Non-invasive blood pressure monitor dynamic pressure simulation calibration system

Abstract

This invention belongs to the field of medical metrology and testing technology. It discloses a dynamic pressure simulation calibration system for non-invasive blood pressure monitors, comprising: acquiring monitor model parameters, cuff specifications, and applicable populations; determining a basic operating condition set based on calibration procedures; extracting pulse morphology descriptors from a clinical blood pressure waveform feature library to construct a dynamic pressure target trajectory; activating the air pump and pulse volume adjustment unit to inject a composite air pressure signal conforming to the target trajectory into the cuff, while simultaneously acquiring actual pressure changes; comparing the actual pressure with the target trajectory frame by frame, identifying response deviations during the pressurization, stabilization, and deflation phases, and recording measurement delay, overshoot amplitude, and waveform distortion to form a dynamic response feature record; and combining the dynamic response features, displayed readings, static calibration, and airtightness test results to determine the dynamic scenario calibration conclusion of the monitor and generate a report. This improves the accuracy and clinical applicability of the calibration.

Description

Technical Field

[0001] This invention relates to the field of medical metrology and testing technology, and more specifically, to a dynamic pressure simulation calibration system for non-invasive blood pressure monitors. Background Technology

[0002] Existing calibration equipment generally lacks the ability to realistically simulate dynamic pressure processes, making it difficult to reproduce the complex changes in blood pressure fluctuations in clinical settings. Current dynamic calibration devices often employ simple linear pressure increase / decrease methods, resulting in a single waveform with gradual changes that fail to simulate the actual patterns of blood pressure changes in the human body. This leads to calibration results that do not fully reflect the monitor's performance in real-world usage scenarios. More critically, due to the lack of precise control and synchronous measurement of dynamic pressure waveforms, existing calibration methods cannot effectively assess issues such as measurement delay, overshoot, and waveform distortion during the monitor's dynamic response process. This results in a disconnect between calibration results and clinical reality, potentially directly impacting physician judgment and patient safety in clinical use.

[0003] In view of this, the present invention proposes a dynamic pressure simulation calibration system for non-invasive blood pressure monitors to solve the above problems. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art and to achieve the above objectives, the present invention provides the following technical solution: a dynamic pressure simulation calibration system for a non-invasive blood pressure monitor, comprising: Operating condition determination module: Obtain the model parameters, cuff specifications and applicable population categories of the non-invasive blood pressure monitor, and determine the basic operating condition set for this verification by combining the systolic blood pressure range, diastolic blood pressure range and heart rate range specified in the verification procedure; Target trajectory construction module: Based on the basic operating condition set, it calls the clinical blood pressure waveform feature library pre-installed in the tester to extract pulse morphology descriptors that match the selected population category; based on the pulse morphology descriptors, it constructs a dynamic pressure target trajectory that includes the steepness of the ascending limb, the position of the dicrotic notch, and the attenuation features of the descending limb. Signal injection and acquisition module: The built-in air pump and pulse volume adjustment unit of the calibrator are activated to inject a composite air pressure signal that conforms to the dynamic pressure target trajectory into the cuff cavity of the monitor; the actual pressure changes in the cavity are acquired simultaneously during the injection process; Response Deviation Analysis Module: Compares the actual pressure change with the dynamic pressure target trajectory frame by frame to identify the response deviation points of the monitor in the pressurization, stabilization and venting stages, and records the measurement delay, overshoot amplitude and waveform distortion to form a dynamic response characteristic record. Verification report generation module: Based on the dynamic response characteristic records and the monitor's displayed readings, combined with the static calibration results and airtightness test results, the module determines the verification conclusion of the monitor under dynamic usage scenarios and generates a verification report.

[0005] The technical effects and advantages of the non-invasive blood pressure monitor dynamic pressure simulation calibration system of this invention are as follows: This invention extracts pulse morphology descriptors matching the applicable population by calling a clinical blood pressure waveform feature library. Based on the steepness of the ascending limb, the position of the dicrotic notch, and the attenuation characteristics of the descending limb, a dynamic pressure target trajectory is constructed. This allows the calibration process to realistically reproduce the complex changes in clinical blood pressure fluctuations, avoiding the waveform uniformity problem caused by existing simple linear blood pressure rise and fall methods. Real blood pressure waveforms have typical characteristics such as rapid rise, peak duration, dicrotic notch, and exponential decay, which simple linear changes cannot represent. By mapping the real clinical waveform to a dynamic pressure trajectory for calibration through pulse morphology descriptors, the high degree of consistency between calibration conditions and clinical usage scenarios is ensured. Consistency: The air pump and pulse volume regulation unit work together to inject a composite air pressure signal into the cuff, achieving precise superposition of steady-state pressure and pulsating pressure. By comparing each beat, the system identifies the response deviation points of the monitor in each stage of pressurization, stabilization, and deflation, and records the measurement delay, overshoot amplitude, and waveform distortion, thus overcoming the shortcomings of existing methods in assessing dynamic response performance. The dynamic response characteristics are recorded and combined with the static calibration results for comprehensive judgment, ensuring that the verification conclusions can fully reflect the performance of the monitor in real dynamic scenarios, avoiding the disconnect between verification results and clinical practice, improving the accuracy and clinical applicability of the verification, and providing reliable protection for clinical safety. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the dynamic pressure simulation calibration system for the non-invasive blood pressure monitor of the present invention. Detailed Implementation

[0007] 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.

[0008] Example 1

[0009] Please see Figure 1 As shown, the non-invasive blood pressure monitor dynamic pressure simulation calibration system of this embodiment includes: Operating condition determination module: Obtain the model parameters, cuff specifications and applicable population categories of the non-invasive blood pressure monitor, and determine the basic operating condition set for this verification by combining the systolic blood pressure range, diastolic blood pressure range and heart rate range specified in the verification procedure.

[0010] Non-invasive blood pressure monitors are essential medical devices used in clinical practice for continuous monitoring of patients' blood pressure changes. Their measurement accuracy directly impacts doctors' diagnostic judgments and patient safety. Traditional calibration methods, employing static constant pressure approaches, can only verify the accuracy of the monitor's readings at fixed pressure points and cannot assess its response characteristics to dynamic blood pressure fluctuations in actual clinical use. Human blood pressure is not constant but pulsates periodically with each heartbeat. With each cardiac contraction, blood pressure rapidly rises to its peak systolic pressure and falls back to the diastolic baseline during diastole. This dynamic process contains rich waveform characteristics, such as the steepness of the ascending limb, dicrotic notch, and attenuation of the descending limb. These characteristics directly affect the monitor's measurement algorithm and response speed. Therefore, this invention constructs a dynamic pressure simulation environment that conforms to the real-world blood pressure fluctuation patterns to comprehensively calibrate the monitor, thus addressing the disconnect between existing calibration methods and clinical practice.

