Device and method for the continuous non-invasive measurement of blood pressure

• US 7,390,301 B2
• Filed: 04/01/2004
• Issued: 06/24/2008
• Est. Priority Date: 04/01/2003
• Status: Expired due to Fees

• Current Assignee: CNSystems Medizintechnik GmbH (CNSystems Medizintechnik AG)
• Original Assignee: CNSystems Medizintechnik GmbH (CNSystems Medizintechnik AG)
• Inventors: Fortin, Jürgen, Skrabal, Falko
• Primary Examiner(s): Marmor, II; Charles A.
• Assistant Examiner(s): Natnithithadha; Navin
• Application Number:
  US10/551,189
• Publication Number:
  US 20060195034A1
• Time in Patent Office: 1,545 Days
• Field of Search: 600/481, 600483-486, 600490-507, 600/488
• US Class Current: 600/490
• CPC Class Codes: A61B 5/02241 of small dimensions, e.g. adapted to fingers
• CPC Class Codes: A61B 5/02255 the pressure being controlled by plethysmographic signals, e.g. derived from optical sensors
• CPC Class Codes: A61B 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• CPC Class Codes: A61B 5/6806 Gloves

Abstract

A method for the continuous non-invasive measurement of blood pressure includes at least one first pressure cuff and one second pressure cuff of comparable or identical size, each cuff including an inflatable pressure measuring chamber applicable to a first and a second body part or region containing an artery. The first pressure cuff has a first plethysmographic sensor connected to a regulating and control device used to regulate the pressure in a first pressure measuring chamber by means of a measuring signal of the plethysmographic sensor. The first pressure measuring chamber is connected to a pressure sensor in order to obtain a pressure measuring signal. The second pressure measuring chamber is a reference pressure chamber that can be regulated at the same time as the first pressure measuring chamber, independently therefrom, and can be regulated by the regulating and control device according to a pre-determinable pressure function.

Claims

1. A method for the continuous, non-invasive measurement of blood pressure based on the principle of the unloaded arterial wall, comprising

positioning a first and a second pressure cuff of identical or comparable size with a first and a second inflatable pressure measuring chamber on at least one first and one second neighboring finger, each containing an artery of identical or comparable size,

controlling pressure in the first pressure measuring chamber in dependence on a measurement signal of a plethysmographic sensor device in such a way that an amplitude of the plethysmographic measurement signal is minimized,

obtaining a pressure measuring signal from the first pressure measurement chamber,

operating the second pressure measuring chamber as a reference pressure chamber independently of the first pressure measuring chamber,

controlling the pressure in the reference pressure chamber in dependence on a measurement signal of a second plethysmographic sensor device and in accordance with a preselectable pressure function, a reference signal being obtained simultaneously with the pressure measuring signal, and the reference signal used in the interpretation of the pressure measuring signal wherein an amplitude of said obtained reference signal is minimized while a reference pressure signal is measured, and

analyzing the reference pressure signal, measured at various pre-selectable pressure values of the pressure function, compared to predetermined ideal pulse curves, and, when the deviation from a given pulse curve is at a minimum, determining the setpoint for the pressure measuring signal therefrom.

5. Method according to claims 1, 2, 3 or 4 comprising continuously monitoring and/or adjusting a setpoint of the pressure measuring signal by means of the reference signal.

2. A method for the continuous, non-invasive measurement of blood pressure based on the principle of the unloaded arterial wall, comprising

positioning a first and a second pressure cuff of identical or comparable size with a first and a second inflatable pressure measuring chamber on at least one first and one second neighboring finger, each containing an artery of identical or comparable size,

controlling pressure in the first pressure measuring chamber in dependence on a measurement signal of a plethysmographic sensor device in such a way that an amplitude of the plethysmographic measurement signal is minimized,

obtaining a pressure measuring signal from the first pressure measurement chamber,

operating the second pressure measuring chamber as a reference pressure chamber independently of the first pressure measuring chamber,

controlling the pressure in the reference pressure chamber in dependence on a measurement signal of a second plethysmographic sensor device and in accordance with a preselectable pressure function, a reference signal being obtained simultaneously with the pressure measuring signal, and the reference signal used in the interpretation of the pressure measuring signal, and inferring a physiological or pathological change of the pressure measuring signal from a change of a mean pressure and/or amplitude of the pressure measuring signal and a shift of amplitude maximum of the reference signal or the reference pressure signal in the same direction.

3. A method for the continuous, non-invasive measurement of blood pressure based on the principle of the unloaded arterial wall, comprising

positioning a first and a second pressure cuff of identical or comparable size with a first and a second inflatable pressure measuring chamber on at least one first and one second neighboring finger, each containing an artery of identical or comparable size,

controlling pressure in the first pressure measuring chamber in dependence on a measurement signal of a plethysmographic sensor device in such a way that an amplitude of the plethysmographic measurement signal is minimized,

obtaining a pressure measuring signal from the first pressure measurement chamber,

operating the second pressure measuring chamber as a reference pressure chamber independently of the first pressure measuring chamber,

controlling the pressure in the reference pressure chamber in dependence on a measurement signal of a second plethysmographic sensor device and in accordance with a preselectable pressure function, a reference signal being obtained simultaneously with the pressure measuring signal, and the reference signal used in the interpretation of the pressure measuring signal, and

inferring a loss of setpoint of the pressure signal from a change of the mean pressure and/or the amplitude of the pressure measuring signal and an absent or oppositely directed shift of the amplitude maximum of the reference signal or the reference pressure signal.

4. A method for the continuous, non-invasive measurement of blood pressure based on the principle of the unloaded arterial wall, comprising

positioning a first and a second pressure cuff of identical or comparable size with a first and a second inflatable pressure measuring chamber on at least one first and one second neighboring finger, each containing an artery of identical or comparable size,

controlling pressure in the first pressure measuring chamber in dependence on a measurement signal of a plethysmographic sensor device in such a way that an amplitude of the plethysmographic measurement signal is minimized,

obtaining a pressure measuring signal from the first pressure measurement chamber,

operating the second pressure measuring chamber as a reference pressure chamber independently of the first pressure measuring chamber,

controlling the pressure in the reference pressure chamber in dependence on a measurement signal of a second plethysmographic sensor device and in accordance with a preselectable pressure function, a reference signal being obtained simultaneously with the pressure measuring signal, and the reference signal used in the interpretation of the pressure measuring signal, and

wherein at preselectable time intervals or triggered by loss of setpoint the reference pressure chamber is operated as pressure measuring chamber and the pressure measuring chamber as reference pressure chamber.