Abstract: Devices and methods for multi-parameter hemodynamic monitoring are provided. Determining a cardiac output of a patient using a cuff device includes measuring a cuff pressure waveform of a subject during inflation and/or deflation of the cuff device, computing systolic and diastolic blood pressure from the cuff pressure waveform using the cuff device, constructing a blood pressure waveform from the systolic and diastolic blood pressure and cuff pressure waveform using the cuff device, computing brachial artery compliance from the cuff pressure waveform, and computing the cardiac output from the blood pressure waveform and/or brachial artery compliance using the cuff device.

Abstract: Current oscillometric devices for monitoring central blood pressure (BP) maintain the cuff pressure at a constant level to acquire a pulse volume plethysmography (PVP) waveform and calibrate it to brachial BP levels estimated with population average methods. A physiologic method was developed to further advance central BP measurement. A patient-specific method was applied to estimate brachial BP levels from a cuff pressure waveform obtained during conventional deflation via a nonlinear arterial compliance model. A physiologically-inspired method was then employed to extract the PVP waveform from the same waveform via ensemble averaging and calibrate it to the brachial BP levels. A method based on a wave reflection model was thereafter employed to define a variable transfer function, which was applied to the calibrated waveform to derive central BP.

Abstract: An aortic aneurysm carries increasing risk of rupture with growing aneurysm diameter. This condition is typically asymptomatic, so screening and surveillance are essential. Ultrasound and other imaging methods are employed for such monitoring at high accuracy. However, these methods require an expert and are expensive. Aortic aneurysms are considerably under-detected at present and may become even more under-detected in the future as the disease prevalence increases with societal aging. This disclosure present devices that are convenient in use and cost for aortic aneurysm screening and surveillance.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: A method and apparatus for monitoring arterial properties, including systolic and diastolic pressure levels, of a subject is provided, in which a hardware processor receives and analyzes ballistocardiogram (BCG) data of the subject. A non-transient computer readable medium, accessible by the hardware processor, contains instructions that, when executed by the hardware processor, identify features of the BCG waveform and determine the arterial properties therefrom. For example, a diastolic pressure level may be determined from a time interval between the ‘I’ and ‘J’ peaks of the waveform and a systolic pressure level determined from the amplitude difference between the ‘J’ and ‘K’ peaks of the waveform in combination with the ‘I-J’ time interval or amplitude difference. A physical mechanism for the BCG data is disclosed that enables other arterial properties of the subject to be determined from the BCG data alone or from the BCG data in combination with other measurements.

Abstract: An apparatus for generating a blood pressure estimation model includes: a signal acquirer configured to receive input a first signal and a second signal from a user; and a processor configured to obtain a pulse transit time (PTT) as a first predictor variable value based on the first signal and the second signal, to extract at least one feature from the second signal, to obtain a second predictor variable value based on the extracted at least one feature, and to generate a blood pressure estimation model based on the first predictor variable value and the second predictor variable value.

Abstract: Most automatic cuff blood pressure (BP) measurement devices are based on oscillometry. These devices estimate BP from the envelopes of the cuff pressure oscillations using fixed ratios. The values of the fixed ratios represent population averages, so the devices may be accurate only in subjects with normal BP levels. A patient-specific oscillometric BP measurement method was developed. The idea was to represent the cuff pressure oscillation envelopes with a physiologic model and then estimate the patient-specific parameters of the model, which includes BP levels, by optimally fitting it to the envelopes.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: Systems and methods for gas exchange in a patient are provided that use an external circuit to cause oxygenation perfusion in a patient's body cavity (such as the abdomen) using an inert chemical (e.g., perfluorocarbon), independent of the lungs. The external circuit includes components configured to control properties of the chemical, including temperature, flow rate, pressure, oxygenation percentage, carbon dioxide percentage. The system also includes safety features to reduce the likelihood of injury to the patient. Each of the safety features and chemical properties can be controlled by a healthcare worker, such as a physician, nurse, or emergency operator, for a particular patient.

Abstract: An apparatus for estimating bio-information of a user may include a first sensor configured to measure a first signal from the user; a second sensor configured to measure a second signal from the user; and a processor configured to obtain a first characteristic point from the first signal; obtain a second characteristic point from the second signal based on the first characteristic point and a pre-defined probability distribution function; and estimate the bio-information of the user based on the second characteristic point.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: Aspects of the disclosure relate to estimation of cardiovascular parameters based on a ballistocardiogram signal. In one example, an apparatus for estimating cardiovascular parameters includes a BCG sensor for producing a BCG signal of a user, a processor, a display, and a memory communicatively coupled to the processor. The processor and the memory are configured to transform the BCG signal to a synthetic whole-body BCG signal by integrating the BCG signal in time twice and zero-phase filtering the BCG signal, estimate the cardiovascular parameters based on the synthetic whole-body BCG signal, and display the cardiovascular parameters to the display. Other aspects, embodiments, and features are also claimed and described.

Abstract: Current oscillometric devices for monitoring central blood pressure (BP) maintain the cuff pressure at a constant level to acquire a pulse volume plethysmography (PVP) waveform and calibrate it to brachial BP levels estimated with population average methods. A physiologic method was developed to further advance central BP measurement. A patient-specific method was applied to estimate brachial BP levels from a cuff pressure waveform obtained during conventional deflation via a nonlinear arterial compliance model. A physiologically-inspired method was then employed to extract the PVP waveform from the same waveform via ensemble averaging and calibrate it to the brachial BP levels. A method based on a wave reflection model was thereafter employed to define a variable transfer function, which was applied to the calibrated waveform to derive central BP.

Abstract: Systems and methods for monitoring and/or controlling a state of a subject during volume resuscitation are disclosed. One method includes acquiring cardiovascular data from a subject, obtaining previous volume administration information, and analyzing the cardiovascular data to determine a past time trajectory for at least one cardiovascular parameter. The method also includes determining a future state of the subject with and without additional volume administration using a statistical model, and determining, based on the future state of the subject, a likelihood that the at least one cardiovascular parameter will exceed or fall below a threshold at one or more pre-determined time points. The method further includes generating a report including a recommendation for administering an additional volume to the subject based on the determined likelihood and controlling administration of an additional fluid volume to the subject based on the report.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: A method is provided for determining blood pressure for a subject using a sphygmomanometer. The method includes: measuring an oscillometric cuff pressure waveform of the subject using the sphygmomanometer; representing the measured waveform with a physical model accounting for mechanics of the cuff, an artery and coupling between the cuff and the artery; determining the model unknowns from the measured waveform; and determining blood pressure for the subject using the determined model.

Abstract: A system and method is presented for cuff-less blood pressure measurement in a mobile device. A key aspect of this disclosure is the discovery of a new location for blood pressure measurement at the fingertip of a subject and that reflectance-mode photoplethysmography can be used to help make this measurement. Through experiments in human subjects, it was discovered that it is indeed possible to measure systemic blood pressure by having a subject press the fingertip against a reflectance-mode photo-plethysmography-force sensor unit under visual guidance and then compute blood pressure from the resulting variable-amplitude blood volume oscillations and applied pressure via an oscillometric algorithm.

Abstract: A method is provided for determining blood pressure for a subject using a sphygmomanometer. The method includes: measuring an oscillometric cuff pressure waveform of the subject using the sphygmomanometer; representing the measured waveform with a physical model accounting for mechanics of the cuff, an artery and coupling between the cuff and the artery; determining the model unknowns from the measured waveform; and determining blood pressure for the subject using the determined model.

Abstract: A method and apparatus for monitoring arterial properties, including systolic and diastolic pressure levels, of a subject is provided, in which a hardware processor receives and analyzes ballistocardiogram (BCG) data of the subject. A non-transient computer readable medium, accessible by the hardware processor, contains instructions that, when executed by the hardware processor, identify features of the BCG waveform and determine the arterial properties therefrom. For example, a diastolic pressure level may be determined from a time interval between the ‘I’ and ‘J’ peaks of the waveform and a systolic pressure level determined from the amplitude difference between the ‘J’ and ‘K’ peaks of the waveform in combination with the ‘I-J’ time interval or amplitude difference. A physical mechanism for the BCG data is disclosed that enables other arterial properties of the subject to be determined from the BCG data alone or from the BCG data in combination with other measurements.