60 results about "Pulse pressure" patented technology

The invention provides a low-rank personalized blood pressure estimation method, which comprises the following steps of: performing pre-training on a large-scale PPG-blood pressure data pair on a group level based on a UniTS model of a Transform backbone network, and learning a mapping relation from a PPG signal to blood pressure; carrying out personalized fine tuning on the pre-trained model by adopting a low-rank adaptive technology to realize model adaptation under the condition of few samples; in the personalized fine tuning process, a pulse pressure segmented penalty loss function is introduced, total training loss is formed by combining mean square error loss, and prediction results of the systolic pressure and the diastolic pressure are restrained to conform to the physiological law; the problem of sampling rate difference is solved by adopting a low-rank self-adaptive method with a stable sampling rate, and stable blood pressure estimation across equipment is realized; the invention aims to realize high-precision and cross-device robust blood pressure estimation according with physiological rules under the condition of few-sample calibration by introducing a physiological constraint loss function and sampling rate robust adaptation mechanism only depending on PPG signals and through a framework combining group pre-training and low-rank personalized fine tuning.

The invention provides a fetal hypoxia early risk identification method and system based on a large pulse pressure phenotype, and relates to the technical field of biomedical signal processing and heart sound signal analyse.The method comprises the steps that fetal heart sound signals and body surface vibration signals at the abdominal wall of a pregnant woman are collected through a multi-channel sensing array; a preprocessing means is adopted to improve the signal-to-noise ratio of a target signal and suppress an interference signal; in the sliding time window, a large pulse pressure phenotypic feature set and heart sound time phase parameters are extracted; based on the combined criterion, fetal hypoxia risk judgment is carried out; and outputting the graded early warning information, and supporting the playback of the risk event fragment. According to the method, fetal real heart sound mechanical vibration serves as an information source, hypoxia early warning is achieved based on a large pulse pressure phenotype, individualized base lines (including day and night layering) and gestational week self-adaptive correction are supported, the anti-interference capacity is high, the 7 * 24-hour continuous monitoring requirement in a hospital / family can be met, and the sensitivity and specificity of hypoxia recognition are improved.

The invention relates to the technical field of clinical decision support and medical data intelligent analysis, in particular to a critical patient individualized liquid resuscitation decision support system, which is characterized in that a data acquisition unit acquires pulse pressure variation waveform and multi-dimensional physiological data of each stroke volume; a volume benefit analysis channel of the dynamic decision-making unit segments a respiratory cycle, extracts pulse pressure fluctuation characteristics, outputs a per-stroke volume increase probability value through a machine learning classifier, an organ injury early warning channel calculates a blood lactic acid and creatinine clearance rate change rate, and generates an acute kidney injury risk sign in combination with inferior vena cava image verification; the execution control unit sends an infusion control or limit instruction according to the combined state; and the feedback optimization unit adjusts the weight of the model according to the actual value of blood lactic acid removal, and recalculates the probability value, so that individualized precise resuscitation, balance capacity benefit and organ protection are realized, and the treatment safety and effectiveness are improved.

The invention relates to the technical field of medical care, in particular to a cardiovascular disease risk dynamic early warning system based on multi-source data fusion, and the system comprises the steps: obtaining ejection fraction, coronary artery stenosis percentage and calcification integral data of cardiovascular examination of a monitored object, and heart rate data and pulse pressure difference data of periodic signs; determining a physical examination abnormal coefficient according to the difference between the ejection fraction and the standard value and the difference between the calcification integral data and the standard value and the coronary artery stenosis percentage; according to the height and slope difference of the ST wave band and the PR wave band, the heart rate analysis abnormal index is determined by combining the time interval of the adjacent electric activity wave bands; according to the time sequence change correlation of the heart rate data and the pulse pressure difference data, a physical sign abnormal coefficient is determined; determining a dynamic risk score in combination with the physical examination abnormal coefficient and the physical sign abnormal coefficient; and carrying out risk early warning based on the dynamic risk score. According to the invention, fusion analysis of multi-source and multi-dimensional data can be realized, and the dynamic early warning precision of cardiovascular risks is improved.

The invention belongs to a non-invasive blood pressure measurement method, and provides a blood pressure measurement method based on forearm local pulse transit time and a related device aiming at the technical problems that an existing blood pressure measurement method based on the forearm local pulse transit time is weak in relevancy and prone to being affected by complex factors. Non-invasive blood pressure measurement is realized by using an artificial neural network, and by synchronously detecting two paths of front arm local photoelectric volume pulse wave signals, front arm local pulse conduction time which is not highly related to blood pressure is taken as a core; in combination with demographic features having high correlation to blood pressure and other hemodynamic features except local pulse transit time, including time domain features, frequency domain features, time domain statistical features and frequency domain statistical features, sending the features to the trained prediction network model for prediction to obtain a model including systolic pressure, diastolic pressure, blood pressure, blood pressure, blood pressure, blood pressure, blood pressure, blood pressure, blood pressure and the like. And real-time blood pressure data of pulse pressure difference and average pressure.

The application discloses a blood pressure monitoring device based on multi-source physiological parameter adaptive control, comprising a blood pressure measurement module, an electrocardiogram measurement module and a processing module. The blood pressure measurement module comprises a microcontroller unit and an air pump and a deflation valve controlled thereby. The processing module acquires multi-source physiological parameters and controls the air path accordingly: when the skin conductance response is high, the deflation time is shortened to reduce the stress stimulus of the patient; when the pulse pressure difference of the initial measurement is large, the deflation frequency is increased to adapt to the rapid change of blood pressure and avoid false hypotension; when the electrocardiogram QT interval is long, the inflation time is prolonged to ensure measurement accuracy. The application dynamically adjusts the inflation and deflation physical process through multi-source physiological feedback, significantly improving the measurement accuracy and adaptability of the device under complex physiological conditions.

The application discloses a blood pressure measurement method, device, equipment, storage medium and computer program, and belongs to the technical field of intelligent terminals. The method comprises the following steps: determining posture change data and pulse pressure data of a user in a current posture; determining a height difference between a blood pressure measurement device and a heart of the user in the current posture based on the posture change data; and determining blood pressure of the user based on the pulse pressure data and the height difference between the blood pressure measurement device and the heart of the user in the current posture. According to the application, the height difference between the blood pressure measurement device and the heart of the user in the current posture is determined based on the posture change data, so that the posture of the user when measuring blood pressure does not need to be limited, and the blood pressure values measured by the user in any posture can be effectively ensured to be accurate, thereby greatly simplifying the operation steps of the user for measuring blood pressure and bringing convenience to the user.

This invention provides the use of β-1,3 / α-1,3-glucan in the preparation of functional foods that help maintain healthy blood pressure levels, belonging to the field of health foods. This invention provides a food-grade β-1,3 / α-1,3-glucan, which has been shown to significantly reduce systolic blood pressure, diastolic blood pressure, and pulse pressure, exhibiting high safety and broad applicability, providing a reliable solution for comprehensive blood pressure management.

The application provides a low-permeability rock layer pulse type hydraulic fracturing device and a pulse fracturing method, relates to the technical field of fracturing devices, and discloses the following technical scheme: a fracturing rod is provided with a front end blocking air bag and a rear end blocking air bag at the front end and the rear end of the fracturing rod, respectively; a pair of auxiliary fracturing air bag sliding sleeves are further arranged on the rod body between the front end blocking air bag and the rear end blocking air bag; the fracturing hole comprises a front section fracturing hole, a middle section fracturing hole and a rear section fracturing hole; the displacement generated by the auxiliary fracturing air bag sliding sleeves is used for positioning the fracturing position; and the front section fracturing hole, the middle section fracturing hole and the rear section fracturing hole are used for partition fracturing. The power transmission is more efficient, so that the propelling rod no longer bears huge propelling pressure, and the risk of damage is reduced; low-amplitude pulse pressure and high-amplitude pulse fracturing are used for fracturing according to the rock fracture opening and the distribution range, a low-permeability rock layer pulse fracturing method is formed, accurate and efficient fracturing of the low-permeability rock layer is realized, and more uniform fracturing effect is ensured.

The application discloses a traditional Chinese medicine blood pressure pulse condition detection system, which is used for realizing more accurate pulse condition detection, identification and classification of traditional Chinese medicine blood pressure pulse conditions of a target according to arterial blood pressure information of the target. The blood pressure pulse condition detection system provided by the application embodiment realizes that the average pressure of arterial blood pressure of the target is used as a basis for classifying pulse condition sinking and floating properties, that a pulse pressure difference is used as a basis for classifying pulse condition empty and full properties, that a pulse amplitude change law (pulse amplitude law) in a sleeve belt deflation process is used as a supplement and development for confirming pulse condition sinking and floating properties and pulse type classification, and that identification of pulse waveforms, pulse wave rhythm and rate in the sleeve belt deflation process is used as a summary for determining pulse type identification and classification, so that the traditional Chinese medicine blood pressure pulse conditions are more objectively detected and classified.

The invention belongs to the technical field of protection, and particularly relates to a method and device for evaluating the damage degree of a functional gradient multilayer metal plate under a near-field explosion load. The method specifically comprises the following steps: determining the pulse pressure generated by explosion according to the spatial distribution characteristic of the peak value of the pulse pressure on a loaded surface and the attenuation change rule of the pulse pressure along with time; calculating the plastic work of the first layer of metal according to the plastic strain component expression of the first layer of metal and the incompressibility principle; according to the plastic work of the first layer of metal, the total kinetic energy of the multiple layers of metal plates and virtual work of pulse pressure generated by explosion on virtual displacement, a control differential equation of transverse displacement of the multiple layers of metal plates is obtained; solving the differential equation to obtain the maximum lateral displacement of the multilayer board, calculating the average strain rate according to the maximum lateral displacement, and updating the flow stress; the differential equation is solved again through the flow stress obtained through updating till the set condition is met, and the currently obtained maximum transverse displacement of the multi-layer board serves as the damage degree.

The present application relates to the technical field of medical monitoring, in particular to an intelligent multi-parameter risk early warning system for critical patients. The system transforms ventricular electrical amplitude sequence and pulse pressure difference sequence in a preset sliding data window to determine relative electrical amplitude sequence and relative pulse pressure sequence. The pulse pressure variability is determined based on the pulse pressure difference sequence in the window. The reference conduction time is determined according to the electrical-mechanical delay sequence in the window. The matching cost matrix is constructed according to the reference conduction time, the relative electrical amplitude sequence and the relative pulse pressure sequence, and the optimal matching relationship is solved. The excitation-response data pair set is constructed according to the optimal matching relationship, and the waveform difference index is determined. The response reverse sequence ratio is determined according to the set. The pulse pressure variability, the waveform difference index and the response reverse sequence ratio are used for hierarchical screening to determine the physiological state and output the corresponding risk warning, thereby significantly improving the early cardiovascular abnormality recognition ability.

The invention discloses an anti-blocking traditional Chinese medicine atomization device, and relates to the technical field of atomization devices. The device comprises a shell and a nozzle, one side of the shell is fixedly connected with a fixing seat, the lower portion of the fixing seat is fixedly connected with a handle, the upper side of the fixing seat is provided with a liquid medicine bin, and an atomization pipeline connected with the liquid medicine bin is arranged in the shell; an annular pulse dredging pipe, a magnetic control channel and a magnetic control motor which are connected with the atomization pipeline are arranged in the shell. By arranging the dredging system and the intelligent control system in the shell, when the atomization pipeline is blocked, the intelligent control system can quickly sense the blockage condition and immediately start the dredging system, and the dredging system can apply pulse pressure into the atomization pipeline through the annular pulse dredging pipe, so that the atomization pipeline is dredged; impact force of the pulse is utilized to attempt to remove blockages.

The invention relates to the technical field of functional seat cushions, in particular to a crissum massage seat cushion and an auxiliary massage method thereof.The crissum massage seat cushion comprises a bottom cushion, and a miniature physiotherapy node is arranged on the middle rear portion of the bottom cushion; each miniature physiotherapy node comprises a high-resilience flexible massage bump and massage microparticles; massage microparticles are distributed on the surfaces of the massage bumps and are radially distributed on the surfaces of the massage bumps from top to bottom. According to the application, the body weight of the user is used as a unique power source, the body weight potential energy of the user is converted into mechanical kinetic energy, the mechanical kinetic energy is used as pulse pressure to be applied to the crissum area of the user through the massage bumps and the massage microparticles, and surrounding pressing stimulation is generated on the crissum area; the purposes of promoting local blood circulation, exercising the sphincter function and assisting in perianal cleaning are achieved, meanwhile, due to the integrally-formed concealment design, it is guaranteed that a user can sit at any time in daily work and life, and privacy and convenience are higher.

The invention provides a film type pressure sensor for monitoring cun-guan-chi pulses in traditional Chinese medicine pulse feeling and a preparation method thereof, and relates to the technical field of traditional Chinese medicine. The patterned silver electrode can directly correspond to three pulse areas of cun, guan and chi, independent acquisition of signals of the three parts is realized, and signal confusion caused by the fact that a traditional sensor cannot be partitioned is avoided; the patterned gasket layer can provide stable support for the piezoresistive layer, ensure accurate and reliable contact between the piezoresistive layer and the three electrode areas, and reduce interlayer interference. The multi-layer structure works cooperatively, the bottom-layer base material and the top-layer base material are guaranteed to be flexibly attached to the wrist, electric signals can be accurately output through the silver electrodes according to resistance changes of the piezoresistive layer after the piezoresistive layer is pressed, accurate monitoring of cun-guan-chi pulse pressure is achieved, and reliable support is provided for objectification of traditional Chinese medicine pulse diagnosis.

