141 results about "Pulse Transit Time" patented technology

An apparatus and methods for performing a circulatory measurement on an extremity, such as a hand, of a subject. The circulatory measurement results in the derivation of an output circulatory metric that may encompass blood pressure or various other circulatory metrics. An indicator of an input circulatory metric at a locus on the extremity is measured, such as a pulse transit time. To determine the pulse transit time, a first plethysmographic signal may be obtained at a first position on the extremity, while a second plethysmographic signal may be obtained at a second position on the extremity of the subject. A transit time characterizing a circulatory pressure wave is calculated based on the first and second plethysmographic signals, leading to derivation of a wave speed. A calibration is then applied to provide the circulatory measurement based at least on the derived wave speed and a measured indicator of a hydrostatic component of blood pressure. Calibration is provided, in certain described embodiments, by derivation of two calibration parameters, a gain and a pulse transit time at zero pressure. Methods for deriving the calibration parameters include performing measurements under distinct hydrostatic pressure conditions, and based upon a measured derivative with respect to pressure of the pulse wave velocity.

The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed. A processing component, typically worn on the patient's body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed. A processing component, typically worn on the patient's body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

A method and apparatus for continuous measurement of blood pressure, based on pulse transit time, which does not require any external calibration. This technique, referred to herein as the ‘composite technique’, is carried out with a body-won sensor that measures blood pressure and other vital signs, and wirelessly transmits them to a remote monitor. A network of disposable sensors, typically placed on the patient's right arm and chest, connect to the body sensor and measure a time-dependent electrical waveform, optical waveform, and pressure waveform. The disposable sensors typically include an armband that features an inflatable bladder coupled to a pressure sensor, at least 3 electrical sensors (e.g. electrodes), and an optical sensor (e.g., a light source and photodiode) attached to a wrist-worn band.

The present invention provides a technique for continuous measurement of blood pressure based on pulse transit time and which does not require any external calibration. This technique, referred to herein as the ‘Composite Method’, is carried out with a body-worn monitor that measures blood pressure and other vital signs, and wirelessly transmits them to a remote monitor. A network of body-worn sensors, typically placed on the patient's right arm and chest, connect to the body-worn monitor and measure time-dependent ECG, PPG, accelerometer, and pressure waveforms. The disposable sensors can include a cuff that features an inflatable bladder coupled to a pressure sensor, three or more electrical sensors (e.g. electrodes), three or more accelerometers, a temperature sensor, and an optical sensor (e.g., a light source and photodiode) attached to the patient's thumb.

The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed. A processing component, typically worn on the patient's body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

An apparatus and methods for adaptive and autonomous calibration of pulse transit time measurements to obtain arterial blood pressure using arterial pressure variation. The apparatus and methods give pulse transit time (PTT) devices an ability to self-calibrate. The methods apply a distributed model with lumped parameters, and may be implemented, for example, using pulse transit time measurements derived from a wearable photoplethysmograph (PPG) sensor architecture with an intervening pressurizing mechanism.

Ambulatory monitoring of human health is provided by a multi-component multi-sensor wireless wearable biosignal acquisition system comprising a torso device and a peripheral device communicating wirelessly, and a mobile phone for receiving collected data and uploading it over cellular network or WiFi to a remote computer for multivariate analysis. Biosignals include EKG and PPG, from which a determination of pulse transit time can be made.

The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed. A processing component, typically worn on the patient's body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

A biosignal measurement module is provided and includes a biosignal measurement unit, a pose detection unit, and a processing unit. The biosignal measurement unit measures an electrocardiogram signal and a pulse signal of a subject. The pose detection unit detects a position of the biosignal measurement module and outputs position signals. The processing unit receives the electrocardiogram signal, the pulse signal, and the position signals. The processing unit generates a height variation parameter, which indicates the height difference between the position of the biosignal measurement module and a reference position, according to the position signals. The processing unit calculates a current pulse transit time according to the electrocardiogram signal and the pulse signal and compensates for the current pulse transit time according to the height variation parameter to obtain a compensated pulse transit time. The processing unit obtains a blood pressure signal according to the compensated pulse transit time.

The invention provides a system and method for measuring vital signs (e.g. SYS, DIA, SpO2, heart rate, and respiratory rate) and motion (e.g. activity level, posture, degree of motion, and arm height) from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed. A processing component, typically worn on the patient's body and featuring a microprocessor, receives the time-dependent waveforms generated by the different sensors and processes them to determine: (i) a pulse transit time calculated using a time difference between features in two separate time-dependent waveforms, (ii) a blood pressure value calculated from the time difference, and (iii) a motion parameter calculated from at least one motion waveform.

