Apparatus for the non-invasive measurement of the blood flow

Abstract

An apparatus for the non-invasive measurement of the blood flow through a shunt of a patient has at least one bandage which can be worn by the patient, as well as a plurality of sensors which are arranged in or at the bandage, which are arranged in at least one multidimensional matrix, and which are configured such that they create a multidimensional matrix of measured values of at least one parameter detected by the sensors.

Claims

1. An apparatus for non-invasive measurement of blood flow through a shunt of a patient, said apparatus comprising: a bandage configured to be worn by the patient; a plurality of skin stretching sensors arranged at the bandage, the skin stretching sensors being arranged in a multidimensional matrix, and being configured to measure values resulting from a multidimensional pattern of skin stretching that is associated with oscillating variations in blood pressure and ultimately the blood flow through the shunt; an evaluation unit configured to process the measured values including generating a spatio-temporal pattern of the spatial stretching of a surface of the skin which reproduces the measured values of the skin stretching sensors simultaneously, and comparing the measured stretching values with reference values so as to generate a pattern providing a comparison of the measured stretching values relative to the reference values, the generated pattern including white and black boxes, with each white box corresponding to a pressure value which lies below a reference value and each black box corresponding to a pressure value which lies above a reference value; a transmission unit configured to be in communication with the evaluation unit and to transmit the generated pattern therefrom; and a receiver configured to receive the generated pattern transmitted by the transmission unit so as to facilitate treatment of the patient based on the non-invasive measurement.

2. The apparatus in accordance with claim 1, wherein the matrix is a two-dimensional matrix and the pattern is a two-dimensional pattern.

3. The apparatus in accordance with claim 1, further comprising sensors for detecting a heart activity of the patient.

4. The apparatus in accordance with claim 1, wherein the measured values are absolute values.

5. The apparatus in accordance with claim 1, further comprising a memory to store the measured values.

6. The apparatus according to claim 5, Therein the memory is arranged at the bandage.

7. The apparatus according to claim 1, wherein the transmission unit is configured for wireless transmission.

8. The apparatus in accordance with claim 1, wherein the evaluation unit is arranged at the bandage.

9. The apparatus in accordance with claim 1, further comprising a Peltier element as an energy source.

10. A method of non-invasive measurement of blood flow through a shunt of a patient, said method comprising: providing an apparatus for the non-invasive measurement of the blood flow through the shunt, the apparatus including a bandage configured to be worn by the patient and having a plurality of skin stretching sensors arranged at the bandage, the skin stretching sensors being arranged in a multidimensional matrix, and being configured to measure values resulting from a multidimensional pattern of skin stretching that is associated with oscillating variations in blood pressure and ultimately the blood flow through the shunt, An evaluation unit, a transmission unit in communication with the evaluation unit, and a receiver, applying the bandage to the patient; with the evaluation unit, processing the measured values, including generating a spatio-temporal pattern of the spatial stretching of a surface of the skin which reproduces the measured values of the skin stretching sensors simultaneously, and comparing the measured stretching values with reference values so as to generate a pattern providing a comparison of the measured stretching values relative to the reference values, the generated pattern including white and black boxes, with each white box corresponding to a pressure value which lies below a reference value and each black box corresponding to a pressure value which lies above a reference value; with the transmission unit, transmitting the generated pattern therefrom; and with the receiver, receiving the generated pattern transmitted by the transmission unit so as to facilitate treatment of the patient based on the non-invasive measurement.

11. The method according to claim 10, wherein the transmitting is wireless.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages and particulars of the invention will be explained in more detail with reference to an embodiment shown in the drawing. There are shown:

(2) FIG. 1: an exemplary representation of a two-dimensional pattern of the pressures detected by means of the sensors; and

(3) FIG. 2: a perspective representation of the bandage in accordance with the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(4) Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

(5) The two-dimensional pressure pattern 100 in accordance with FIG. 1 was determined by means of a two-dimensional matrix of sensors whose number and arrangement correspond to those of the individual fields in FIG. 1.

(6) Every individual sensor detects the pressure on the skin of the patient. The pressure pattern comprises white and black boxes 110, with each white box corresponding to a pressure value which lies below a limit value and each black box corresponding to a pressure value which lies above a limit value. The longitudinal coordinate represents the lateral direction of the sensor matrix in the direction of the arm and the ordinate, i.e. the circumferential coordinate, represents the extent along the circumference of the arm around which the bandage is wound.

(7) As can be seen from FIG. 1, two-dimensional patterns 100 of pressure values generated at the same time can be generated in which spatial zones having large pressure values can be differentiated from spatial zones having low pressure values.

(8) A color form of the fields is furthermore conceivable which could provide a conclusion on the level of the pressure per sensor element.

(9) The measurement with optical, thermal or other sensors delivers similar functional patterns of the shunt.

(10) The pattern shown in FIG. 1 can be stored in a memory and can be used as a reference for future measurements. If they differ from the reference pattern, this can be evaluated as an indication of a flow change through the shunt.

(11) The pattern can always be recorded at a specific point in time for purposes of comparability, for example on or directly after the occurrence of the R wave of the ECG.

(12) An evaluation unit can carry out the comparison between the recorded pattern and a reference pattern; the evaluation unit provides the result of the evaluation for recall or transmits it to a receiver, e.g. in a dialysis center. The evaluation can generally take place directly in the bandage or also remote therefrom. In the latter case, it is not the evaluation which is transmitted by means of a transmission unit, but the measured values.

(13) In a preferred embodiment of the invention, the evaluation unit, e.g. in the form of a microcontroller, the memory and the sensors are integrated in or arranged at the bandage.

(14) Such a bandage is shown by the reference numeral 200 in FIG. 2. It can be used for protecting the shunt from external influences in the dialysis-free times. The bandage 200 is thus multi-functional in that, on the one hand, it provides a mechanical protection of the shunt and, on the other hand, carries out a multi-dimensional detection of at least one parameter which allows conclusions on the state of the shunt.

(15) The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims.