U.S. patent application number 16/740888 was filed with the patent office on 2020-05-14 for intravenous access device detecting intravenous infiltration and in-vein placement.
The applicant listed for this patent is VANDERBILT UNIVERSITY. Invention is credited to Franz Baudenbacher, Richard Boyer, Colleen Brophy, Susan S. Eagle, Kyle Mitchell Hocking.
Application Number | 20200146566 16/740888 |
Document ID | / |
Family ID | 70552285 |
Filed Date | 2020-05-14 |
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United States Patent
Application |
20200146566 |
Kind Code |
A1 |
Eagle; Susan S. ; et
al. |
May 14, 2020 |
INTRAVENOUS ACCESS DEVICE DETECTING INTRAVENOUS INFILTRATION AND
IN-VEIN PLACEMENT
Abstract
Aspects of the invention relates to systems and methods for
monitoring an intravenous (IV) line functionality of an IV device.
The system includes an IV catheter to be inserted into the vein of
the living subject, at least one pressure sensor in fluid
communication with the IV catheter to acquire peripheral venous
signals; and a processing device. The processing device receives
the peripheral venous signals from the pressure sensor, performs a
spectral analysis on the peripheral venous signals to obtain a
peripheral venous pressure frequency spectrum, and determines an IV
line functionality of the IV catheter in real time, wherein the IV
line functionality of the IV catheter indicates IV infiltration
when amplitude decreases greater than a first threshold are
detected from the peaks of the peripheral venous pressure frequency
spectrum.
Inventors: |
Eagle; Susan S.; (Nashville,
TN) ; Brophy; Colleen; (Nashville, TN) ;
Hocking; Kyle Mitchell; (Nashville, TN) ;
Baudenbacher; Franz; (Franklin, TN) ; Boyer;
Richard; (Nashville, TN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VANDERBILT UNIVERSITY |
Nashville |
TN |
US |
|
|
Family ID: |
70552285 |
Appl. No.: |
16/740888 |
Filed: |
January 13, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15547935 |
Aug 1, 2017 |
10531799 |
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PCT/US2016/016420 |
Feb 3, 2016 |
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16740888 |
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14853504 |
Sep 14, 2015 |
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15547935 |
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62111337 |
Feb 3, 2015 |
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62049829 |
Sep 12, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 5/16854 20130101;
A61B 5/02152 20130101; A61B 5/7257 20130101; A61B 5/7235 20130101;
A61M 5/158 20130101; A61M 2005/1588 20130101 |
International
Class: |
A61B 5/0215 20060101
A61B005/0215; A61B 5/00 20060101 A61B005/00; A61M 5/168 20060101
A61M005/168; A61M 5/158 20060101 A61M005/158 |
Claims
1. An intravenous (IV) system, comprising: an IV catheter,
configured to be inserted into a vein of a living subject; at least
one pressure sensor in fluid communication with the IV catheter,
configured to acquire, from the vein of the living subject,
peripheral venous signals; and a processing device communicatively
connected to the at least one pressure sensor, configured to:
receive the peripheral venous signals from the at least one
pressure sensor; perform a spectral analysis on the peripheral
venous signals to obtain a peripheral venous pressure frequency
spectrum; and determine an IV line functionality of the IV catheter
in real time, wherein the IV line functionality of the IV catheter
indicates IV infiltration when amplitude decreases greater than a
first threshold are detected from the peaks of the peripheral
venous pressure frequency spectrum.
2. The system of claim 1, wherein the IV infiltration indicates
occlusion or malposition of the IV catheter.
3. The system of claim 1, wherein the spectral analysis is a
spectral fast Fourier transform (FFT) analysis.
4. The system of claim 3, wherein the IV line functionality is
determined by: obtaining a plurality of baseline peaks {B.sub.N-1}
on a baseline peripheral venous pressure frequency spectrum,
wherein N is a positive integer, and the plurality of baseline
peaks {B.sub.N-1} respectively corresponds to a plurality of
frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
B.sub.N-1 is a function of F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1
(F.sub.N-1), wherein F.sub.N is greater than F.sub.N-1; obtaining a
plurality of peaks {P.sub.N-1} on the peripheral venous pressure
frequency spectrum, wherein the plurality of peaks {P.sub.N-1}
correspond to the plurality of frequencies {F.sub.0, F.sub.1, . . .
, F.sub.N}, such that P.sub.N-1 is a function of F.sub.N-1
satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV
line functionality in real time by comparing the amplitudes of the
peaks {P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
5. The system of claim 4, wherein the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring, by the at
least one pressure sensor, the peripheral venous signals from the
vein of the living subject at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
6. The system of claim 1, further comprising: a tubing having a
first end and an opposite, second end, wherein the first end is
connectable to the fluid source, and the second end is connected to
the IV catheter; and a port device in fluid communication with the
tubing, located between the first and second ends of the tubing;
wherein the at least one pressure sensor is in fluid communication
with the tubing through the port device.
7. An intravenous (IV) system, comprising: an IV device configured
to acquire, from a vein of a living subject, peripheral venous
signals; and a processing device communicatively connected to the
IV device, configured to: receive the peripheral venous signals
from the IV device; perform a spectral analysis on the peripheral
venous signals to obtain a peripheral venous pressure frequency
spectrum; and determine an IV line functionality of the IV device
in real time, wherein the IV line functionality of the IV device is
determined to indicate IV infiltration when amplitude decreases
greater than a first threshold are detected from the peaks of the
peripheral venous pressure frequency spectrum, wherein the IV
device comprises: an IV catheter, configured to be inserted into
the vein of the living subject; and a tubing having a first end and
an opposite, second end, wherein the first end is connectable to a
fluid source, and the second end is connected to the IV
catheter.
8. The system of claim 7, wherein the processing device is a
computing device.
9. The system of claim 7, wherein the spectral analysis is a
spectral fast Fourier transform (FFT) analysis.
10. The system of claim 9, wherein the IV line functionality is
determined by: obtaining a plurality of baseline peaks {B.sub.N-1}
on a baseline peripheral venous pressure frequency spectrum,
wherein N is a positive integer, and the plurality of baseline
peaks {B.sub.N-1} respectively corresponds to a plurality of
frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
B.sub.N-1 is a function of F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1
(F.sub.N-1), wherein F.sub.N is greater than F.sub.N-1; obtaining a
plurality of peaks {P.sub.N-1} on the peripheral venous pressure
frequency spectrum, wherein the plurality of peaks {P.sub.N-1}
correspond to the plurality of frequencies {F.sub.0, F.sub.1, . . .