This application discloses a testing system and method for artificial heart valve implants, relating to the field of medical device testing technology. The system includes: a ventricular simulator, an atrial simulator, a highly transparent and compliant valve testing chamber containing an artificial heart valve, a vascular compliance simulator, and a vascular damping simulator forming a circulation loop, a high-speed camera, and a laser generator. The circulation loop simulates the blood flow environment of the artificial heart valve, with a tracer particle suspension added to the flow medium. The ventricular simulator, atrial simulator, vascular damper, and vascular compliance simulator provide power, storage space, resistance, and pulse pressure to the flow medium, respectively. The laser generator and high-speed camera work together to acquire particle images after implantation of the artificial heart valve. The particle images are uploaded to a computer for visual analysis of the heart valve pulsating flow field based on digital particle image velocimetry technology, thereby enabling quantitative analysis of the risk after implantation at the intended site.

The present invention relates to a device, system and method for determining pulse pressure variation of a subject. To enable more reliably determining pulse pressure variation of a subject the device comprises a signal input (11) configured to obtain an input signal representing a hemodynamic signal of the subject, a processor (12) configured to process the input signal and compute a pulse pressure variation and a signal output (13) configured to output the computed pulse pressure variation. The pulse pressure variation is computed by deriving a pulse height signal from the input signal, deriving a pulse height baseline and a de-trended pulse height signal from the pulse height signal as the ratio between the difference between extrema of the de-trended pulse height signal and the respective value of the pulse height baseline signal, and computing the pulse pressure variation from the de-trended pulse height signal and the pulse height baseline.

A pulse diagnosis device and pulse pattern recognition method are disclosed. The pulse diagnosis device includes: a wearable body for wearing on the wrist to be tested; the wearable body is provided with a pressure sensing mechanism and an ultrasound detection mechanism; wherein the ultrasound detection mechanism is used to locate at least three target pulse points on the wrist to be tested; the pressure sensing mechanism is used to apply gradient pressure to the at least three target pulse points on the wrist to be tested and to collect the pulse pressure signals of the at least three target pulse points under the action of the gradient pressure; the ultrasound detection mechanism is also used to collect vascular feature information corresponding to each of the at least three target pulse points. The technical solution of this application can effectively improve the accuracy of the pulse diagnosis device.

An example method includes outputting, toward a blood vessel of a subject during a cardiac cycle of the subject, an ultrasound signal; detecting, from the blood vessel of the subject during the cardiac cycle of the subject, a reflection of the ultrasound signal; and determining a normalized distension of the blood vessel of the subject during the cardiac cycle by analyzing the reflection of the ultrasound signal. The example method further includes determining a blood pressure of the subject by adding a mean arterial pressure of the subject to a product of the normalized distension of the blood vessel and a pulse pressure of the subject. In addition, the example method includes outputting an indication of the blood pressure.

This invention relates to the field of materials analysis and testing technology, particularly to the field of IPC G01N3 / 08, and more specifically, to a method for testing the fatigue life of static seals under high pressure and low temperature conditions. The method includes the following steps: Step 1: Performing pressure relief tests on the seal under different temperatures and pressures; Step 2: Performing a variable temperature pressure resistance test; Step 3: Replacing the seal and performing a first heating pulse pressure resistance test; Step 4: Performing a cooling pulse pressure resistance test; Step 5: Performing a second heating pulse pressure resistance test; Step 6: Performing a low-temperature pulse pressure resistance test; Step 7: Measuring the low-temperature performance of the seal before and after the experiment; Steps 1 to 6 all include continuous monitoring of pressure relief, simultaneously monitoring the ambient temperature and the actual temperature of the pulsed liquid. If pressure relief occurs at any step during the monitoring period, the test ends, and no further steps are performed. This method can evaluate the fatigue life of seals under low-temperature conditions, thereby meeting the reliability requirements of large-scale equipment.

