets the retry count variable to zero. The system restores normal perfusion through the aforementioned smooth approximation algorithm. The entire process requires no physical intervention from medical staff or patients, achieving true system-level "silent self-healing".

[0102] If the waveform characteristics extracted a second time remain stuck in the "real physical blockage state," it indicates that a stubborn, dense blockage has been encountered that is difficult to resolve through fluid backflushing. At this point, the state machine enters a cyclic retry phase, repeatedly executing the pullback and probing actions. The retry count in the register... The system has reached its factory-preset maximum absolute retry threshold. (For example, if it fails three times in a row), the system determines that its mechanical error correction capability has reached its physical limit. To ensure the absolute safety of the patient's life, the control module will instantly throw the highest priority unmasked hardware interrupt (NMI): directly shutting off the power supply path of the stepper motor at the physical level to implement dead-zone braking, simultaneously cutting off the high-frequency excitation source of the non-contact end heating module to eliminate the risk of dry burning, and finally activating the audible and visual alarm circuit to send audible and visual beacons and remote telemetry radio frequency signals for manual intervention resuscitation to the outside world.

[0103] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system, characterized in that, include: The fluid supply drive module, including a peristaltic pump and dialysis tubing, is used to provide perfusion power for the infusion of dialysis fluid into the patient's peritoneal cavity; A non-contact end heating module is fitted onto the end of the dialysis tubing near the patient. The non-contact end heating module has a resonant cavity inside, and the dialysis tubing passes through the resonant cavity with a gap between it and the inner wall of the cavity. This module is used to perform non-contact electromagnetic eddy current micro-heating on the dialysis fluid in the tubing. A multi-dimensional signal sensing module is located downstream of the non-contact end heating module. It includes a high-frequency temperature sensor and a micro-pressure sensor, which are used to collect the end temperature signal of the patient's pre-peritoneal dialysis fluid and the hydraulic waveform signal in the pipeline in real time, respectively. The temperature-pressure coupling multi-state collaborative control module is communicatively connected to the liquid supply drive module, the non-contact end heating module, and the multi-dimensional signal sensing module, respectively; the collaborative control module is configured to perform the following operations: The temperature change rate is calculated based on the real-time collected end temperature signal. When the temperature change rate meets the preset cold stimulus negative drop condition, the output power of the non-contact end heating module is increased simultaneously and the infusion flow rate of the peristaltic pump is actively reduced to carry out cold stimulus spasm feedforward defense. The three-dimensional feature state is extracted from the real-time collected hydraulic waveform signal. Based on the frequency and amplitude fluctuation characteristics of the waveform, the pipeline state is identified as physiological breathing confirmation state, body position change disturbance resistance state, or real physical blockage state. The peristaltic pump is then linked to perform mechanical actions to maintain the original speed, suspend the instantaneous flow, or reverse to clear the blockage.

2. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 1, characterized in that, The liquid supply drive module includes: A bidirectional high-precision stepper motor and the pump head assembly connected to it; The control terminal of the stepper motor is electrically connected to the temperature-pressure coupling multi-state collaborative control module, and is used to receive and respond to the instantaneous flow suspension command to achieve millisecond-level braking and stopping, and to respond to the reverse unblocking command to output reverse rotation torque, thereby driving the pump head assembly to perform negative pressure back suction of the liquid in the dialysis pipeline.

3. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 2, characterized in that, The non-contact end heating module specifically includes: The outer shell has a hollow interior forming the resonant cavity; A high-frequency electromagnetic induction coil is embedded in the inner wall of the outer casing; A tubing limiting bracket is provided at both ends of the resonant cavity to suspend and fix the dialysis tubing on the central axis of the resonant cavity. In this system, an annular air gap with a constant radial width is formed between the outer wall of the fixed dialysis tubing and the high-frequency electromagnetic induction coil. The temperature-pressure coupling multi-state collaborative control module adjusts the frequency of the alternating current supplied to the high-frequency electromagnetic induction coil, so that the alternating magnetic field passing through the annular air gap directly excites eddy currents in the dialysate inside the dialysis tubing to generate heat.

4. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 3, characterized in that, The non-contact end heating module includes: A heat-insulating shielding layer is disposed on the outer surface of the outer shell to prevent electromagnetic radiation leakage and burns to patients due to excessively high outer surface temperature.

5. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 4, characterized in that, The non-contact end heating module also includes; The non-contact end heating module is spatially located at the point where the dialysis tubing is connected to the patient's abdominal catheter. At the end of the pipeline.

6. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 5, characterized in that, A medical-grade flexible fluid isolation membrane is provided between the micro-pressure sensor in the multi-dimensional signal sensing module and the dialysis tubing; The multidimensional signal sensing module also includes a front-end signal conditioning circuit connected to the high-frequency temperature sensor and the micro-pressure sensor. The front-end signal conditioning circuit is configured to perform hardware-level low-pass filtering and amplification on the acquired raw analog signal, and output a discrete-time end-temperature sequence signal after analog-to-digital conversion. With hydraulic waveform sequence signal ,in These are discrete-time sampling points.

7. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 6, characterized in that, The steps for determining the negative fall condition due to cold stimulation include: The temperature-pressure coupled multi-state collaborative control module receives the terminal temperature sequence signal. The exponential moving average algorithm is used for smoothing and denoising to obtain smoothed temperature values. The calculation formula is as follows: in, The preset smoothing coefficient, and ; Subsequently, within the preset sliding time window Calculate the real-time dynamic temperature change rate of the dialysate. The calculation formula is as follows: in, The number of sampling points within the sliding time window. The sampling period; when multiple consecutive sampling points When the threshold is less than the preset negative cold stimulation threshold, the cold stimulation spasm feedforward defense is triggered.

8. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 7, characterized in that, The specific calculation model for extracting the three-dimensional feature states of the hydraulic waveform signal acquired in real time is as follows: The temperature-pressure coupled multi-state collaborative control module converts discrete-time hydraulic waveform sequence signals. Decoupling to static intra-abdominal pressure components and dynamic alternating components ; The static intra-abdominal pressure component By setting the length to The moving average filter extraction is calculated using the following formula: The dynamic alternating component ; The collaborative control module controls the dynamic alternating components. Peak values ​​are extracted within a preset observation window, and dynamic amplitude characteristic values ​​are calculated. : in, Belongs to the current observation window; when When the waveform is in the first extreme value range and the zero-crossing rate matches the physiological breathing frequency range, it is determined to be in the physiological breathing confirmed state. when The first difference value is out of bounds and When it is in the second extreme value range, it is determined to be a positional mutation-resistant state; When the static intra-abdominal pressure component It exhibits a non-periodic, continuous monotonically increasing trend, and during this period When the value approaches zero, it is determined to be a true physical blockage state.

9. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 8, characterized in that, After triggering the cold stimulation spasm feedforward defense, the temperature-pressure coupled multi-state collaborative control module executes flow smoothing ramp-up logic based on temperature recovery: During the deceleration infusion, the collaborative control module continuously monitors the real-time dynamic temperature change rate. With the smoothed temperature value ; When satisfied And multiple consecutive sampling periods When all temperatures fall within the preset safe body temperature range, it is determined that the disturbance to the cold end environment of the pipeline has been eliminated and the risk of cold stimulation spasm has been relieved. At this point, the collaborative control module does not immediately restore the initial flow rate, but instead uses a smoothing curve algorithm to control the peristaltic pump's infusion flow rate within a preset buffer time window. The flow rate is gradually increased from a low level to a step-by-step or continuous increase until it returns to the initially set target perfusion flow rate.

10. The peritoneal dialysis fluid constant temperature supply and flow rate adaptive control system according to claim 9, characterized in that, When the temperature-pressure coupled multi-state collaborative control module determines that the pipeline state is a true physical blockage, it executes a self-healing and safety circuit-breaking logic based on retry counting to prevent false alarms. The specific steps are as follows: S1: Control the peristaltic pump to reverse the rotation a preset number of times to perform a retraction action, and record the number of retraction retries in the system register. Perform an increment operation; S2: After the aspiration action is completed, control the peristaltic pump to rotate forward and tentatively resume perfusion at a low speed, and extract the dynamic amplitude characteristic value within the current observation window again. With static intra-abdominal pressure component ; S3: If the waveform characteristics extracted a second time match the physiological respiration confirmation state, then it is determined that the tubing blockage has been successfully cleared, and the retry count is reset to zero. And restore the target perfusion flow rate; S4: If the waveform features extracted a second time are still determined to be a real physical blockage state, then repeat steps S1 to S3; when the number of retries... The preset maximum retry threshold has been reached. When the peristaltic pump is powered off and braked, the high-frequency alternating current of the non-contact end heating module is simultaneously cut off, and the audible and visual alarm module is activated to issue a manual intervention alarm.

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