, F.sub.N}, such that P.sub.N-1 is a function of F.sub.N-1
satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV
line functionality of the IV device in real time by comparing the
amplitudes of the peaks {P.sub.N-1} to that of the baseline peaks
{B.sub.N-1} respectively.
11. The system of claim 10, wherein the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring, by the IV
device, the peripheral venous signals from the vein of the living
subject at an earlier time period; and processing the peripheral
venous signals acquired at the earlier time period by the spectral
FFT analysis to obtain the baseline peripheral venous pressure
frequency spectrum.
12. The system of claim 7, wherein the IV device further comprises:
a port device in fluid communication with the tubing, located
between the first and second ends of the tubing; and at least one
pressure sensor in fluid communication with the tubing through the
port device, configured to obtain the peripheral venous signals by
measuring fluid pressures in the port device.
13. The system of claim 7, wherein the IV infiltration indicates
occlusion or malposition of the IV catheter.
14. A method for monitoring an intravenous (IV) line functionality
of an IV device, wherein the IV device comprises an IV catheter,
configured to be inserted into a vein of the living subject; and a
tubing having a first end and an opposite, second end, wherein the
first end is connectable to a fluid source, and the second end is
connected to the IV catheter, the method comprising: acquiring,
from the IV catheter, peripheral venous signals, wherein the IV
catheter is configured to be inserted in the vein of the living
subject; performing, by a processing device communicatively
connected to the IV device, a spectral analysis on the acquired
peripheral venous signals to obtain a peripheral venous pressure
frequency spectrum; and determining, by the processing device, the
IV line functionality of the IV device in real time.
15. The method of claim 14, wherein the spectral analysis is a
spectral fast Fourier transform (FFT) analysis.
16. The method of claim 15, wherein the step of determining the IV
line functionality comprises: obtaining a plurality of baseline
peaks {B.sub.N-1} on a baseline peripheral venous pressure
frequency spectrum, wherein N is a positive integer, and the
plurality of baseline peaks {B.sub.N-1} respectively corresponds to
a plurality of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N},
such that B.sub.N-1 is a function of F.sub.N-1 satisfying
B.sub.N-1=B.sub.N-1 (F.sub.N-1), wherein F.sub.N is greater than
F.sub.N-1; obtaining a plurality of peaks {P.sub.N-1} on the
peripheral venous pressure frequency spectrum, wherein the
plurality of peaks {P.sub.N-1} correspond to the plurality of
frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
P.sub.N-1 is a function of F.sub.N-1 satisfying P.sub.N-1=P.sub.N-1
(F.sub.N-1); and determining the IV line functionality of the IV
device in real time by comparing the amplitudes of the peaks
{P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
17. The method of claim 15, wherein the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring the
peripheral venous signals from the IV catheter at an earlier time
period; and processing the peripheral venous signals acquired at
the earlier time period by the spectral FFT analysis to obtain the
baseline peripheral venous pressure frequency spectrum.
18. The method of claim 14, wherein the IV line functionality of
the IV device is determined to indicate IV infiltration when
amplitude decreases greater than a first threshold are detected
from the peaks of the peripheral venous pressure frequency
spectrum.
19. The system of claim 18, wherein the IV infiltration indicates
occlusion or malposition of the IV catheter.
20. The method of claim 14, wherein the IV device further
comprises: a port device in fluid communication with the tubing,
located between the first and second ends of the tubing; and at
least one pressure sensor in fluid communication with the tubing
through the port device, configured to obtain the peripheral venous
signals by measuring fluid pressures in the port device.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
[0001] This application is a continuation application of, and
claims benefit of U.S. patent application Ser. No. 15/547,935,
filed Aug. 1, 2017, now allowed, which is a national stage entry of
PCT Application Serial No. PCT/US2016/016420, filed Feb. 3, 2016,
which claims priority to and the benefit of U.S. Provisional Patent
Application Ser. No. 62/111,337, filed Feb. 3, 2015 and is a
continuation-in-part of U.S. patent application Ser. No.
14/853,504, filed Sep. 14, 2015, which claims priority to and the
benefit of U.S. Provisional Patent Application Ser. No. 62/049,829,
filed Sep. 12, 2014. All the above disclosures are incorporated
herein in their entireties by reference.
[0002] Some references, which may include patents, patent
applications and various publications, are cited and discussed in
the description of this invention. The citation and/or discussion
of such references is provided merely to clarify the description of
the present invention and is not an admission that any such
reference is "prior art" to the invention described herein. All
references cited and discussed in this specification are
incorporated herein by reference in their entireties and to the
same extent as if each reference was individually incorporated by
reference.
FIELD OF THE INVENTION
[0003] The present invention relates generally to intravenous (IV)
therapy, and more specifically, the present invention relates to
systems and methods for monitoring intravascular placement of an IV
catheter and detecting IV infiltration, and applications of the
same.
BACKGROUND OF THE INVENTION
[0004] While seemingly simple, proper intravascular placement of an
intravenous (IV) catheter is mandatory for effective IV volume
resuscitation and IV pharmacologic administration. Malpositioning
or misplacing of IV catheters may occur at any time during
hospitalization or when a patient is in a status under the
potential need of IV volume resuscitation and/or IV pharmacologic
administration. For example, ambulatory patients may inadvertently
displace the catheter, often secured with tape; patients in the
operating room setting often have their arms tucked in sheets, away
from the operative field, precluding inspection of the IV insertion
site for signs of infiltration; and pediatric patients often have
IV catheters secured with devices to prevent patient tampering,
which also obscures the IV insertion site.
[0005] Malpositioning of a peripheral IV catheter into the
extravascular space precludes the patient from receiving necessary
resuscitative therapy. Fluid administration into subcutaneous
tissue or fascia may result in compartment syndrome and loss of the
extremity. Tissue necrosis and gangrene may result from tissue
infiltration of vasoactive medications.
[0006] Therefore, a heretofore unaddressed need exists in the art
to address the aforementioned deficiencies and inadequacies.
SUMMARY OF THE INVENTION
[0007] One aspect of the invention relates to an intravenous (IV)
system, comprising an IV catheter, configured to be inserted into a
vein of a living subject; at least one pressure sensor in fluid
communication with the IV catheter, configured to acquire, from the
vein of the living subject, peripheral venous signals; and a
processing device communicatively connected to the at least one
pressure sensor.
[0008] The processing device is configured to receive the
peripheral venous signals from the at least one pressure sensor;
perform a spectral analysis on the peripheral venous signals to
obtain a peripheral venous pressure frequency spectrum; and
determine an IV line functionality of the IV catheter in real time,
wherein the IV line functionality of the IV catheter indicates IV
infiltration when amplitude decreases greater than a first
threshold are detected from the peaks of the peripheral venous
pressure frequency spectrum.
