University System of Maryland

Michigan State University

Samsung Electronics Co., Ltd.

Georgia Tech Research Corporation

Jin-Oh Hahn

Ramakrishna Mukkamala

Anand Chandrasekhar

Ui Kun Kwon

Youn Ho Kim

Dae Geun Jang

Peyman Yousefian

Sungtae Shin

Jiankun Liu

Omer T Inan

Mohsen Moslehpour

Kevin Aroom

Keerthana Natarajan

Stephanie Lind-Ober Martin

Mahsa Doosthosseini

Majid Aroom

Chang-Sei Kim

Joseph Friedberg

Hosam Fathy

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

Peritoneal oxygenation system and method

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.

Apparatus and method for estimating bio-information

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.

Apparatus and method for generating blood pressure estimation model, and apparatus for estimating blood pressure

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.

Central blood pressure monitoring via a standard automatic arm cuff

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.

Method and apparatus for cuff-less blood pressure measurement in a mobile device

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 &#x2018;J&#x2019; and &#x2018;K&#x2019; peaks of the waveform in combination with the &#x2018;I-J&#x2019; 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.

Monitor for blood pressure and other arterial properties

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.

Method for determining cuff blood pressure

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.

Growing community of inventors

Rockville, MD, United States of America

Jin-Oh Hahn