[0011] Before starting the verification, it is first necessary to determine the scope of the working conditions for verification, i.e., the basic operating condition set. The verification personnel read the model parameters from the nameplate or instruction manual of the non-invasive blood pressure monitor to be tested. The model parameters usually include information such as the device model, manufacturer, manufacturing date, and measurement range. The measurement range indicates the range of blood pressure that the monitor can measure. For example, in adult mode, the systolic blood pressure range is usually 60 to 260 mmHg, and the diastolic blood pressure range is 40 to 200 mmHg; in neonatal mode, the systolic blood pressure range is usually 40 to 130 mmHg, and the diastolic blood pressure range is 20 to 90 mmHg. At the same time, check the specifications of the cuffs that come with the monitor. The cuffs are divided into different sizes according to the applicable objects, such as newborn cuffs (arm circumference 6 to 11 cm), children's cuffs (arm circumference 11 to 19 cm), adult cuffs (arm circumference 22 to 32 cm), and large adult cuffs (arm circumference 32 to 42 cm). The cavity volume and air path impedance corresponding to different cuff specifications are different, which will affect the transmission characteristics of dynamic pressure waveforms. Therefore, it is necessary to record them accurately.

[0012] Based on the read model parameters and cuff specifications, the calibration personnel select the corresponding working mode in the calibration instrument's system settings interface. The calibration instrument has two preset typical modes: adult mode and neonatal mode, each corresponding to a different parameter space. Taking the adult mode as an example, according to the calibration regulations for "Sphygmomanometers and Blood Pressure Gauges" and the industry standard for "Non-invasive Automatic Blood Pressure Measurement Monitors," the systolic blood pressure calibration interval in adult mode is set to three typical points: 80 mmHg, 120 mmHg, and 160 mmHg; the diastolic blood pressure calibration interval is set to three typical points: 60 mmHg, 80 mmHg, and 100 mmHg; and the heart rate interval is set to three typical points: 60 beats / min, 75 beats / min, and 90 beats / min. These points cover common clinical conditions such as hypotension, normal blood pressure, hypertension, bradycardia, normal heart rate, and tachycardia. In neonatal mode, due to the physiological characteristics of newborns, the systolic blood pressure test range is adjusted to 50 mmHg, 70 mmHg, and 90 mmHg, the diastolic blood pressure test range is adjusted to 30 mmHg, 45 mmHg, and 60 mmHg, and the heart rate range is adjusted to 100 beats / min, 120 beats / min, and 140 beats / min, in order to adapt to the lower blood pressure level and faster heart rate characteristics of newborns.

[0013] It should be noted that the purpose of selecting three typical blood pressure levels—low, medium, and high—is to verify the consistency of the monitor's measurements across different blood pressure ranges. In clinical practice, monitors may face a wide range of pressures, from shock hypotension to hypertensive crisis, and calibration at only a single pressure point cannot detect range-related systematic errors. By evenly distributing calibration points within the candidate parameter space, the linearity and full-range accuracy of the monitor can be effectively evaluated.

[0014] The three parameters of systolic blood pressure, diastolic blood pressure, and heart rate are paired and combined to form multiple operating condition units. The specific combination method is as follows: First, a fixed pairing of systolic and diastolic blood pressure is established, for example, a systolic blood pressure of 120 mmHg paired with a diastolic blood pressure of 80 mmHg constitutes a normal blood pressure condition. Then, this blood pressure condition is paired with three heart rate values ​​to form three operating condition units: (120 / 80 mmHg, 60 bpm), (120 / 80 mmHg, 75 bpm), and (120 / 80 mmHg, 90 bpm). In this way, in adult mode, the three systolic blood pressure levels and three diastolic blood pressure levels can form nine blood pressure combinations. Each blood pressure combination is then paired with three heart rate levels, theoretically generating 27 operating condition units. However, considering the efficiency of testing and clinical practice, this embodiment selects 12 representative operating condition units as the basic operating condition set, including: low blood pressure and low heart rate (80 / 60 mmHg, 60 beats / min), low blood pressure and normal heart rate (80 / 60 mmHg, 75 beats / min), normal blood pressure and low heart rate (120 / 80 mmHg, 60 beats / min), normal blood pressure and normal heart rate (120 / 80 mmHg, 75 beats / min), normal blood pressure and high heart rate (120 / 80 mmHg, 90 beats / min), slightly hypertensive and normal heart rate (140 / 90 mmHg, 75 beats / min), hypertensive and normal heart rate (160 / 100 mmHg, 75 beats / min), and hypertensive and high heart rate (160 / 100 mmHg, 90 beats / min). These combinations cover the intersection of three blood pressure levels (low, medium, and high) and three heart rate levels, which can comprehensively examine the dynamic response characteristics of the monitor.

[0015] Each operating condition unit is assigned a cuff specification identifier and an applicable population category identifier. The cuff specification identifier is recorded as adult cuff or newborn cuff, etc. All paired operating condition units are arranged sequentially from low blood pressure to high blood pressure, and from low heart rate to high heart rate to form an operating condition sequence. Each operating condition unit is assigned a unique operating condition number, and the results are finally compiled into the basic operating condition set for this calibration. The basic operating condition set is stored in the internal memory of the calibration instrument in the form of a data table. The table includes fields such as operating condition number, systolic blood pressure setting value, diastolic blood pressure setting value, heart rate setting value, cuff specification, and applicable population category.

[0016] Target trajectory construction module: Based on the basic operating condition set, it calls the clinical blood pressure waveform feature library pre-installed in the calibration instrument to extract pulse morphology descriptors that match the selected population category; based on the pulse morphology descriptors, it constructs a dynamic pressure target trajectory that includes the steepness of the ascending limb, the position of the dicrotic notch, and the attenuation features of the descending limb.

[0017] The actual blood pressure waveform in the human body is not a simple sine wave or triangular wave, but a pulse waveform with complex physiological characteristics. A typical arterial blood pressure waveform includes the following features: During cardiac systole, the rapid ejection of blood from the left ventricle causes a sharp rise in aortic pressure, forming a steep ascending limb; after reaching the peak systolic pressure, the ejection velocity slows down, and the pressure curve shows a brief peak plateau; subsequently, the heart enters diastole, the aortic valve closes, and the pressure begins to decrease. During this decrease, due to the rebound effect of the aortic valve closure, a small indentation forms on the pressure curve, called the dicrotic notch or descending isthmus; thereafter, the pressure continues to decrease exponentially to the diastolic pressure baseline. These waveform characteristics contain important physiological information of the cardiovascular system and are also important bases for the blood pressure measurement algorithms of monitors. For example, oscillometric blood pressure measurement determines systolic and diastolic pressure by identifying changes in pulse wave amplitude during cuff pressure release. Therefore, if the pressure waveform applied during calibration differs too much from the actual blood pressure waveform, the monitor's measurement algorithm will malfunction or produce large errors, and the calibration results will not reflect the monitor's true performance.

[0018] This embodiment pre-loads a clinical blood pressure waveform feature library into the calibration instrument. The library was established as follows: A large amount of real patient arterial blood pressure waveform data was collected in the intensive care unit and cardiac catheterization laboratory of a clinical hospital using an invasive arterial blood pressure monitoring system (where a pressure sensor is directly inserted into the patient's artery for measurement). The data collected covered patient groups of different ages, genders, and disease types, including adult patients and newborns. After preprocessing such as noise reduction and baseline drift correction, the raw waveform data was jointly evaluated by clinical experts and biomedical engineers to select high-quality samples with clear waveforms and typical characteristics. Feature extraction was performed on the selected samples, describing the pulse waveform of each cardiac cycle using four key parameters: ascending limb slope, peak duration, dicrotic notch depth (percentage relative to the peak value), and descending limb time constant. These four parameters effectively characterize the morphological features of the pulse waveform. The samples were stored separately according to applicable population categories, with each category covering different individual differences and physiological states.