The invention relates to a method for distance measurement by determining the pulse transit time, in which pulsed electromagnetic radiation is transmitted using at least one transmitter and signal pulses reflected at objects are detected using at least one receiver, wherein at least one received logic signal containing logic signals is generated from the received analog signal containing the signal pulses, in particular by means of a threshold circuit, and is evaluated with respect to the transit times of the logic signals, and wherein the received logic signal is read into a programmable logic circuit by means of a clocked data reading device and is mapped onto a time pattern in the logic circuit, in that instantaneous values of the received logic signal are stored in logic units of the logic circuit associated with the time windows for time windows of the time pattern corresponding to at least one clock pulse of the data reading device. The invention moreover relates to an apparatus for distance measurement.

Wrist-worn devices and related methods measure a pulse transit time non-invasively and calculate a blood pressure value using the pulse transit time. A wrist-worn device includes an accelerometer, a photo-plethysmogram (PPG) or a pulse pressure sensor, and a controller. The PPG or the pulse pressure sensor coupled to the wrist-worn device for detecting an arrival of a blood pressure pulse at the user's wrist. The controller is configured to process output signals from the accelerometer to detect when the blood pressure pulse is propagated from the left ventricle of the user's heart, process a signal from the PPG or the pulse pressure sensor to detect when the blood pressure pulse arrives at the wrist, calculate a pulse transit time (PTT) for propagation of the blood pressure pulse from the left ventricle to the wrist, and generate one or more blood pressure values for the user based on the PTT.

A touch sensor panel can be constructed on a single surface of a substrate. The panel can be formed as a plurality of distributed RC lines arranged in an array of rows and columns. Each distributed RC line can include alternating connected transistors and metal pads formed on a single surface of the substrate. During operation, the rows and columns are enabled at different times, and the pulse travel times for each row and column in both directions are measured. Equalized travel times are then computed as the sum of the pulse travel times in both directions, and indicate which rows and columns have a finger touching it. The un-equalized pulse travel time data can then be used to determine the relative positions of the fingers within the rows and columns and un-ambiguously determine the positions of all the finger contacts.

Wrist-worn devices and related methods measure a pulse transit time non-invasively and calculate a blood pressure value using the pulse transit time. A wrist-worn device include a wrist-worn elongate band, at least four EKG or ICG electrodes coupled to the wrist-worn device for detecting a ventricular ejection of a heart, a photo-plethysmogram (PPG) sensor coupled to the wrist-worn device for detecting arrival of a blood pressure pulse at the user's wrist, and a controller configured to calculate a pulse transit time (PTT) for the blood pressure pulse. The controller calculates one or more blood pressure values for the user based on the PTT.

An image-based PWV measurement device and method are provided. The measurement device comprises at least two light emitting units respectively projecting light beams to at least two detected regions on body surface; at least two light transmitting units respectively receiving and transmitting light signals measured at the different detected regions; an image sensing unit converting the light signals measured at the detected regions into image signals; a length measurement unit used to measure the distance between the detected regions; and an image analysis unit analyzing the image signals to obtain PPG signals for the detected regions. According to the PPG signals, the image analysis unit calculates the physiological parameters, including the perfusion index, respiration rate, pulse rate, stiffness index, reflection index, and PWV between the detected regions, which is derived according to the distance and the pulse transit time from the PPG signals of the two detected regions.

Apparatus, method, and software for electrocardiogram-assisted non-invasive arterial blood pressure d stiffness measurement is disclosed including brachial cuff with flexible electrodes, control box with rigid electrodes, and associated hardware/software. Cuff is wrapped around upper arm while electrodes on device are touched with fingers of other hand. Device acquires simultaneous ECG/oscillometric data during cuff deflation. Processing unit determines ECG R-peak positions to isolate arterial pulses and calculate pulse transit time. Change in pulse amplitude as function of cuff pressure is used for constructing oscillometric envelope and calculating blood pressure using empirical coefficients. Change in pulse transit time as function of cuff pressure is used independently for constructing pulse transit time envelopes and finding blood pressure with/without empirical coefficients. Fusion algorithm combines results for robust blood pressure and vessel stiffness evaluation. Device sends physiological information to personal computer/smartphone wirelessly, for further analysis. Computer/smartphone transmits information to third party for patient management.

The present invention relates to a device and method for obtaining pulse transit time and/or pulse wave velocity information of a subject (14). Based on a set of image frames (19) of a subject (14) and detected motion of body parts of the subject (14) regions of interest are selected from different non-moving body parts and pulse transit time and/or pulse wave velocity information is obtained from acquired PPG signals extracted from different regions of interest and the respective determined physical distance between the respective regions of interest.