US 2025/0375112 A1 · METHOD FOR CUFF-LESS BEAT-TO-BEAT BLOOD PRESSURE ESTIMATION USING TWO RELATIVE BLOOD VOLUME SENSORS ON DIFFERENT APPLIED PRESSURES

Abstract

The invention describes a measurement method for the continuous non-invasive determination of blood pressure using two blood volume sensors, which are under two different applied pressures. The non-linear function, which is updated for each cardiac cycle, is used to model the relationship between blood pressure and relative blood volume change. The model depends on relative blood volume changes and applied external pressures to the sensors. The derived model needs one point blood pressure calibration. The blood volume sensor can be optical sensor, such as photoplethysmographic sensor, however, any transducer, which converts blood volume or relative blood volume to electrical signal, is applicable. As one possible application, the method can be used for the blood pressure determination at one finger. However, the method is not limited with the blood volume measurement sites (e.g. radial artery etc.).

Claims15

Dependent claims

A device for continuous non-invasive monitoring of arterial blood pressure based on the dependence function of pressure and volume curves for estimating arterial blood pressure, comprising:

two optical sensors consisting of a light source and a photodetector;
digital-analogue converters attached to the light sources;
transimpedance amplifiers electrically connected to the photodetectors;
force transducers attached to the optical sensors;
analogue-to-digital converters electrically connected to the force transducers and transimpedance amplifiers;
a microcontroller electrically connected to the analogue-to-digital converters and digital-to-analogue converters;
a memory electrically connected to the microcontroller;
and
an external communication port;
wherein a sensor housing comprises recesses for one or both optocouples in order to produce differences in the back pressures exerted by the optical sensors.

7 more elements

A device for continuous non-invasive monitoring of arterial blood pressure based on the dependence function of pressure and volume curves for estimating arterial blood pressure, comprising

two optical sensors consisting of a light source and a photodetector;
digital-to-analogue converters connected to the light sources;
transimpedance amplifiers electrically connected to the photodetectors;
spring loaded force transducers attached to the optical sensors;
analogue-to-digital converters electrically connected to the force transducers and transimpedance amplifiers;
microcontrollers electrically connected to the analogue-to-digital converters and the digital-to-analogue converters;
a memory electrically connected to the microcontroller;
and
an external communication port;
wherein a first spring is mounted between the first optical sensor and the first force transducers, the stiffness of which differs 0.1 to 2 times from the stiffness of the second spring mounted between the second optical sensor and the second force transducers, in order to create differences in the back pressures expressed by the optical sensors 2).

7 more elements

Dependencies are inferred from the claim text.

Method for cuff-less beat-to-beat blood pressure estimation using two relative blood volume sensors on different applied pressures

Life of this patent

Method for cuff-less beat-to-beat blood pressure estimation using two relative blood volume sensors on different applied pressures

Life of this patent

Abstract

Claims15