[0009] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0010] In certain embodiments, the spectral analysis is a spectral
fast Fourier transform (FFT) analysis.
[0011] In certain embodiments, the IV line functionality is
determined by obtaining a plurality of baseline peaks {B.sub.N-1}
on a baseline peripheral venous pressure frequency spectrum,
wherein N is a positive integer, and the plurality of baseline
peaks {B.sub.N-1} respectively corresponds to a plurality of
frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
B.sub.N-1 is a function of F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1
(F.sub.N-1), wherein F.sub.N is greater than F.sub.N-1; obtaining a
plurality of peaks {P.sub.N-1} on the peripheral venous pressure
frequency spectrum, wherein the plurality of peaks {P.sub.N-1}
correspond to the plurality of frequencies {F.sub.0, F.sub.1, . . .
, F.sub.N}, such that P.sub.N-1 is a function of F.sub.N-1
satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV
line functionality in real time by comparing the amplitudes of the
peaks {P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
[0012] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by acquiring, by the at
least one pressure sensor, the peripheral venous signals from the
vein of the living subject at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
[0013] In certain embodiments, the system further comprises a
tubing having a first end and an opposite, second end, wherein the
first end is connectable to the fluid source, and the second end is
connected to the IV catheter; and a port device in fluid
communication with the tubing, located between the first and second
ends of the tubing; wherein the at least one pressure sensor is in
fluid communication with the tubing through the port device.
[0014] Another aspect of the invention also relates to an IV system
comprising an IV device configured to acquire, from a vein of a
living subject, peripheral venous signals; and a processing device
communicatively connected to the IV device. The processing device
is configured to receive the peripheral venous signals from the IV
device; perform a spectral analysis on the peripheral venous
signals to obtain a peripheral venous pressure frequency spectrum;
and determine an IV line functionality of the IV device in real
time, wherein the IV line functionality of the IV device is
determined to indicate IV infiltration when amplitude decreases
greater than a first threshold are detected from the peaks of the
peripheral venous pressure frequency spectrum.
[0015] In certain embodiments, the IV device comprises an IV
catheter, configured to be inserted into the vein of the living
subject; and a tubing having a first end and an opposite, second
end, wherein the first end is connectable to a fluid source, and
the second end is connected to the IV catheter.
[0016] In certain embodiments, the processing device is a computing
device.
[0017] In certain embodiments, the spectral analysis is a spectral
fast Fourier transform (FFT) analysis.
[0018] In certain embodiments, the IV line functionality is
determined by obtaining a plurality of baseline peaks {B.sub.N-1}
on a baseline peripheral venous pressure frequency spectrum,
wherein N is a positive integer, and the plurality of baseline
peaks {B.sub.N-1} respectively corresponds to a plurality of
frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
B.sub.N-1 is a function of F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1
(F.sub.N-1), wherein F.sub.N is greater than F.sub.N-1; obtaining a
plurality of peaks {P.sub.N-1} on the peripheral venous pressure
frequency spectrum, wherein the plurality of peaks {P.sub.N-1}
correspond to the plurality of frequencies {F.sub.0, F.sub.1, . . .
, F.sub.N}, such that P.sub.N-1 is a function of F.sub.N-1
satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV
line functionality of the IV device in real time by comparing the
amplitudes of the peaks {P.sub.N-1} to that of the baseline peaks
{B.sub.N-1} respectively.
[0019] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by acquiring, by the IV
device, the peripheral venous signals from the vein of the living
subject at an earlier time period; and processing the peripheral
venous signals acquired at the earlier time period by the spectral
FFT analysis to obtain the baseline peripheral venous pressure
frequency spectrum.
[0020] In certain embodiments, the IV device further comprises a
port device in fluid communication with the tubing, located between
the first and second ends of the tubing; and at least one pressure
sensor in fluid communication with the tubing through the port
device, configured to obtain the peripheral venous signals by
measuring fluid pressures in the port device.
[0021] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0022] Yet another aspect of the invention provides a method for
monitoring an intravenous (IV) line functionality of an IV device.
The IV device comprises an IV catheter, configured to be inserted
into a vein of the living subject; and a tubing having a first end
and an opposite, second end, wherein the first end is connectable
to a fluid source, and the second end is connected to the IV
catheter.
[0023] The method includes acquiring, from the IV catheter,
peripheral venous signals, wherein the IV catheter is configured to
be inserted in the vein of the living subject; performing, by a
processing device communicatively connected to the IV device, a
spectral analysis on the acquired peripheral venous signals to
obtain a peripheral venous pressure frequency spectrum; and
determining, by the processing device, the IV line functionality of
the IV device in real time.
[0024] In certain embodiments, the spectral analysis is a spectral
fast Fourier transform (FFT) analysis.
[0025] In certain embodiments, said determining the IV line
functionality comprises obtaining a plurality of baseline peaks
{B.sub.N-1} on a baseline peripheral venous pressure frequency
spectrum, wherein N is a positive integer, and the plurality of
baseline peaks {B.sub.N-1} respectively corresponds to a plurality
of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such that
B.sub.N-1 is a function of F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1
(F.sub.N-1), wherein F.sub.N is greater than F.sub.N-1; obtaining a
plurality of peaks {P.sub.N-1} on the peripheral venous pressure
frequency spectrum, wherein the plurality of peaks {P.sub.N-1}
correspond to the plurality of frequencies {F.sub.0, F.sub.1, . . .
, F.sub.N}, such that P.sub.N-1 is a function of F.sub.N-1
satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV
line functionality of the IV device in real time by comparing the
amplitudes of the peaks {P.sub.N-1} to that of the baseline peaks
{B.sub.N-1} respectively.
[0026] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by acquiring the peripheral
venous signals from the IV catheter at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
[0027] In certain embodiments, the IV line functionality of the IV
device is determined to indicate IV infiltration when amplitude
decreases greater than a first threshold are detected from the
peaks of the peripheral venous pressure frequency spectrum.
[0028] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0029] In certain embodiments, the IV device further comprises a
port device in fluid communication with the tubing, located between
the first and second ends of the tubing; and at least one pressure
sensor in fluid communication with the tubing through the port
device, configured to obtain the peripheral venous signals by
measuring fluid pressures in the port device.
[0030] In one aspect, the present invention relates to an
intravenous (IV) system. In certain embodiments, the system
includes: an IV catheter, configured to be inserted into a vein of
a living subject; a fluid controlling device in fluid communication
with the IV catheter, configured to control fluid flow from a fluid
source to the IV catheter; at least one pressure sensor in fluid
communication with the IV catheter, configured to acquire, from the
vein of the living subject, peripheral venous signals; and a
processing device communicatively connected to the at least one
pressure sensor. The processing device is configured to: receive
the peripheral venous signals from the at least one pressure
sensor; perform a spectral analysis on the peripheral venous
signals to obtain a peripheral venous pressure frequency spectrum;
perform a statistical analysis on amplitudes of peaks of the
peripheral venous pressure frequency spectrum to determine an IV
line functionality of the IV catheter in real time, where the IV
line functionality of the IV catheter indicates IV infiltration
when amplitude decreases greater than a first threshold are
detected from the peaks of the peripheral venous pressure frequency
spectrum; and when the IV line functionality of the IV catheter
indicates IV infiltration, control the fluid controlling device to
stop the fluid flow from the fluid source to the IV catheter.
[0031] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0032] In certain embodiments, the spectral analysis is a spectral
fast Fourier transform (FFT) analysis.
[0033] In certain embodiments, the statistical analysis includes:
obtaining a plurality of baseline peaks {B.sub.N-1} on a baseline
peripheral venous pressure frequency spectrum, wherein N is a
positive integer, and the plurality of baseline peaks {B.sub.N-1}
respectively corresponds to a plurality of frequencies {F.sub.0,
F.sub.1, . . . , F.sub.N}, such that B.sub.N-1 is a function of
F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1 (F.sub.N-1), wherein
F.sub.N is greater than F.sub.N-1; obtaining a plurality of peaks
{P.sub.N-1} on the peripheral venous pressure frequency spectrum,
wherein the plurality of peaks {P.sub.N-1} correspond to the
plurality of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such
that P.sub.N-1 is a function of F.sub.N-1 satisfying
P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV line
functionality in real time by comparing the amplitudes of the peaks
{P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
[0034] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring, by the at
least one pressure sensor, the peripheral venous signals from the
vein of the living subject at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
[0035] In certain embodiments, the IV system further includes: a
tubing having a first end and an opposite, second end, wherein the
first end is connectable to the fluid source, and the second end is
connected to the IV catheter; and a port device in fluid
communication with the tubing, located between the first and second
ends of the tubing, where the at least one pressure sensor is in
fluid communication with the tubing through the port device.
[0036] Another aspect of the present invention relates to an IV
system, which includes an IV device and a processing device
communicatively connected to the IV device. The IV device is
configured to acquire, from a vein of a living subject, peripheral
venous signals. The processing device is configured to: receive the
peripheral venous signals from the IV device; perform a spectral
analysis on the peripheral venous signals to obtain a peripheral
venous pressure frequency spectrum; and perform a statistical
analysis on amplitudes of peaks of the peripheral venous pressure
frequency spectrum to determine an IV line functionality of the IV
device in real time.
[0037] In certain embodiments, the processing device is a computing
device.
[0038] In certain embodiments, the spectral analysis is a spectral
FFT analysis.
[0039] In certain embodiments, the statistical analysis includes:
obtaining a plurality of baseline peaks {B.sub.N-1} on a baseline
peripheral venous pressure frequency spectrum, wherein N is a
positive integer, and the plurality of baseline peaks {B.sub.N-1}
respectively corresponds to a plurality of frequencies {F.sub.0,
F.sub.1, . . . , F.sub.N}, such that B.sub.N-1 is a function of
F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1 (F.sub.N-1), wherein
F.sub.N is greater than F.sub.N-1; obtaining a plurality of peaks
{P.sub.N-1} on the peripheral venous pressure frequency spectrum,
wherein the plurality of peaks {P.sub.N-1} correspond to the
plurality of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such
that P.sub.N-1 is a function of F.sub.N-1 satisfying
P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV line
functionality in real time by comparing the amplitudes of the peaks
{P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
[0040] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring, by the at
least one pressure sensor, the peripheral venous signals from the
vein of the living subject at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
[0041] In certain embodiments, the IV line functionality of the IV
device is determined to indicate IV infiltration when amplitude
decreases greater than a first threshold are detected from the
peaks of the peripheral venous pressure frequency spectrum.
[0042] In certain embodiments, the IV device includes: an IV
catheter, configured to be inserted into the vein of the living
subject; a tubing having a first end and an opposite, second end,
wherein the first end is connectable to a fluid source, and the
second end is connected to the IV catheter; a port device in fluid
communication with the tubing, located between the first and second
ends of the tubing; and at least one pressure sensor in fluid
communication with the tubing through the port device, configured
to obtain the peripheral venous signals by measuring fluid
pressures in the port device.
[0043] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0044] In certain embodiments, the IV device further includes a
fluid controlling device in fluid communication with the tubing,
located between the first and second ends of the tubing to control
fluid flow from the fluid source to the IV catheter. In certain
embodiments, the processing device is further configured to, when
the IV line functionality of the IV device is determined to
indicate IV infiltration, control the fluid controlling device to
stop the fluid flow from the fluid source to the IV catheter.
Alternatively, the processing device is further configured to, when
the IV line functionality of the IV device is determined to
indicate IV infiltration, control the fluid controlling device to
reduce a flow rate of the fluid flow from the fluid source to the
IV catheter, or generate an alert message.
[0045] A further aspect of the present invention relates to a
method for monitoring an IV line functionality of an IV device,
which includes: acquiring, from an IV catheter, peripheral venous
signals, wherein the IV catheter is configured to be inserted in a
vein of the living subject; performing a spectral analysis on the
acquired peripheral venous signals to obtain a peripheral venous
pressure frequency spectrum; and performing a statistical analysis
on amplitudes of peaks of the peripheral venous pressure frequency
spectrum to determine the IV line functionality of the IV device in
real time.
[0046] In certain embodiments, the spectral analysis is a spectral
FFT analysis.
[0047] In certain embodiments, the statistical analysis includes:
obtaining a plurality of baseline peaks {B.sub.N-1} on a baseline
peripheral venous pressure frequency spectrum, wherein N is a
positive integer, and the plurality of baseline peaks {B.sub.N-1}
respectively corresponds to a plurality of frequencies {F.sub.0,
F.sub.1, . . . , F.sub.N}, such that B.sub.N-1 is a function of
F.sub.N-1 satisfying B.sub.N-1=B.sub.N-1 (F.sub.N-1), wherein
F.sub.N is greater than F.sub.N-1; obtaining a plurality of peaks
{P.sub.N-1} on the peripheral venous pressure frequency spectrum,
wherein the plurality of peaks {P.sub.N-1} correspond to the
plurality of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N}, such
that P.sub.N-1 is a function of F.sub.N-1 satisfying
P.sub.N-1=P.sub.N-1 (F.sub.N-1); and determining the IV line
functionality in real time by comparing the amplitudes of the peaks
{P.sub.N-1} to that of the baseline peaks {B.sub.N-1}
respectively.
[0048] In certain embodiments, the baseline peripheral venous
pressure frequency spectrum is obtained by: acquiring, by the at
least one pressure sensor, the peripheral venous signals from the
vein of the living subject at an earlier time period; and
processing the peripheral venous signals acquired at the earlier
time period by the spectral FFT analysis to obtain the baseline
peripheral venous pressure frequency spectrum.
[0049] In certain embodiments, the IV line functionality of the IV
device is determined to indicate IV infiltration when amplitude
decreases greater than a first threshold are detected from the
peaks of the peripheral venous pressure frequency spectrum.
[0050] In certain embodiments, the IV infiltration indicates
occlusion or malposition of the IV catheter.
[0051] In certain embodiments, the IV device includes: an IV
catheter, configured to be inserted into the vein of the living
subject; a tubing having a first end and an opposite, second end,
wherein the first end is connectable to a fluid source, and the
second end is connected to the IV catheter; a port device in fluid
communication with the tubing, located between the first and second
ends of the tubing; at least one pressure sensor in fluid
communication with the tubing through the port device, configured
to obtain the peripheral venous signals by measuring fluid
pressures in the port device; and a fluid controlling device in
fluid communication with the tubing, located between the first and
second ends of the tubing to control fluid flow from the fluid
source to the IV catheter. In certain embodiments, the method
further includes: when the IV line functionality of the IV device
is determined to indicate IV infiltration, controlling the fluid
controlling device to stop the fluid flow from the fluid source to
the IV catheter.
[0052] In a further aspect, the present invention relates to a
method for monitoring an intravenous (IV) line functionality of an
IV device using the IV system as described above.
[0053] In certain embodiments, the system and method as described
above may be used for monitoring and detecting IV infiltration in
real time, thus preventing tissue damage to the patient.
[0054] These and other aspects of the present invention will become
apparent from the following description of the preferred
embodiments taken in conjunction with the following drawings,
although variations and modifications thereof may be affected
without departing from the spirit and scope of the novel concepts
of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] The accompanying drawings illustrate one or more embodiments
of the invention and, together with the written description, serve
to explain the principles of the invention. Wherever possible, the
same reference numbers are used throughout the drawings to refer to
the same or like elements of an embodiment.
[0056] FIG. 1 shows patients in need of IV volume resuscitation
according to certain embodiments of the present invention.
[0057] FIG. 2A shows a chart of line pressure of an IV tubing with
pump flow at 50 mL/hour according to certain embodiments of the
present invention.
[0058] FIG. 2B shows a result of IV infiltration for about 30
minutes according to certain embodiments of the present
invention.
[0059] FIG. 3A shows an IV system according to certain embodiments
of the present invention.
[0060] FIG. 3B shows an IV device according to certain embodiments
of the present invention.
[0061] FIG. 3C shows an IV device according to certain embodiments
of the present invention.
[0062] FIG. 4 shows a flowchart of a method for monitoring an IV
line functionality of an IV device according to certain embodiments
of the present invention.
[0063] FIG. 5 shows comparison of central venous pressure (CVP) and
peripheral venous pressure (PVP) according to certain embodiments
of the present invention.
[0064] FIG. 6 shows (A) a chart of the peripheral venous waveforms
and (B) the Fourier transformation of the signals according to
certain embodiments of the present invention.
[0065] FIG. 7 shows the conversion from the peripheral venous
signals to the peripheral venous pressure frequency spectrum
according to certain embodiments of the present invention.
[0066] FIG. 8 shows the peripheral venous pressure frequency
spectrum of (A) a functional IV and (B) an infiltrated IV according
to certain embodiments of the present invention.
[0067] FIG. 9A shows the ROC curves for detection of linear SSE
analysis on human beings according to certain embodiments of the
present invention.
[0068] FIG. 9B shows a table of the ROC curves and 95% confidence
interval (CI) for the data as shown in FIG. 9A according to certain
embodiments of the present invention.
[0069] FIG. 10A shows the ROC curves for spectral analysis on
porcines according to certain embodiments of the present
invention.
[0070] FIG. 10B shows a table of the ROC curves and 95% confidence
interval (CI) for the data as shown in FIG. 10A according to
certain embodiments of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0071] The invention will now be described more fully hereinafter
with reference to the accompanying drawings, in which exemplary
embodiments of the invention are shown. This invention may,
however, be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein. Rather,
these embodiments are provided so that this disclosure will be
thorough and complete, and will fully convey the scope of the
invention to those skilled in the art. Like reference numerals
refer to like elements throughout.
[0072] The terms used in this specification generally have their
ordinary meanings in the art, within the context of the invention,
and in the specific context where each term is used. Certain terms
that are used to describe the invention are discussed below, or
elsewhere in the specification, to provide additional guidance to
the practitioner regarding the description of the invention. For
convenience, certain terms may be highlighted, for example using
italics and/or quotation marks. The use of highlighting has no
influence on the scope and meaning of a term; the scope and meaning
of a term are the same, in the same context, whether or not it is
highlighted. It will be appreciated that the same thing can be said
in more than one way. Consequently, alternative language and
synonyms may be used for any one or more of the terms discussed
herein, nor is any special significance to be placed upon whether
or not a term is elaborated or discussed herein. Synonyms for
certain terms are provided. A recital of one or more synonyms does
not exclude the use of other synonyms. The use of examples anywhere
in this specification including examples of any terms discussed
herein is illustrative only, and in no way limits the scope and
meaning of the invention or of any exemplified term. Likewise, the
invention is not limited to various embodiments given in this
specification.
[0073] It will be understood that when an element is referred to as
being "on" another element, it can be directly on the other element
or intervening elements may be present there between. In contrast,
when an element is referred to as being "directly on" another
element, there are no intervening elements present. As used herein,
the term "and/or" includes any and all combinations of one or more
of the associated listed items.
[0074] It will be understood that, although the terms first,
second, third, etc. may be used herein to describe various
elements, components, regions, layers and/or sections, these
elements, components, regions, layers and/or sections should not be
limited by these terms. These terms are only used to distinguish
one element, component, region, layer or section from another
element, component, region, layer or section. Thus, a first
element, component, region, layer or section discussed below could
be termed a second element, component, region, layer or section
without departing from the teachings of the invention.
[0075] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising", or "includes"
and/or "including" or "has" and/or "having" when used in this
specification specify the presence of stated features, regions,
integers, steps, operations, elements, and/or components, but do
not preclude the presence or addition of one or more other
features, regions, integers, steps, operations, elements,
components, and/or groups thereof.
[0076] Furthermore, relative terms, such as "lower" or "bottom" and
"upper" or "top", may be used herein to describe one element's
relationship to another element as illustrated in the Figures. It
will be understood that relative terms are intended to encompass
different orientations of the device in addition to the orientation
depicted in the Figures. For example, if the device in one of the
figures is turned over, elements described as being on the "lower"
side of other elements would then be oriented on "upper" sides of
the other elements. The exemplary term "lower" can, therefore,
encompass both an orientation of "lower" and "upper", depending on
the particular orientation of the figure. Similarly, if the device
in one of the figures is turned over, elements described as "below"
or "beneath" other elements would then be oriented "above" the
other elements. The exemplary terms "below" or "beneath" can,
therefore, encompass both an orientation of above and below.
[0077] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. It will be further understood that terms, such
as those defined in commonly used dictionaries, should be
interpreted as having a meaning that is consistent with their
meaning in the context of the relevant art and the present
disclosure, and will not be interpreted in an idealized or overly
formal sense unless expressly so defined herein.
[0078] As used herein, "around", "about", "substantially" or
"approximately" shall generally mean within 20 percent, preferably
within 10 percent, and more preferably within 5 percent of a given
value or range. Numerical quantities given herein are approximate,
meaning that the term "around", "about", "substantially" or
"approximately" can be inferred if not expressly stated.
[0079] As used herein, the terms "comprise" or "comprising",
"include" or "including", "carry" or "carrying", "has/have" or
"having", "contain" or "containing", "involve" or "involving" and
the like are to be understood to be open-ended, i.e., to mean
including but not limited to.
[0080] As used herein, the term "infiltration" refers to a medical
condition where IV fluid leaks into surrounding tissues. Generally,
IV infiltration may be commonly caused by improper placement or
displacement of the IV catheter.
[0081] Patients with different injuries or diseases may require IV
volume resuscitation and/or and IV pharmacologic administration.
FIG. 1 shows patients in need of IV volume resuscitation according
to certain embodiments of the present invention. As discussed
above, malpositioning or misplacing of IV catheters may occur at
any time for different patients to cause IV infiltration, which may
be a major cause of morbidity and is difficult to detect. The
economic burden caused by IV failures are costly. For example, the
compartment syndrome and other medical symptoms resulted by IV
failures may generate cost which must be absorbed by the hospitals
and medical facilities. Further, patients and their family members
may bring malpractice suits against the hospitals and medical
professionals. It is estimated that over 50% of the medical
malpractice claims are due to IV infiltration or extravasation, in
comparison to other types of claims such as chemotherapy
(.about.20%) and IV contrast (.about.0.7%). Further, there is no
existing devices for ensuring proper IV catheter placement do not
exist. Therefore, a need for IV devices and methods to ensure
proper IV catheter placement is desired.
[0082] In certain embodiments, IV tubing may be coupled with
pressure sensors to measure the average line pressure of the IV
tubing. However, average line pressure is not an efficient
parameter for detecting IV infiltration prior to tissue damage.
FIG. 2A shows a chart of line pressure of an IV tubing with a pump
flow at 50 mL/hour according to certain embodiments of the present
invention. As shown in FIG. 2A, the average line pressure for a
functional IV with a pump flow at 50 mL/hour is about 20 mmHg. When
IV infiltration begins, the line pressure may go up to about 125
mmHg for a period of time. However, after about 30 minutes, the
average line pressure for the infiltrated IV may be stabilized at a
value of about 25 mmHg. At this point, detection of IV infiltration
will be late as tissue damages have already occurred. FIG. 2B shows
a result of IV infiltration for about 30 minutes according to
certain embodiments of the present invention.
[0083] Accordingly, aspects of the present invention relates to
systems and methods of monitoring intravascular placement of an IV
catheter and detecting IV infiltration or misplacement on a living
subject, which may include human beings and/or other animals, and
applications of the same. In certain embodiments, the systems and
methods may utilize a disposable IV tubing with independent or
integrated venous pressure sensors, and durable dongle for wireless
connectivity and pump interfacing. In certain embodiments, a
proprietary spectral waveform analysis may be performed for
confirming IV placement. The systems and methods may implement
rapid infiltration detection.
[0084] In one aspect, the present invention relates to an
intravenous (IV) system. In certain embodiments, the system
includes: an IV catheter, configured to be inserted into a vein of
a living subject; a fluid controlling device in fluid communication
with the IV catheter, configured to control fluid flow from a fluid
source to the IV catheter; at least one pressure sensor in fluid
communication with the IV catheter, configured to acquire, from the
vein of the living subject, peripheral venous signals; and a
processing device communicatively connected to the at least one
pressure sensor. The processing device is configured to: receive
the peripheral venous signals from the at least one pressure
sensor; perform a spectral analysis on the peripheral venous
signals to obtain a peripheral venous pressure frequency spectrum;
perform a statistical analysis on amplitudes of peaks of the
peripheral venous pressure frequency spectrum to determine an IV
line functionality of the IV catheter in real time, where the IV
line functionality of the IV catheter indicates IV infiltration
when amplitude decreases greater than a first threshold are
detected from the peaks of the peripheral venous pressure frequency
spectrum; and when the IV line functionality of the IV catheter
indicates IV infiltration, control the fluid controlling device to
stop the fluid flow from the fluid source to the IV catheter.
Alternatively, the processing device may be further configured to,
when the IV line functionality of the IV device is determined to
indicate IV infiltration, control the fluid controlling device to
reduce a flow rate of the fluid flow from the fluid source to the
IV catheter, or generate an alert message.
[0085] A further aspect of the present invention relates to a
method for monitoring an IV line functionality of an IV device,
which includes: acquiring, from an IV catheter, peripheral venous
signals, wherein the IV catheter is configured to be inserted in a
vein of the living subject; performing a spectral analysis on the
acquired peripheral venous signals to obtain a peripheral venous
pressure frequency spectrum; and performing a statistical analysis
on amplitudes of peaks of the peripheral venous pressure frequency
spectrum to determine the IV line functionality of the IV device in
real time.
[0086] FIG. 3A shows an IV system according to certain embodiments
of the present invention. As shown in FIG. 3A, the IV system 300
includes: an IV device 310 and a processing device 320. The
processing device 320 is communicatively connected to the IV device
310. In certain embodiments, the connection between the IV device
310 and the processing device 320 may be through a network, which
may be implemented by a wired connection or a wireless connection.
Examples of the network may include without being limited to, a
local area network (LAN), a wide area network (WAN), the Internet,
or any other types of network.
[0087] The IV device 310 is configured to acquire, from a vein of a
living subject 330, peripheral venous signals. In certain
embodiments, the living subject may be a human being, or may be
other animals. In one embodiment, the living subject may be a human
patient who is given fluid through the IV device 310.
[0088] FIGS. 3B and 3C shows IV devices according to certain
embodiments of the present invention. In certain embodiments, the
IV device 310 may include an IV catheter 312, a tubing 314, a port
device 316 and a fluid controlling device 318. In certain
embodiments, the IV device 310 may include at least one pressure
sensor (not shown). The IV catheter 312 is used to be inserted into
the vein of the living subject 330 such that fluid may be supplied
into the vein. The tubing 314 has a first end and an opposite,
second end, where the first end is connectable to a fluid source
(not shown) supplying the fluid, and the second end is connected to
the IV catheter 312. The port device 316 is in fluid communication
with the tubing 314, and located between the first and second ends
of the tubing 314. In one embodiment, the port device 316 may
include a T-piece or Y-piece connector. The fluid controlling
device 318 is in fluid communication with the tubing 314, located
between the first and second ends of the tubing 314 and configured
to have an on position and an off position to control the fluid
flow from the fluid source to the IV catheter 312. The at least one
pressure sensor may be in fluid communication with the tubing 314
through the port device 316, for obtaining the peripheral venous
signals by measuring fluid pressures in the port device 316. In
operation, when the fluid controlling device 318 is in the on
position, fluid flow in the tubing 314 is allowed to pass through
the fluid controlling device 318, such that the at least one
pressure sensor measures both a fluid pressure from the fluid
source and a distal venous pressure from the vein, and when the
fluid controlling device 318 is in the off position, no fluid flow
in the tubing 314 is allowed to pass through the fluid controlling
device 318, such that the at least one pressure sensor measures the
distal venous pressure from the vein only. In certain embodiments,
the fluid controlling device 318 may be manually or automatically
controllable. In one embodiment, the fluid controlling device 318
may include a stopcock. In another embodiment, the fluid
controlling device 318 includes an intravascular line occlusion
mechanism, which may be manual or automatic. In certain
embodiments, the at least one pressure sensor may include a
pressure transducer, such that the peripheral venous signals are
captured and recorded by the pressure transducer.
[0089] The processing device 320 is configured to: receive the
peripheral venous signals from the IV device 310; perform a
spectral analysis on the peripheral venous signals to obtain a
peripheral venous pressure frequency spectrum in order to determine
an IV line functionality of the IV device 310; and perform a
statistical analysis on amplitudes of peaks of the peripheral
venous pressure frequency spectrum to determine an IV line
functionality of the IV device 310 in real time. In certain
embodiments, the processing device 320 may be a computing device,
which may be a desktop computer, a laptop computer, a smartphone, a
tablet device, or any other computing devices with processors to
perform the processing functions. In certain embodiments, the
processor may be associated with a circuit board of data
acquisition and process. In one embodiment, the processing device
320 may further include a display device (not shown) in
communication with the processor for displaying the processed fluid
pressures, and the display device may include a graphic interface.
In certain embodiments, the spectral analysis may be a spectral
fast Fourier transform (FFT) analysis. In certain embodiments, the
spectral analysis may be other frequency and/or k-space
transformation analysis.
[0090] FIG. 4 shows a flowchart of a method for monitoring an IV
line functionality of an IV device according to certain embodiments
of the present invention. As shown in FIG. 4, at step S410, the IV
device 310 acquires the peripheral venous signals from the vein of
the living subject. At step S420, upon receiving the peripheral
venous signals from the IV device 310, the processing device 320
performs a spectral process and analysis, such as the spectral FFT
analysis, on the peripheral venous signal to obtain a peripheral
venous pressure frequency spectrum. At step S430, the processing
device 320 performs a statistical analysis on amplitudes of peaks
of the peripheral venous pressure frequency spectrum to determine
the blood volume status of the living subject in real time. At step
S440, the processing device 320 determines whether a significant
amplitude decrease of the peaks is detected. If so, at step S450,
the processing device 320 determines that IV infiltration occurs.
If not, at step S460, the processing device 320 determines that no
IV infiltration occurs (meaning that IV is functional).
[0091] Generally, peripheral venous pressure (PVP) is strongly
correlated with central venous pressure (CVP), also known as mean
venous pressure (MVP), which is the pressure of blood in the
thoracic vena cava, near the right atrium of the heart. FIG. 5
shows comparison of CVP and PVP according to certain embodiments of
the present invention.
[0092] FIG. 6 shows (A) a chart of the peripheral venous waveforms
and (B) the Fourier transformation of the signals according to
certain embodiments of the present invention. As discussed above,
line pressure sensing is insufficient for detecting venous access
placement. In other words, merely using pumps and pressure sensors
is not suitable to reliably detect IV infiltration. However, the IV
systems and method as disclosed above may be used to detect and
analyze the venous waveforms in order to efficiently monitor and
detect IV infiltration. This is mainly due to the low venous
signal-to-noise of the venous waveforms, which necessitates signal
conditioning and spectral methods for analysis.
[0093] FFT separates the signals into the contributing frequencies.
The amplitudes of the contributing frequencies in the signals can
then be plotted and evaluated. FIG. 7 shows the conversion from the
peripheral venous signals to the peripheral venous pressure
frequency spectrum according to certain embodiments of the present
invention. As shown in FIG. 7, an electrocardiogram (ECG) of 128
beats may be converted to T-wave alternans that can be evaluated
with a FFT.
[0094] In certain embodiments, the steps S410 and S420 as shown in
FIG. 4 may be performed continuously, such that at two different
time period, two sets of the peripheral venous pressure frequency
spectrums may be obtained. For example, for a time period from
T.sub.0 to T.sub.2, the time period may be divided into a first
time period from T.sub.0 to T.sub.1, and a second time period from
T.sub.1 to T.sub.2, and each of the first time period and the
second time period may be used to obtain a separate set of
peripheral venous pressure frequency spectrums. In certain
embodiments, the time period may be divided into more than two time
periods, and multiple sets of peripheral venous pressure frequency
spectrums may be obtained. In certain embodiments, the peripheral
venous pressure frequency spectrum obtained at an earlier time may
be used as a baseline peripheral venous pressure frequency
spectrum. Thus, the statistical analysis at step S430 may be
performed by obtaining a plurality of baseline peaks {B.sub.N-1}
from a lower frequency side on a baseline peripheral venous
pressure frequency spectrum, where N is a positive integer, and the
plurality of baseline peaks {B.sub.N-1} respectively corresponds to
a plurality of frequencies {F.sub.0, F.sub.1, . . . , F.sub.N},
such that B.sub.N-1 is a function of F.sub.N-1 satisfying
B.sub.N-1=B.sub.N-1 (F.sub.N-1), wherein F.sub.N is greater than
F.sub.N-1. In other words, the baseline peaks may include a first
baseline peak B.sub.0 corresponding to a first frequency F.sub.0, a
second baseline peak B.sub.1 corresponding to a second frequency
F.sub.1, a third baseline peak B.sub.2 corresponding to a third
frequency F.sub.2 . . . , and the second frequency F.sub.1 is
greater than the first frequency F.sub.0. Then, a plurality of
peaks {P.sub.N-1} may be obtained on the peripheral venous pressure
frequency spectrum currently obtained, where the plurality of peaks
{P.sub.N-1} correspond to the plurality of frequencies {F.sub.0,
F.sub.1, . . . , F.sub.N}, such that P.sub.N-1 is a function of
F.sub.N-1 satisfying P.sub.N-1=P.sub.N-1 (F.sub.N-1). For example,
the peaks may include a first peak P.sub.0 corresponding to the
first frequency F.sub.0, a second peak P.sub.1 corresponding to the
second frequency F.sub.1, a third peak P.sub.2 corresponding to the
third frequency F.sub.2 . . . . In certain embodiments, the number
of peaks on the peripheral venous pressure frequency spectrum
equals to the number of baseline peaks on the baseline peripheral
venous pressure frequency spectrum. In this way, the IV line
functionality of the IV device 310 may be determined in real time
by comparing the amplitudes of the peaks to that of the
corresponding baseline peaks, respectively.
[0095] In certain embodiments, the IV line functionality of the IV
catheter is determined to indicate IV infiltration when amplitude
decreases greater than a first threshold are detected from the
baseline peaks {B.sub.N-1} to the peaks {P.sub.N-1}. FIG. 8 shows
the peripheral venous pressure frequency spectrum of (A) a
functional IV and (B) an infiltrated IV according to certain
embodiments of the present invention. As shown in FIG. 8(A), when
IV performs functionally, the amplitudes of the peaks of the
peripheral venous pressure frequency spectrum do not show any
significant decrease. In comparison, when IV infiltration occurs,
as shown in FIG. 8(B), the amplitudes of the peaks of the
peripheral venous pressure frequency spectrum decrease
significantly. If the decrease reaches the first threshold, the
processing device 120 will determine that IV infiltration has
occurred in the living subject.
[0096] In certain embodiments, in addition to performing the
statistical analysis on the amplitudes of peaks of the peripheral
venous pressure frequency spectrum, the system and method may
further utilize other features, such as performing mathematical
operations or transformations to obtain power peaks of the
peripheral venous pressure frequency spectrum to perform the
statistical analysis. For example, the system and method may
perform a mathematical operation for squaring the magnitude of the
signal in order to obtain the power peaks of the peripheral venous
pressure frequency spectrum, and then use the power peaks to
conduct the statistical analysis.
[0097] In certain embodiments, when the IV line functionality of
the IV catheter is determined to indicate IV infiltration, the
processing device 320 may perform actions to avoid injuries that
may be caused by the IV infiltration, where the action may be
determined based on the nature of the IV therapy and the condition
of the patient. For example, the processing device 320 may control
the fluid controlling device 318 to stop the fluid flow from the
fluid source to the IV catheter 312. Alternatively, the processing
device 320 may control the fluid controlling device 318 to reduce a
flow rate of the fluid flow from the fluid source to the IV
catheter 312. In another example, the processing device 320 may
generate an alert message to notify the medical professionals about
the IV infiltration.
[0098] The inventors have utilized the systems and methods as
discussed above in different models as a plurality of examples,
including a human being model (n=6) for linear SSE analysis and a
porcine model (n=8) for spectral analysis, to analyze and study the
sensitivity and specificity of shifts in the peripheral venous
waveforms. The tests in the examples are performed in standardized
settings in order to test the hypothesis that the systems and
methods are is more sensitive and specific than standard and
invasive line pressure sensing of IV filtration.
[0099] FIG. 9A shows the ROC curves for detection of linear SSE
analysis on human beings according to certain embodiments of the
present invention. FIG. 9B shows a table of the ROC curves and 95%
confidence interval (CI) for the data as shown in FIG. 9A according
to certain embodiments of the present invention. As shown in FIGS.
9A and 9B, the ROC curve is generated with an area under the curve
(AUC) of 0.9184, the standard error is 0.07490, and the 95% CI is
from 0.7715 to 1.065.
[0100] FIG. 10A shows the ROC curves for spectral analysis on
porcines according to certain embodiments of the present invention.
FIG. 10B shows a table of the ROC curves and 95% confidence
interval (CI) for the data as shown in FIG. 10A according to
certain embodiments of the present invention. As shown in FIGS. 10A
and 10B, the ROC curve is generated with an area under the curve
(AUC) of 0.9688, the standard error is 0.03926, and the 95% CI is
from 0.8918 to 1.046.
[0101] In certain embodiment, the data undergoes the Fourier
transform and a physiologic signal associated with the same
frequency (e.g. heart rate) is used to determine proper line
placement.
[0102] The invention relates to systems and methods for monitoring
and detecting IV infiltration using peripheral venous pressure
analysis algorithm, t, and its applications. In certain aspects,
the invention recites, among other things: [0103] 1) Harmonic
peripheral venous pressure waveform analysis algorithm. [0104] 2)
Method of measuring peripheral venous pressure frequency spectra
for determination of real-time IV infiltration. [0105] 3) A venous
pressure monitor algorithm that can distinguish between functional
IV and infiltrated IV (which may be caused by IV malpositioning or
misplacement). [0106] 4) A closed loop system for controlling IV
fluid supply with a peripheral venous pressure monitor and
intravenous fluid pump.
[0107] The foregoing description of the exemplary embodiments of
the invention has been presented only for the purposes of
illustration and description and is not intended to be exhaustive
or to limit the invention to the precise forms disclosed. Many
modifications and variations are possible in light of the above
teaching.
[0108] The embodiments were chosen and described in order to
explain the principles of the invention and their practical
application so as to enable others skilled in the art to utilize
the invention and various embodiments and with various
modifications as are suited to the particular use contemplated.
Alternative embodiments will become apparent to those skilled in
the art to which the present invention pertains without departing
from its spirit and scope. Accordingly, the scope of the present
invention is defined by the appended claims rather than the
foregoing description and the exemplary embodiments described
therein.
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