This invention relates to the field of animal feed processing technology, and discloses a biological anionic salt preparation and its preparation method, comprising: mixing a lignocellulose carrier with anionic salt particles; heating the mixture to plasticize the fiber skeleton and maintain the bound water in the tracheid lumen in a state of accumulation; applying pulse pressure with a specific pressurization rate, using the transient volume expansion of the bound water to drive radial strain at the tracheid lumen inlet; pressing the anionic salt particles into the tracheid lumen under the pressure peak; removing the pressure and cooling, using the solubility temperature change difference to accumulate and precipitate a crystal sealing layer at the tracheid lumen inlet. This invention utilizes the kinetic response of endogenous water in the carrier to open the natural pore inlet, achieving physical integration of anionic salts, resolving the contradiction between high drug loading and storage stability, and effectively enhancing the physical masking effect and moisture resistance of the preparation.

The invention discloses a radial artery puncture catheterization teaching model. The model comprises a simulation arm body; the liquid circulation system is arranged in the simulation arm body and used for accurately adjusting the pressure waveform of output liquid so as to simulate different heart rates, heart rhythms and pulse pressures; the setting positions of the at least one group of simulated blood vessel modules correspond to the radial artery position on the simulated arm body; the simulated blood vessel module is in fluid communication with the liquid circulation system; the simulation blood vessel module comprises four types; the blood vessel simulation module is detachably connected with the liquid circulation system through the quick connection interface, so that quick replacement of the blood vessel simulation module is realized; the group of simulated arm cover plates comprises a non-transparent simulated skin cover plate and a transparent simulated skin cover plate and is used for covering the outer side of the corresponding area of the simulated blood vessel module; and the control panel is used for setting, adjusting and displaying heart rate, heart rhythm and pulse pressure parameters and recommending a matched physiological parameter mode according to the type of the selected simulation blood vessel module.

A positive displacement pump that triggers with the beating of a mammalian heart, through the monitoring of an ECG signal is disclosed. A programmable delay from the detection of the forthcoming contraction of the heart enables the pump to syncopate the ejection of the fluid with the events occurring in the cardiovascular system. This delayed ejection could be used to overlay the ejected fluid from the pump with a pressure wave in the artery of systemic circulation through a catheter connection between the pump and a physiological model (e.g., cow, dog, human). The outcome of this use could be to raise the pulse pressure in the system to take advantage of physiological pathways that respond to this transient change in blood pressure. The novelty of this system stems from the adaptable control architecture designed to augment the pulsatile characteristics of the cardiovascular system. This inventive concept could be expanded to encompass the augmentation (dampen or enhance) of pulsatile characteristics in any oscillating flow system.

The invention discloses an electric hemostatic instrument control method and system, and belongs to the technical field of biomedical engineering. According to the method, a multi-level intelligent control framework is formed by constructing an equipment compression state model, a dynamic process model, an environment state model, a basic limb occlusion pressure model and a target compression force model. The method comprises the following steps: firstly, evaluating an equipment matching state based on cuff width, equipment response speed and personnel limb conicity, optimizing process control by combining initial compression force, pressurization speed and compression duration, and judging system reliability according to environment temperature and vibration amplitude; the coefficients, the real-time pulse pressure and the oxyhemoglobin saturation are fused, and the basic limb occlusion pressure is calculated through a two-way adjusting mechanism; and finally, in combination with the dynamic process coefficient and the basic pulse pressure, target compression force is output through smooth amplitude limiting processing. The multi-parameter self-adaptive precise regulation and control of the compression force are realized, and the rapid hemostasis and the tissue safety protection are effectively considered.

The invention discloses a radial artery hemostasis compression device based on PID (Proportion Integration Differentiation) adjustment, which comprises a compression air bag and a wrist strap structure for binding the compression air bag on a wrist, and is characterized by further comprising a pressure sensor attached to a radial artery, a balance air hole is formed in the compression air bag, and the compression air bag is connected with a precise air channel through the balance air hole. The pneumatic mechanism is communicated with the compression air bag through a precise air passage and a balance air hole; an air pressure sensor for monitoring the pressure of the compression air bag is also arranged in the compression air bag; and the control module is used for controlling the pneumatic mechanism to operate. According to the invention, through a PID adjustment mode, the pressure change in the compression air bag can better accord with the pressure change curve of the radial artery. And the compression force of the compression air bag on the puncture position of the radial artery is slightly higher than the real-time pulse pressure of the radial artery. While hemostasis is ensured, weak blood flow of the radial artery can be maintained as much as possible. A breathing space is provided for the vascular wall, and endothelial injury caused by long-time mechanical compression is prevented.

This invention relates to the field of medical monitoring technology, specifically to an intelligent multi-parameter risk early warning system for critically ill patients. The system transforms ventricular amplitude and pulse pressure sequences within a preset sliding data window to determine relative amplitude and relative pulse pressure sequences; it then determines pulse pressure variability based on the pulse pressure difference sequence within the window; it determines a reference conduction time based on the electromechanical delay sequence within the window; it constructs a matching cost matrix based on the reference conduction time, relative amplitude, and relative pulse pressure sequences, and solves for the optimal matching relationship; it constructs an excitation-response data pair set based on the optimal matching relationship and determines a waveform difference index; it determines the response inversion ratio based on the set; and it performs graded screening based on pulse pressure variability, waveform difference index, and response inversion ratio to determine physiological status and output corresponding risk warnings, thereby significantly improving the ability to identify early cardiovascular abnormalities.

The application discloses a biological material disinfection method, system and equipment based on big data analysis, and relates to the technical field of disinfection. The method comprises the following steps: determining a target disinfectant; performing Micro-CT scanning on the biological material to construct a 3D digital model; reading physical attribute information of the target disinfectant and an interaction relationship between the target disinfectant and the biological material; simulating the space-time dynamic distribution of the flow, diffusion and penetration of the target disinfectant in the internal pore channel of the material on the basis of the 3D digital model; optimizing the flow field and concentration field of the internal disinfection blind area through pulse pressure circulation; and generating target disinfection parameters to control the disinfection of the biological material. The technical problems that the adaptability of the disinfectant and the biological material is insufficient in the prior art, resulting in incomplete disinfection and material structure damage are solved, the adaptability between the disinfectant and the biological material is achieved, the internal pore channel of the material is fully disinfected, and the technical effect of effectively reducing the material damage risk is realized.

This invention relates to an electromagnetically controlled pulse air pressure generating device, comprising a buffer airbag for buffering gas. The buffer airbag includes an air exchange interface for connecting to a main air pump and a gas receiving device, respectively. An electromagnet is provided at either the upper or lower end of the buffer airbag, and a magnetizable object is provided at the end corresponding to the electromagnet. The electromagnet and the magnetizable object are fixedly connected to the buffer airbag. This invention uses electromagnets and magnetizable objects on both sides of the buffer airbag in different directions. By energizing the electromagnets to generate magnetic force, the internal pressure of the buffer airbag is controlled, and the pressure is periodically changed to generate pulse pressure. When connected to the air circuit of an existing pneumatic massage system, the pulse air pressure is superimposed in the air circuit. Using a PWM signal, the timing of energizing and de-energizing the electromagnets is controlled to achieve different pulse frequencies, acting on the gas receiving device in contact with the human body to produce an effect similar to mechanical vibration.

The disclosed concepts are directed to providing protocols, ideas, concepts, designs, methods and systems related to determining vascular compliance of a subject. In particular, blood pressure and arterial flow of first and second arteries (corresponding arteries on the same or contralateral limb) are measured (e.g., as a function of arterial diameter and / or velocity at which blood travels through the arteries). The pulse pressure can be determined from the blood pressure and the pulse quantity can be determined from the arterial flow. Vascular compliance can be determined from the pulse pressure and the volumetric pressure. Therefore, a direct and accurate vascular compliance estimation result can be obtained in a non-invasive manner. Also disclosed is using the determined vascular compliance in a transfer function to obtain accurate hemodynamic parameter estimates (e.g., cardiac output and stroke output) of a subject.

A system (100) for determining a fluid responsiveness parameter, FRP, for a patient is presented, wherein the determined fluid responsiveness parameter is a systolic pressure variation (SPV) or a pulse pressure variation (PPV) that comprises units (101, 102, 103) for providing a respiratory rate, a heart rate and a measured blood pulsation signal indicative of a series of blood pulses of a patient. The system further comprises a unit (104) for determining, a first processed signal (env_up) based on the blood pulsation signal, wherein the first processed signal is indicative of an upper envelope of the blood pulsation signal, and a second processed signal (env_down) based on the blood pulsation signal, wherein the second processed signal is indicative of a lower envelope of the blood pulsation signal, and a unit (105) for determining the FRP by a) identifying, based on the first and second processed signals, first FRP determination signals (baseline_up, baseline_down) corresponding to the first and second processed signals in a spectral range up to the respiratory rate, and second FRP determination signals (ripple_up, ripple_down) corresponding to the first and second processed signals at the respiratory rate and any of its harmonics up to the heart rate, and b) determining the FRP based on the first and the second FRP determination signals.