[0019] After determining the baseline operating conditions, the corresponding set of pulse samples is selected from the clinical blood pressure waveform feature database based on the applicable population category identifiers recorded therein. For example, if the current test object is an adult monitor, samples are extracted from the adult category of the feature database; if it is a neonatal monitor, samples are extracted from the neonatal category. There are significant differences between the blood pressure waveforms of adults and newborns, resulting in fundamentally different pulse waveform morphologies between the two population groups; therefore, samples must be extracted separately according to population category.

[0020] From the selected population sample set, the single-beat cycle length is determined based on the heart rate setting value of the current working unit. The single-beat cycle length is the duration of a complete cardiac cycle, and its calculation formula is as follows: ,in The single-shot cycle length (ms) This represents heart rate (beats / min), with a constant of 60000 as a unit conversion factor (60 × 1000 milliseconds). For example, when the heart rate is 75 beats / min, the single-beat cycle length is... Different heart rates directly affect the time scale of the pulse waveform. A faster heart rate results in shorter time for each cardiac cycle, compressing the waveform on the time axis; a slower heart rate stretches the waveform. Therefore, it is necessary to adapt the time axis of the standard samples extracted from the feature library. The time axis scaling adaptation method is as follows: assuming the baseline heart rate corresponding to the standard samples stored in the feature library is 75 beats / min (i.e., a single beat cycle of 800ms), and the current working condition heart rate is... When calculating the scaling factor .like A value less than 1 indicates that the current heart rate is faster than the baseline heart rate, and the waveform needs to be compressed on the time axis; if A value greater than 1 indicates that the current heart rate is slower than the baseline heart rate, requiring the waveform to be stretched on the time axis. Specifically, the rising slope of the standard sample is divided by a scaling factor to obtain the adapted rising slope. The peak duration and descent time constant are multiplied by the scaling factor to obtain the adapted duration parameters. The dicrotic notch depth is presented as a relative percentage and does not change with heart rate. After adaptation, these four parameters constitute the pulse morphology descriptor for the current operating condition, including... ,in The slope of the ascending branch after adaptation. This is the peak dwell time after adaptation. This refers to the depth of the diabetic notch. This is the time constant of the descent branch after adaptation.

[0021] It should be noted that the pulse morphology descriptor is not fixed, but rather adaptively adjusted according to operating parameters. This design can maintain the physiological authenticity of the waveform while adapting to the needs of different calibration conditions. In other embodiments, more parameters can be used to describe the pulse waveform, such as increasing the nonlinearity of the rising limb and the sharpness of the peak, to more finely characterize the waveform features.

[0022] Based on the acquired pulse morphology descriptor, a dynamic pressure target trajectory is constructed. The dynamic pressure target trajectory is the ideal pressure change curve that the calibration instrument needs to output during the calibration process. This curve simulates the cuff pressure change process actually encountered by the monitor in clinical use. The construction process is as follows: First, the diastolic pressure setting value in the current operating unit is used as the pressure baseline for a single beat, and the systolic pressure setting value is used as the baseline. As the peak pressure of a single shot. On the timeline, starting from time 0, the pressure rises from the baseline. Starting from the slope of the ascending branch in the pulse morphology descriptor It rises in the form of a linear or slightly convex curve, with a rise time of... Reaching peak Afterward, the pressure does not immediately decrease, but rather remains near the peak based on the duration of the peak, forming a flat-top segment. After the flat-top segment ends, the pressure begins to decrease, at which point a dilatation notch feature needs to be inserted into the descending channel. The specific method is as follows: first, starting from a certain descending slope... Descending to The location is the trough of the dicrotic notch, and the descent time is approximately... 20% to 30%; then the pressure rises back to The position forms the second small peak after the notch, and the recovery time is approximately... The pressure initially drops by 10% to 15%; then it continues to decrease. This process simulates the rebound fluctuations during aortic valve closure. Starting from the second small peak at the dicrotic notch, the pressure falls back to baseline in an exponentially decaying manner. The decay process follows the formula: ,in For the process The pressure of constant time This represents the elapsed time from the second minor peak. This exponential decay process simulates the natural decay of diastolic arterial pressure. When the pressure returns to baseline... When a complete single-beat pulse waveform is constructed, the total time taken is the length of the single-beat cycle. These single-beat waveforms are then continuously spliced ​​together according to the operating heart rate to form a multi-beat continuous pulse pressure sequence. For example, if the calibration process requires collecting at least 10 stable pulse cycles to assess the monitor's measurement stability, the single-beat waveforms are repeatedly spliced ​​10 times. During splicing, the starting baseline of the next beat coincides with the ending baseline of the previous beat to ensure the continuity of the pressure curve.

[0023] In addition to pulse ripple, the dynamic pressure target trajectory also includes the inflation and deflation processes during blood pressure measurement by the monitor. In clinical use, the typical measurement procedure for a monitor is as follows: first, the cuff is rapidly inflated to 30 to 40 mmHg above the estimated systolic pressure to completely block brachial artery blood flow; then, the cuff is slowly deflated at a rate of 2 to 3 mmHg / s, during which the pulse ripple of the cuff pressure is detected, and the systolic and diastolic pressures are determined by the change in the amplitude of the ripple; finally, the cuff is rapidly deflated to zero, completing one measurement. Therefore, a pre-inflation transition segment needs to be embedded before the multi-beat pulse sequence, and a stepped deflation transition segment needs to be embedded after the multi-beat sequence. The pre-inflation transition segment is constructed by rapidly increasing the pressure from atmospheric pressure (0 mmHg) at a rate of approximately 300 to 500 mmHg / s. The target pressure is set at mmHg, with a ramp-up time of approximately 0.3 to 0.5 seconds. Once the target pressure is reached, it is maintained for approximately 1 to 2 seconds to simulate the stabilization time after inflation on the monitor. The pressure then begins to decrease slowly at a rate set at 2.5 mmHg / s, consistent with clinically recommended deflation rates. During this decrease, the previously constructed multi-beat pulse waveform is superimposed on the slowly decreasing pressure baseline, forming a composite waveform of the decreasing baseline and pulse fluctuations. Specifically, the slowly decreasing baseline pressure is used as the diastolic pressure baseline for each beat, and this baseline is maintained every cardiac cycle. decline mmHg, pulse amplitude should be kept constant or adjusted appropriately according to physiological rhythms.

[0024] The stepped pressure relief transition section is designed as follows: when the pressure baseline drops to approximately 10 mmHg below the diastolic pressure setpoint, the superimposed pulse fluctuations cease, and the pressure rapidly deflates to 0 mmHg at a rate of approximately 500 mmHg / s, simulating the rapid venting process after the monitor measurement is completed. At this point, the complete dynamic pressure target trajectory is constructed, which includes: a pre-pressurization section, a pressure stabilization section, a venting measurement section, and a rapid pressure relief section.

[0025] It should be noted that the dynamic pressure target trajectory is stored in the form of a digital sequence, with a sampling frequency of no less than 100Hz (i.e., one sampling point every 10ms) to ensure accurate reproduction of waveform details, especially the accurate representation of high-frequency features such as the steep ascending segment and the dicrotic notch. In this embodiment, a sampling frequency of 200Hz is preferred, i.e., one sampling point every 5ms. For a heart rate of 75 beats / min and a single beat cycle of 800ms, each beat contains 160 sampling points, which can finely depict waveform details.

[0026] Signal injection and acquisition module: The built-in air pump and pulse volume adjustment unit of the calibrator are activated to inject a composite air pressure signal that conforms to the dynamic pressure target trajectory into the cuff cavity of the monitor; the actual pressure changes in the cavity are acquired simultaneously during the injection process.

[0027] After the dynamic pressure target trajectory is constructed, it needs to be converted into actual physical pressure and applied to the monitor cuff by the pneumatic actuator of the calibrator. The technical challenge of this process lies in providing the average pressure level required for blood pressure measurement (i.e., a slow release from high pressure to low pressure) while superimposing rapid pulse fluctuations simulating heartbeats on the average pressure. The time scale and amplitude scale of the two differ significantly, requiring precise pneumatic control to achieve.

[0028] The pneumatic system of the calibrator comprises two independent pressure sources: a built-in air pump as the base pressure source and a pulse volume control unit as the superimposed pressure source. The built-in air pump is a miniature brushless DC air pump with a rated output pressure of 300 mmHg and a flow rate range of 0 to 3 L / min. Its rotational speed is controlled via pulse width modulation, thereby regulating the output pressure. An electronically controlled proportional valve is connected to the air pump's output. This valve precisely adjusts the airflow opening based on a control signal, achieving fine control of the output pressure. The combination of the air pump and the proportional valve delivers a steady-state airflow carrying the average pressure to the cuff cavity. The average pressure is the pressure baseline in the dynamic pressure target trajectory, including high-pressure maintenance in the pre-pressurization phase, a slow descent in the deflation measurement phase, and rapid release in the rapid depressurization phase.

[0029] The pulse volume control unit (PWM) employs a piezoelectric ceramic-driven miniature plunger pump or a voice coil motor-driven piston pump. Its working principle is as follows: within a sealed, small-volume chamber, rapid driving of the piston or plunger generates volume changes, thus producing pressure pulses. This unit's response frequency can reach over 100Hz, enabling it to generate pulse fluctuations at corresponding frequencies in response to heart rate changes. The output of the PWM unit is connected to the main gas path via a thin tubing, with the connection point located after the proportional valve and before the cuff interface. The PWM unit operates by calculating the required gas volume to be released based on the pulse fluctuation amount (i.e., the difference between systolic and diastolic blood pressure) at each beat in the dynamic pressure target trajectory, according to the ideal gas law. ;in This refers to the pulse undulation. For cavity volume, This is the absolute pressure at standard atmospheric pressure (approximately 760 mmHg). For an adult cuff, the typical cavity volume is approximately 150 to 200 ml. When the pulse fluctuation is 40 mmHg, according to the ideal gas law, under near-atmospheric pressure operating conditions, the required volume change is approximately 7.9 ml. The piston stroke and drive voltage of the pulse volume control unit need to be precisely controlled to produce the corresponding volume change.

[0030] In actual operation, the main control unit of the calibration instrument performs time-coordinated control of the air pump and pulse rate adjustment unit. The main control unit pre-loads the dynamic pressure target trajectory into memory and reads the target pressure value point-by-point with a time step of 5ms (corresponding to a 200Hz sampling rate). For each time step: (1) Calculate the target baseline pressure at the current moment. That is, the average pressure component in the target trajectory after removing pulse fluctuations, in the pre-pressurization and stabilization phases. equal mmHg; in the venting measurement section It decreases linearly with time at a rate of 2.5 mmHg / s; during the rapid depressurization phase, It dropped rapidly to 0.

[0031] (2) Control the output of the air pump through a proportional valve to make the average pressure inside the cuff track the average pressure. Specifically, PID closed-loop control is used: the pressure sensor value inside the cuff is read in real time and compared with... The error is compared and calculated. Based on this error, the control voltage of the proportional valve is calculated using a PID algorithm to adjust the air path opening. The PID parameters are tuned based on the cuff volume and pipeline impedance. In this embodiment, the proportional coefficient is... Take 0.05V / mmHg as the integral coefficient. Take 0.02 V / (mmHg·s), differential coefficient Using 0.01 V·s / mmHg, this set of parameters can achieve a voltage regulation accuracy of ±1 mmHg and a response time of less than 100 ms under adult cuff conditions.

[0032] (3) Simultaneously, calculate the target pulse component at the current moment. This refers to the instantaneous value of high-frequency pulse fluctuations within the target trajectory. In the deflation measurement section, Equal to the pulse waveform value within the current beat; in the non-deflation measurement segment, It equals 0.

[0033] (4) According to rate of change Calculate the rate of volume change required by the pulse volume regulation unit. The relationship between the two is determined by the aerodynamic characteristics of the cuff cavity: ,in is the air pressure stiffness coefficient of the cuff, with dimensions in mmHg / ml. For adult cuffs, The value is approximately 5 to 7 mmHg / ml, and in this embodiment, it is 6 mmHg / ml. The required rate of volume change is achieved by controlling the frequency and amplitude of the drive signal of the pulse volume adjustment unit.

[0034] (5) The steady airflow output by the air pump and the pulsating airflow released by the pulse volume regulation unit are superimposed at the confluence point and enter the cuff cavity together, so that the pressure in the cavity contains both the slowly changing baseline component and the rapidly changing pulse component. The actual pressure curve after the superposition of the two is the composite air pressure signal, which should be highly consistent with the dynamic pressure target trajectory.

[0035] It should be noted that the control cycle of both the air pump and the pulse volume regulation unit is 5ms, synchronized with the sampling cycle of the target trajectory. This synchronization mechanism ensures the real-time performance of pressure control. A dedicated timer is set in the main control unit, triggering a control interrupt every 5ms. The above calculations and outputs are completed in the interrupt service routine. The interrupt response time is less than 50μs, which is much smaller than the 5ms control cycle, ensuring the determinism of control.

[0036] During the injection of the composite pneumatic signal, the actual pressure changes within the cuff cavity need to be collected simultaneously to assess the accuracy of the calibrator's output and provide a data basis for subsequent deviation analysis. At the connection interface between the cuff cavity and the calibrator, the calibrator extends an independent sensing branch, implemented using a three-way connector: one path connects to the pneumatic pump and pulse volume control unit's air supply output; another path connects to the cuff of the monitor under test; and the third path connects to the calibrator's standard pressure sensor. This three-way connection ensures that the pressure value measured by the standard pressure sensor is consistent with the pressure value within the monitor's cuff.

[0037] The standard pressure sensor selected is a high-precision pressure sensor that meets the requirements of the "Verification Procedure for Digital Pressure Gauges". In this embodiment, a diffused silicon piezoresistive pressure sensor is selected. This type of sensor has the characteristics of fast response speed, good linearity and high temperature stability, and can accurately capture rapidly changing pulse pressure signals.

[0038] The output signal of the pressure sensor is processed by a signal conditioning circuit. This circuit includes: a preamplifier circuit to amplify the sensor's weak voltage signal to the input range of the analog-to-digital converter (ADC); a low-pass filter circuit to filter out 50Hz power frequency interference and high-frequency noise, with a cutoff frequency set to 50Hz, effectively filtering out interference while retaining the main frequency components of the pulse signal (heart rate of 60 to 150 beats / min corresponds to frequencies of 1 to 2.5Hz); and a voltage follower to increase the circuit's input impedance and reduce the load effect on the sensor. The conditioned signal is then sent to a high-precision ADC for analog-to-digital conversion. This embodiment uses a 24-bit high-precision ADC with an effective resolution of over 20 bits. For a 300mmHg range, the minimum resolvable pressure change is approximately 0.0003mmHg, fully meeting the calibration requirements.

[0039] The analog-to-digital converter's sampling frequency is set to 200Hz, consistent with the sampling frequency of the dynamic pressure target trajectory. The sampling time is uniformly triggered by the main control unit's timer, sharing the same clock source with the control times of the air pump and pulse rate adjustment unit, achieving strict time synchronization. The importance of this synchronization mechanism lies in the fact that only when the sampling and control times are strictly aligned can the time delay between the control output and the actual response be accurately assessed; if sampling and control are asynchronous, additional phase errors will be introduced, affecting the assessment of dynamic response characteristics. A temperature-compensated crystal oscillator (TCXO) is used as the clock source to ensure time accuracy during long-term operation.

[0040] The collected pressure data is tagged and stored using a three-level index: "Operating Condition Unit Number - Beat Sequence Number - Sampling Time". The operating condition unit number corresponds to the operating condition number in the basic operating condition set, such as Operating Condition 1, Operating Condition 2, etc.; the beat sequence number indicates which beat of the pulse under that operating condition the current data belongs to, counting from 1; the sampling time records the cumulative time from the start of that operating condition to the current sampling point, in milliseconds. The advantage of using a three-level index is that it facilitates subsequent data retrieval and analysis. For example, it allows for the rapid extraction of the complete waveform data of the 5th beat under a specific operating condition, or the comparison of pressure levels for the same beat under different operating conditions. Data storage employs a circular buffer mechanism with a buffer size set to 10MB. The storage medium is high-speed SRAM, offering fast read and write speeds. After a power outage, data can be retained for 30 minutes via a backup battery, ensuring no data loss during abnormal power failures.

[0041] It should be noted that the connection between the calibrator and the monitor under test uses a standard endotracheal interface to reduce the impact of aerodynamic inertia and volumetric effects on pressure transmission. Before connection, the tubing must be checked for leaks, twisting, blockages, or other issues.

[0042] Response Deviation Analysis Module: Compares the actual pressure change with the dynamic pressure target trajectory frame by frame to identify the response deviation points of the monitor during the pressurization, stabilization and venting stages, and records the measurement delay, overshoot amplitude and waveform distortion to form a dynamic response characteristic record.

[0043] After collecting the actual pressure changes within the cuff, it is necessary to compare and analyze them with the preset dynamic pressure target trajectory to evaluate the accuracy of the calibrator output and the dynamic response characteristics of the monitor. Since the human blood pressure measurement process can be divided into three stages: boosting, stabilizing, and deflating, the working state and performance requirements of the monitor are different in different stages. Therefore, it is necessary to perform deviation analysis in each stage.

[0044] First, the actual pressure change data is divided into stages. Based on the rate characteristics of pressure change, the boundaries of each stage can be automatically identified: the pressure rise stage is characterized by a pressure rise rate greater than 100 mmHg / s and a duration of 0.3 to 0.5 seconds. By finding the time period that meets this condition, the start time of the pressure rise stage is determined. and end time The pressure stabilization phase is characterized by the pressure being maintained within the target high pressure range of ±5 mmHg for 1 to 2 seconds, thus determining the start time of the pressure stabilization phase. (coinciding with the end of the boost phase) and the end time The venting phase is characterized by a pressure decrease at a rate of 2 to 5 mmHg / s for a duration of 10 to 20 seconds; the start time of the venting phase should be determined. (coinciding with the end of the voltage stabilization phase) and the end time The rapid depressurization phase is not included in the dynamic response analysis.

[0045] During the pressurization phase, the focus is on the rate of increase of the monitor cuff pressure and the time it takes to reach the target pressure. After the calibrator starts the air pump, the cuff pressure should rise rapidly. However, due to factors such as cuff cavity volume, tubing impedance, and air pump power, the actual pressurization rate may differ from the target trajectory. If the pressurization rate is too slow, it will prolong the measurement time and increase patient discomfort; if the pressurization rate is too fast, it may cause pressure overshoot, damaging the cuff or affecting measurement accuracy. In this embodiment, the evaluation index for pressurization performance is set as "the actual pressure first reaches the target high pressure (…)". The time difference between "the moment when the target pressure reaches the target high pressure" and "the moment when the target trajectory reaches the target high pressure" is the measurement delay during the pressure boosting phase. The specific identification method is as follows: set the threshold value for the target high pressure to be... mmHg, locate the moment in the target trajectory when the pressure first reaches or exceeds this threshold value. Find the moment in actual pressure data when the pressure first reaches or exceeds this threshold value. Calculate the time difference .like A value greater than 0 indicates that the actual voltage increase is slower than the target, indicating a voltage increase delay; if... A value less than 0 indicates that the actual pressure rise is faster than the target, which may pose a risk of overshoot; ideally... It should be within ±50ms. This embodiment will... Cases exceeding 100ms are recorded as boost response deviation points, and the time of these deviation points is recorded as follows: The deviation is recorded as .

[0046] During the stabilization phase, the focus is on pressure stability and the presence of overshoot. Overshoot refers to the phenomenon where the pressure exceeds the target value during its rise and then falls back. Excessive overshoot can lead to excessive pressure from the cuff on the limb, causing pain and even damage to blood vessels or nerves. The overshoot amplitude is defined as the maximum value of the actual pressure during the stabilization phase. With target high pressure The difference between mmHg, i.e. Under normal circumstances, due to the derivative action and inertia effect of PID control, a small overshoot is permissible, but the overshoot amplitude should be controlled within 5 mmHg. This embodiment will... A reading greater than 8 mmHg is recorded as the overshoot deviation point, and the time of the deviation point is recorded as follows: At the corresponding moment, the overshoot amplitude was recorded as follows: Furthermore, pressure fluctuations need to be assessed during the stabilization phase. Ideally, the pressure should be maintained at a certain level. If the pressure fluctuation is too large within the mmHg range, it indicates that the gas path control is unstable, which may affect the pulse wave detection in the subsequent venting stage. In this embodiment, the standard deviation of the pressure during the pressure stabilization stage is calculated. If the standard deviation is greater than 3 mmHg, it is recorded as the pressure stabilization fluctuation deviation point.

[0047] During the deflation phase, the focus of the analysis is the fidelity of the pulse waveform. The deflation phase is crucial for blood pressure measurement by the monitor. The monitor determines systolic and diastolic blood pressure by detecting the change in pulse amplitude with the deflation pressure, therefore, the shape of the pulse waveform directly affects the measurement results. If the pulse waveform output by the calibrator differs significantly from the target trajectory, it can cause the monitor's oscillation wave recognition algorithm to malfunction or produce large errors. The degree of waveform distortion is assessed using a beat-by-beat comparison method. The actual pressure data and target trajectory data during the deflation phase are divided into individual pulse beats according to the cardiac cycle, with each beat's segmentation point being a local minimum of the diastolic blood pressure baseline. For each beat, the following characteristic parameters are extracted: pulse amplitude (the difference between the peak systolic blood pressure and the diastolic blood pressure baseline), rise time (the time taken to rise from the baseline to the peak), fall time (the time taken to fall from the peak back to the baseline), and dicrotic notch depth (the difference between the trough and the peak of the dicrotic notch). Calculate the relative error between the actual and target beats for the corresponding characteristic parameters: the ratio of the absolute value of the difference between the actual and target values ​​to the target value; calculate the weighted average of the four relative errors to obtain the waveform distortion index for a single beat. The weighting coefficients are determined based on the degree of influence of each parameter on blood pressure measurement. In this embodiment, the weights are 0.4, 0.2, 0.2, and 0.2, indicating that pulse amplitude is the most important feature (because oscillometric measurement is based on amplitude envelope), and other features are secondary. If the waveform distortion index of a certain beat is greater than 0.15 (i.e., the distortion exceeds 15%), then the beat is recorded as a waveform distortion deviation point, and the beat number, time, and distortion value are recorded.

[0048] It should be noted that waveform distortion may be caused by insufficient output accuracy of the calibrator, nonlinear transmission characteristics of the cuff-limb system, or frequency response limitations of the monitor's internal sensors. Data collected by the calibrator's own pressure sensor assesses the signal quality at the calibrator's output. To further evaluate the monitor's response characteristics, the real-time pressure waveform displayed on the monitor (read via the communication interface) can be compared with the calibrator's standard pressure.

[0049] The time delay of the pressure boost response deviation point, the overshoot amplitude and standard deviation of the pressure stabilization fluctuation during the pressure stabilization phase, and the waveform distortion of each step during the venting phase are summarized to form a dynamic response characteristic record of the current operating condition.

[0050] For each condition in the baseline operating condition set, the above analysis process is repeated to ultimately generate a complete dynamic response characteristic record table. This table visually reflects the dynamic response performance of the monitor under different blood pressure levels and heart rate conditions, and is an important basis for evaluating whether the monitor is suitable for clinical dynamic measurement scenarios.

[0051] It should be noted that the identification of deviation points is achieved using an automatic algorithm, but the calibration software also provides a manual verification function. Calibrators can view a comparison chart of the actual pressure curve and the target trajectory via a touchscreen to confirm or correct the automatic identification results. In other embodiments, the Dynamic Time Warping (DTW) algorithm can also be used to calculate the overall similarity between the actual waveform and the target waveform as a supplementary evaluation index for waveform distortion.

[0052] Verification report generation module: Based on the dynamic response characteristic records and the monitor's displayed readings, combined with the static calibration results and airtightness test results, the module determines the verification conclusion of the monitor under dynamic usage scenarios and generates a verification report.

[0053] After completing the dynamic pressure simulation verification, it is necessary to comprehensively analyze the verification data from multiple aspects to determine the overall performance of the monitor and issue a formal verification report. The monitor's performance includes not only dynamic response characteristics but also static measurement accuracy, airtightness, and deflation rate, among other aspects. Only when all indicators meet the requirements can it be deemed qualified. Before conducting the dynamic pressure simulation verification, the monitor first performs static calibration and airtightness testing, which are fundamental verification items. The purpose of static calibration is to verify the monitor's indication error under constant pressure. After the monitor enters static calibration mode, a series of preset constant pressure values ​​are applied to the cuff via an air pump. Typically, six verification points are selected: 0 mmHg, 60 mmHg, 100 mmHg, 150 mmHg, 200 mmHg, and 250 mmHg, covering the entire measurement range of the monitor. For each calibration point, the calibration instrument stabilizes the cuff pressure within the target value of ±1 mmHg for 30 seconds. After the pressure stabilizes, the display value of the standard pressure sensor on the calibration instrument and the pressure reading on the monitor's display screen are simultaneously read, and the indication error is calculated. According to regulations, the maximum permissible error of the monitor is ±3 mmHg. If the indication error at any of the six calibration points exceeds 3 mmHg, the static calibration fails. In this embodiment, the measurement is repeated three times, and the average value is taken as the indication error to reduce the influence of random errors.

[0054] The purpose of the airtightness test is to verify the sealing performance of the cuff and connecting air circuit. If leakage is present, it will cause a slow pressure drop during measurement, affecting measurement accuracy and, in severe cases, preventing the measurement from being completed. The calibration method is as follows: pressurize the cuff to 170±5 mmHg (this value is the specified test pressure, located in the middle of the measurement range). After pressurization, close the air pump and exhaust valve of the calibration instrument to ensure the air circuit is sealed. Maintain this for 60 seconds and observe the pressure drop of the cuff. According to the procedure, the pressure drop within 60 seconds should not exceed 6 mmHg. If the drop is greater than 6 mmHg, it indicates a significant air leak, and the airtightness test fails.

[0055] In addition to static calibration and airtightness, the deflation rate also needs to be tested. The deflation rate refers to the speed at which the monitor controls the cuff pressure decrease during measurement. According to standards, the recommended deflation rate is 2 to 3 mmHg / s. Too fast a rate will result in insufficient pulse counts, affecting measurement accuracy; too slow a rate will prolong measurement time and increase patient discomfort. The calibration method is as follows: inflate the cuff to 200 mmHg, start the monitor's measurement program to enter the automatic deflation phase, record the time required for the pressure to decrease from 180 mmHg to 80 mmHg (a pressure difference of 100 mmHg), and calculate the deflation rate. A deflation rate within the range of 2 to 5 mmHg / s is considered acceptable.

[0056] After completing the above basic verification items, proceed to dynamic pressure simulation verification, following steps S1-S4 to obtain dynamic response characteristic records. Simultaneously, during the dynamic verification process, record the final blood pressure measurement results displayed by the monitor. For each operating condition, the monitor will display a set of measurements after the deflation phase, including systolic blood pressure, diastolic blood pressure, and heart rate. Compare the measured values ​​displayed by the monitor with the set values ​​for the operating condition to calculate the error; according to the standard, the permissible error for blood pressure measurement is ±5 mmHg or more stringently ±3 mmHg (depending on the accuracy class claimed by the device), and the permissible error for heart rate measurement is ±3 beats / min or ±5%, whichever is greater.

[0057] The deviation indicators in the dynamic response characteristic record table are compared with the allowable limits of the procedure. The dynamic performance allowable limits recommended in this embodiment are: measurement delay. overshoot amplitude During the pressure stabilization phase, the pressure standard deviation must be less than or equal to 3 mmHg, and the waveform distortion must be less than or equal to 15%. If any dynamic indicator exceeds the allowable limit for any operating condition, that operating condition is marked as "Dynamic Item Unqualified". The results of the dynamic item judgment, static calibration judgment, airtightness judgment, and venting rate judgment are summarized by operating condition to form a comprehensive judgment column. If the comprehensive judgment for all operating conditions is "qualified", the monitor is judged as "calibrated qualified" as a whole. If the comprehensive judgment for any operating condition is "unqualified", the monitor is judged as "calibrated unqualified" as a whole, requiring adjustment, repair, or replacement before recalibration.

[0058] Based on the above analysis results, a formal verification report is generated. The verification report adopts a standard format, conforms to the requirements of the "National Metrological Verification Procedure Compilation Rules," and includes the following main contents: 1. Report header information: Name, address, and contact information of the verification unit; verification certificate number; verification date; verification location; environmental conditions (temperature, humidity, atmospheric pressure). Environmental conditions should meet the following requirements: temperature 15 to 35°C, relative humidity 25% to 85%, atmospheric pressure 86 to 106 kPa. In this example, the verification environment is: temperature 23°C, relative humidity 55%, atmospheric pressure 101.3 kPa.

[0059] 2. Information on the device under inspection: Device name (non-invasive blood pressure monitor), model and specifications, manufacturer, serial number, submitting unit, device status, etc. For example: Model PM-9000, manufacturer: [Name of Medical Device Company], serial number: 202301001, submitting unit: [Name of Hospital], device status: normally operating.

[0060] 3. Verification Basis: List the technical documents on which this verification is based, including the "Verification Procedure for Non-invasive Automatic Blood Pressure Monitors (Electronic Blood Pressure Monitors)" and the "Non-invasive Automatic Blood Pressure Monitor" standard.

[0061] 4. Standard instruments and supporting equipment used for verification: List the name, model, measurement range, accuracy class, certificate number, and validity period of the verification instrument.

[0062] 5. Verification Items and Results: Appearance and Power-on Inspection: The equipment is inspected for undamaged appearance, normal display, normal button functions, intact cuff, no rupture or aging of the trachea, and normal indicator lights after power-on; it is deemed qualified. Static Indication Error: A data table is provided for the six verification points, along with the maximum indication error and judgment result. Air Tightness: Initial pressure, holding time, pressure drop, and judgment result are provided. Deflator Rate: Start and stop pressure, time, calculation rate, and judgment result are provided. Dynamic Pressure Response Characteristics: The set parameters of the basic operating condition set are listed, and a dynamic response characteristic record table is provided. Blood Pressure Measurement Accuracy: A comparison table of the monitor readings and set values ​​under various operating conditions is provided, along with the maximum error and judgment result for systolic blood pressure, diastolic blood pressure, and heart rate.

[0063] 6. Verification Conclusion: Clearly state "After verification, the equipment meets the requirements and is qualified" or "After verification, the equipment fails to meet the requirements for a certain item and is unqualified." For unqualified items, the conclusion must be clearly stated, such as "Static indication error exceeds the allowable range," etc.

[0064] The calibration report is displayed in real time on the calibration instrument's color touchscreen. Calibrators can view various data and charts on the screen and make necessary annotations and modifications. After the report is confirmed to be correct, it can be exported as a PDF for printing and archiving via the calibration instrument's communication interface, or uploaded to the calibration management system via the network to achieve information-based management of calibration data.

[0065] It should be noted that the verification method of this invention, while retaining basic verification items such as traditional static calibration, adds dynamic pressure response characteristic verification, which is an important supplement to existing verification methods. Traditional methods can only verify the accuracy of the monitor under static constant pressure, while dynamic verification can evaluate the monitor's measurement performance under simulated real blood pressure fluctuations, including its ability to recognize pulse waveforms, dynamic response speed, and anti-interference ability, which is closer to actual clinical use scenarios. Problems discovered through dynamic verification are often those that cannot be detected by static verification, such as waveform distortion caused by improper digital filtering algorithms of the monitor, missed pulse detection due to insufficient sampling frequency, and dynamic errors caused by insufficient frequency response of the pressure sensor. Therefore, the verification method of this invention can more comprehensively and accurately evaluate the overall performance of the monitor, which is of great significance for ensuring the accuracy of clinical blood pressure monitoring and patient safety.

[0066] In summary, the dynamic pressure simulation calibration method for non-invasive blood pressure monitors proposed in this invention constructs a dynamic pressure target trajectory that conforms to the characteristics of real blood pressure fluctuations. It utilizes a composite pneumatic system of an air pump and pulse volume regulation unit to accurately output composite pressure signals, simultaneously acquiring and analyzing actual pressure responses. This comprehensively evaluates the dynamic performance of the monitor in each stage of pressurization, stabilization, and deflation. Combined with traditional calibration items such as static calibration and airtightness, a complete calibration system is formed, effectively solving the problem of existing calibration methods being disconnected from clinical practice. This improves the clinical applicability of calibration results and provides technical assurance for ensuring the accuracy of blood pressure monitoring and patient safety. This solution is applicable to the calibration and verification of various non-invasive blood pressure monitors, including desktop monitors, portable monitors, and ambulatory blood pressure monitors, and has broad application value.

[0067] It should be noted that the parameter settings in this embodiment are recommended values ​​determined based on clinical practice and technical standards. Implementers can adjust these values ​​according to the specific testing object, testing purpose, and standard requirements. For example, the number of conditions in the basic test case set can be selected between 6 and 27 to balance testing efficiency and coverage; the sampling frequency of the dynamic pressure target trajectory can be selected between 100 and 500 Hz based on waveform complexity; and the allowable limits for dynamic performance can be appropriately relaxed or tightened according to the equipment's accuracy level. The core of this invention lies in the technical concept and implementation method of dynamic pressure simulation. The setting of specific parameters is a conventional technical means that can be flexibly adjusted by those skilled in the art according to actual needs. Contents not described in detail in this specification are prior art known to those skilled in the art and will not be elaborated upon here.

[0068] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dynamic pressure simulation calibration system for a non-invasive blood pressure monitor, characterized in that, include: Operating condition determination module: Obtain the model parameters, cuff specifications and applicable population categories of the non-invasive blood pressure monitor, and determine the basic operating condition set for this verification by combining the systolic blood pressure range, diastolic blood pressure range and heart rate range specified in the verification procedure; Target trajectory construction module: Based on the basic operating condition set, it calls the clinical blood pressure waveform feature library pre-installed in the tester to extract pulse morphology descriptors that match the selected population category; based on the pulse morphology descriptors, it constructs a dynamic pressure target trajectory that includes the steepness of the ascending limb, the position of the dicrotic notch, and the attenuation features of the descending limb. Signal injection and acquisition module: The built-in air pump and pulse volume adjustment unit of the calibrator are activated to inject a composite air pressure signal that conforms to the dynamic pressure target trajectory into the cuff cavity of the monitor; the actual pressure changes in the cavity are acquired simultaneously during the injection process; Response Deviation Analysis Module: Compares the actual pressure change with the dynamic pressure target trajectory frame by frame to identify the response deviation points of the monitor in the pressurization, stabilization and venting stages, and records the measurement delay, overshoot amplitude and waveform distortion to form a dynamic response characteristic record. Verification report generation module: Based on the dynamic response characteristic records and the monitor's displayed readings, combined with the static calibration results and airtightness test results, the module determines the verification conclusion of the monitor under dynamic usage scenarios and generates a verification report.

2. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 1, characterized in that, The methods for determining the basic operating condition set include: Read the model parameters and range markings on the nameplate of the non-invasive blood pressure monitor. Select the corresponding adult mode or neonatal mode from the calibration instrument system settings interface, and retrieve the systolic blood pressure range, diastolic blood pressure range, and heart rate range in that mode as candidate parameter space. Within the candidate parameter space, select representative parameter points according to three typical blood pressure levels: low, medium, and high. Pair each representative parameter point with the low, medium, and high heart rate values ​​within the heart rate range to form multiple operating condition units. Arrange the multiple operating condition units in the calibration order, and add cuff specification markings and applicable population category markings to each operating condition unit. Finally, summarize them into a basic operating condition set.

3. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 2, characterized in that, Methods for obtaining pulse morphology descriptors include: The clinical blood pressure waveform feature library stores typical pulse samples for two major population groups: adults and newborns. Each pulse sample is described by four indicators: the slope of the ascending limb, the duration of the peak, the depth of the dicrotic notch, and the time constant of the descending limb. Based on the applicable population category identifier in the baseline work condition set, the pulse sample set of the corresponding population is selected from the feature library. Then, the single beat cycle length is determined according to the heart rate value of the current work condition unit, and the selected pulse samples are scaled and adapted on the time axis. Finally, a pulse morphology descriptor containing the four indicators is output.

4. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 3, characterized in that, Methods for constructing dynamic pressure target trajectories include: Using the diastolic blood pressure parameter in the current working condition unit as the single-beat baseline and the systolic blood pressure parameter as the single-beat peak, the transition segment from the baseline to the peak is determined based on the slope of the ascending branch in the pulse morphology descriptor; a brief flat-top segment is formed at the peak based on the peak dwell time; a secondary small peak feature is inserted in the descending channel based on the depth of the dicrotic notch; finally, an attenuation segment from the peak back to the baseline is generated based on the descending branch time constant; multiple consecutive beats are spliced ​​according to the working condition heart rate, and a pre-inflation transition segment of the cuff being fully inflated to the upper limit of the working condition systolic blood pressure and a stepped deflator transition segment of the deflation stage are embedded at the splicing point to form a dynamic pressure target trajectory.

5. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 4, characterized in that, Injecting a composite pneumatic signal conforming to the dynamic pressure target trajectory into the monitor cuff cavity, including: The built-in air pump serves as the basic pressure source, responsible for delivering a steady-state airflow carrying the average pressure to the cuff cavity. The pulse volume adjustment unit serves as the superimposed pressure source, releasing minute gas disturbances step by step according to the single-beat fluctuation in the dynamic pressure target trajectory. During the gas injection process, the main control unit of the calibrator coordinates the timing of the air pump output pressure and the release amount of the adjustment unit, so that the intracavitary pressure curve after the superposition of the two matches the dynamic pressure target trajectory. At the same time, a high-precision pressure sensing channel is set on the cavity side to synchronously record the actual pressure changes with a sampling beat tens of times higher than the pulsation frequency.

6. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 5, characterized in that, During the injection process, the actual pressure changes within the cavity are simultaneously collected, including: An independent sensing branch is led out at the connection interface between the cuff cavity and the calibrator. A pressure sensing element that meets the accuracy level requirements of the calibrator is set on the sensing branch. The output signal of the pressure sensing element is processed by an amplification circuit and an anti-interference filter circuit and then sent to the sampling module. The sampling module continuously records according to the synchronization time mark issued by the main control unit. The synchronization time mark and the release beat of the pulse volume adjustment unit share the same clock source. The actual pressure sequence output by the sampling module is stored in the internal storage area of ​​the calibrator according to the beat, and is indexed by the working condition unit number, beat number and sampling time in a three-level index.

7. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 6, characterized in that, Methods for identifying response deviations include: The actual pressure change is divided into three stages: pressure increase, pressure stabilization, and venting. Within each stage, a point-by-point comparison is made with the corresponding segment of the dynamic pressure target trajectory. In the pressure increase stage, the difference between the moment when the actual pressure first reaches the target trajectory threshold and the moment when the target trajectory reaches the same threshold is compared, and the point where the difference is not zero is recorded as the pressure increase response deviation point. In the pressure stabilization stage, the point where the actual pressure exceeds the peak value of the target trajectory is recorded as the overshoot deviation point. In the venting stage, the period when the actual pressure fall rate does not match the time constant of the target trajectory descent is recorded as the venting deviation point.

8. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 7, characterized in that, The methods for obtaining dynamic response feature records include: The time difference of the pressure rise response deviation point is organized into a measurement delay item; the instantaneous difference of the overshoot deviation point is organized into an overshoot amplitude item; the beat-by-beat difference between the actual pressure and the target trajectory within the corresponding time period of the venting deviation point is organized into a waveform distortion degree item; the three items are bound to the current working condition unit number to form a dynamic response characteristic record item under a single working condition; after traversing all working condition units in the basic working condition set, all characteristic record items are summarized in the order of working condition number to form a complete dynamic response characteristic record table.

9. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 8, characterized in that, The methods for obtaining static calibration results and airtightness test results include: Before the dynamic pressure simulation verification begins, the calibrator first enters the static calibration mode, applying preset constant pressure values ​​at multiple levels to the cuff cavity of the non-invasive blood pressure monitor. The deviation between the monitor's displayed reading at each pressure level and the reading of the calibrator's sensor channel is recorded to form the static calibration result. Then, the airtightness test mode is entered, the cuff cavity is pressurized to the test pressure specified in the procedure, and the air passage is closed. The pressure drop inside the cavity is observed within the specified holding time to form the airtightness test result. Both results, along with the deflation rate test result, are stored in the calibrator's storage area for later use.

10. The dynamic pressure simulation calibration system for non-invasive blood pressure monitors according to claim 9, characterized in that, Methods for obtaining the inspection report include: The measurement delay, overshoot amplitude, and waveform distortion levels in the dynamic response characteristic record table are compared with the corresponding allowable limits in the verification procedure. Any operating unit that exceeds the allowable limit in any of these items is marked as unqualified in the dynamic item. The deviations of each level in the static calibration results and the pressure drop in the airtightness test results are compared with the limit values ​​in the procedure, and the qualified status of the static item and the sealing item is marked. The above marks are summarized by operating unit to form a comprehensive judgment column. The basic operating condition set, dynamic pressure target trajectory parameters, dynamic response characteristic record table, and comprehensive judgment column are written into the verification report, which is displayed on the color touch screen of the verification instrument and output through the communication interface.

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