US 2019/0239756 A1Published application

Method And Apparatus For Determination Of Left Ventricular Stroke Volume And Cardiac Output Using The Arteries Of The Forearm By Means Of Integration Technique

AssigneeCordeus, Inc.

InventorDonald P. Bernstein

Life of this patent

Estimating the term…

Loading patent…

Abstract

An apparatus a method for determining stroke volume by bioimpedance from a person having two or more spaced apart alternating current flow electrodes positionable on a person and two or more spaced apart voltage sensing electrodes positionable on the person and between the alternating current flow electrodes. A constant magnitude alternating current source is electrically connectable to the alternating current flow electrodes. A voltmeter is electrically connectable to the voltage sensing electrodes and configured to generate a voltage signal Z from a voltage sensed by the voltage sensing electrodes. A processing unit is electrically connectable with the voltmeter and configured to determine a stroke volume (SV) using the voltage signal Z and at least one of six equations.

Claims21

Dependent claims

An apparatus for determining stroke volume by bioimpedance from a person, comprising:

two or more spaced apart alternating current flow electrodes positionable on a person;
two or more spaced apart voltage sensing electrodes positionable on the person and between the alternating current flow electrodes;
a constant magnitude alternating current source electrically connectable to the alternating current flow electrodes;
a voltmeter electrically connectable to the voltage sensing electrodes and configured to generate a voltage signal Z from a voltage sensed by the voltage sensing electrodes;
a processing unit electrically connectable with the voltmeter and configured to determine a stroke volume (SV) using the voltage signal Z and at least one of the following six equations:
Q
.
Z
=
C
·
[
∫
t
B
t
0

+
dZ

(
t
)
dt

dt
+
∫
t
0
t
X


-
dZ

(
t
)
dt

dt

]
Z
0
=
C
·
dZ

(
t
)
total
Z
0
(
1
)
Q
.
Z
=
C
·
+
dZ

(
t
)
+

-
dZ

(
t
)

Z
0
=
C
·
dZ

(
t
)
total
Z
0
(
2
)
SV
Z
=
C
·
[
∫
t
B
t
0

+
dZ

(
t
)

dt
+
∫
t
0
t
X


-
dZ

(
t
)

dt

]
Z
0
=
C
·
[
+
Z
+

-
Z

]
Z
0
(
3
)
SV
Z
=
C
·
[
+
Z
+

-
Z

]
Z
0
=
C
·
Z
total
Z
0
(
4
)
SV
Z
=
Q
=
C
·
∫
t
B
t
X

dZ

(
t
)

dt
total
Z
0
=
C
·
Z
total
Z
0
(
5
)
SV
=
C
·
∫
t
B
t
X

dZ

(
t
)

dt
Z
0
=
C
·
Z
Z
0
(
6
)
wherein:
{dot over (Q)}=impedance-derived blood flow velocity (mL/s)
∫=definite integral over time intervals from tB to t0 and t0 to tX that collectively are a systolic flow time, where tB is a beginning point of cardiogenically-induced transradioulnar impedance pulse, t0 is a maximum point of cardiogenically-induced transradioulnar impedance pulse, and tX is an ending point of cardiogenically-induced transradioulnar impedance pulse
•

dZ

(
t
)
dt
=
cardiogenically

-

induced


rate


of


change


of


the

transradioulnar


impedance


pulse


variation
•

dZ

(
t
)
dt
ma


x
=
peak


rate


of


change


of


the


cardiogenically

-

induced

transradioulnar


impedance


pulse


variation
dZ(t)=cardiogenically-induced transradioulnar impedance pulse variation
C=constant person-specific mass-based allometric equivalent of volume
QZ=transradioulnar impedance-derived stroke volume
Z0=quasi-static transradioulnar base impedance.

334 more elements

A method of determining stroke volume by bioimpedance from a person, comprising:

positioning two or more spaced apart alternating current flow electrodes on the forearm of a person;
positioning two or more spaced apart voltage sensing electrodes on the forearm of the person and between the alternating current flow electrodes;
providing a constant magnitude alternating current flow through the alternating current flow electrodes;
measuring a voltage Z between the voltage sensing electrodes;
determining a stroke volume (SV) using the measured voltage Z and at least one of the following six equations:
Q
.
Z
=
C
·
[
∫
t
B
t
0

+
dZ

(
t
)
dt

dt
+
∫
t
0
t
X


-
dZ

(
t
)
dt

dt

]
Z
0
=
C
·
dZ

(
t
)
total
Z
0
(
1
)
Q
.
Z
=
C
·
+
dZ

(
t
)
+

-
dZ

(
t
)

Z
0
=
C
·
dZ

(
t
)
total
Z
0
(
2
)
SV
Z
=
C
·
[
∫
t
B
t
0

+
dZ

(
t
)

dt
+
∫
t
0
t
X


-
dZ

(
t
)

dt

]
Z
0
=
C
·
[
+
Z
+

-
Z

]
Z
0
(
3
)
SV
Z
=
C
·
[
+
Z
+

-
Z

]
Z
0
=
C
·
Z
total
Z
0
(
4
)
SV
Z
=
Q
=
C
·
∫
t
B
t
X

dZ

(
t
)

dt
total
Z
0
=
C
·
Z
total
Z
0
(
5
)
SV
=
C
·
∫
t
B
t
X

dZ

(
t
)

dt
Z
0
=
C
·
Z
Z
0
(
6
)
wherein:
{dot over (Q)}Z=impedance-derived blood flow velocity (mL/s)
∫=definite integral over time intervals from tB to t0 and t0 to tX that collectively are a systolic flow time, where tB is a beginning point of cardiogenically-induced transradioulnar impedance pulse, t0 is a maximum point of cardiogenically-induced transradioulnar impedance pulse, and tX is an ending point of cardiogenically-induced transradioulnar impedance pulse
•

dZ

(
t
)
dt
=
cardiogenically

-

induced


rate


of


change


of


the

transradioulnar


impedance


pulse


variation
•

dZ

(
t
)
dt
ma


x
=
peak


rate


of


change


of


the


cardiogenically

-

induced

transradioulnar


impedance


pulse


variation
dZ(t)=cardiogenically-induced transradioulnar impedance pulse variation
C=constant person-specific mass-based allometric equivalent of volume
QZ=transradioulnar impedance-derived stroke volume
Z0=quasi-static transradioulnar base impedance.

334 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/889,089Filed 5 Feb 2018
Published: 8 Aug 2019
Term ends: Not estimatedThe source records don’t support an estimate.

Classification23 codes

A61B 5/02028
Detecting, measuring or recording for evaluating the cardiovascular system, e.g. pulse, heart rate, blood pressure or blood flow: determining…
A61B 5/0245
Measuring pulse rate or heart rate: by using sensing means generating electric signals, i.e. ECG signals
A61B 5/029
Measuring blood flow: measuring blood output from the heart, e.g. minute volume
A61B 5/0295
Measuring blood flow: using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood…