RHEOPLETHYSMOGRAPHIC DEVICE AND METHOD OF OPERATION

• US 3,742,936 A
• Filed: 10/21/1970
• Issued: 07/03/1973
• Est. Priority Date: 10/23/1969
• Status: Expired due to Term

• Current Assignee: Jean Marie Michel Paul Blanie, Jean Marie Rene (Bretigny-Sur-Orge Demange
• Original Assignee: Jean Marie Michel Paul Blanie, Jean Marie Rene (Bretigny-Sur-Orge Demange
• Inventors: Blanie, Jean Marie Michel Paul, Demange, Jean Marie Rene (Bretigny-sur-Orge
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/082,578
• Time in Patent Office: 986 Days
• Field of Search: 128/2.5Q,2.5R,2.5V,2.8Q,2.8R,2.1Z 235/186,189,190,191,192
• US Class Current: 600/526
• CPC Class Codes: A61B 5/0535 Impedance plethysmography for measuring blood flow A61B5/0295
• CPC Class Codes: A61B 5/0809 by impedance pneumography
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance

Abstract

A rheoplethysmographic device (inductance plethysmograph) comprising a high frequency electric generator of which the voltage is applied to a subject by means of a pair of injection electrodes, characterised by the fact that the injection electrodes are placed in series with at least one current setting impedance interposed between the subject and the generator, at least one pair of collector electrodes being placed on the subject within the zone subjected to voltage by the injection electrodes, the voltage collected between the electrodes of each pair and that collected between one pair of points of a current setting impedance being subsequently led after amplification to a differential device and then to an indicating device for measurement, control recording or transmission, the position of the said pair of points being such that the voltage received between them substantially balances the mean voltage between the corresponding pair of collector electrodes so that after amplification of each of the said voltages and passage through the differential device, the output voltage varies about zero.

Claims

1. A rheoplethysmographic device comprising:

a. a high frequency generator, b. a pair of injection electrode means for applying the voltage generated by the generator to a subject, c. at least one pair of collector electrodes for placement on the subject within the zone subjected to voltage by the injection electrodes, d. at least one current setting resistive element connected in series with the injection electrodes and the generator, e. means for balancing the voltage collected between the collector electrodes and the voltage collected between one pair of selected points on said current setting resistive element, said balancing means including an amplifier connected across said collector electrodes and an amplifier connected across the pair of selected points and a first differential device connected to said amplifiers f. an indicating device connected to said differential device, g. the position of the pair of selected points being adjustably positioned whereby the voltage received between the selected points substantially balances the mean voltage between the corresponding pair of collector electrodes so that after amplification of each of the voltages and passage through the differential device, the output voltage to said indicating device varies about zero.

2. A device according to claim 1 including means for rectifying the voltage collected between the electrodes of each pair and that collected between each pair of selected points before being fed to the differential device.

3. A device according to claim 1 wherein at least the collector electrodes are in the shape of narrow strips which permits their placement substantially along equipotential lines.

4. A device according to claim 1 comprising a plurality of pairs of collector electrodes and corresponding amplification channels.

5. A device according to claim 4 including a plurality of pairs of movable voltage receiving points arranged on said at least one current setting resistive element and corresponding amplification channels, said plurality of pairs of points being equal in numer to the number of pairs of collector electrodes.

6. A device according to claim 1 including before said indicating device filter means for eliminating the components of frequencies corresponding to phenomena other than those rheoplethysmographic components which are to be studied.

7. A device according to claim 1 including a second pair of collector electrodes, a second differential device connected to said second pair of collector electrodes, a third differential device connected to said first and second differential devices, a means for adjusting the signal level to said third differential device and said third differential device connected to said indicating device.

8. A device according to claim 1, including a different system of monitoring an organic phenomenon, means for receiving a signal from said different system of monitoring an organic phenomenon, and means for trimming, shaping and superimposing the signal transmitted to the indicating device.

9. A device accoRding to claim 8 wherein the said different signal is a phonocardiographic signal.

10. A device according to claim 8 wherein the said different signal is a signal of electric activity.

11. A device according to claim 10 wherein the signal of electric activity is collected from at least two electrodes, at least one of which is an electrode of the rheoplethysmographic device.

12. A device according to claim 11 wherein the different signal is an electrocardiographic signal.

13. A rheoplethsymographic method comprising the steps of:

a. placing a pair of injection electrodes on a subject, b. placing a pair of collector electrodes on the subject, c. generating a high frequency voltage by means of a generator, d. applying the voltage to the subject through the pair of injection electrodes, e. connecting a current setting resistive element in series with the injection electrodes and the generator, f. collecting voltages from selected points of said resistive element, g. balancing the voltage collected between the collector electrodes and the voltage collected between a pair of points on the current setting resistive element, and h. connecting an indicator to the collector electrodes and points and indicating changes in the subject'"'"''"'"'s body represented by changes in voltage across the collector electrodes.

14. A method as defined in claim 13 used to measure the systolic volume wherein the electrode placing includes placing one of the injection electrodes above the subject'"'"''"'"'s sternal notch at the level of the neck, placing the other injection electrode at the base of the subject'"'"''"'"'s thorax on the left side substantially parallel to the costal rim, and placing the collector electrodes on the face of the thorax at the level of the aortic projection facing the aorta.