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Description  |
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BACKGROUND OF THE INVENTION
1. Field of Invention
This invention relates to a electrocardiogram (ECG) diagnostic device, and
more specifically, to a disposable ECG diagnostic chest pad having
pre-positioned lead electrodes and internal wiring which may be placed
quickly as a single unit upon a patient and may be separated into two
sections by way of perforated sections in the underling pad material, thus
allowing greater flexibility in monitoring and diagnosing a patient's
electrocardiogram waves.
2. Description of Prior Art
It has been long known in the medical community that the current condition,
and possibly future state, of a subject patient's heart muscle can be
ascertained by measuring the cardiac electrical activity. The electrical
system of the heart not only initiates and controls the rate of heartbeat,
but also coordinate to transmission in the most efficient mechanical
manner. When such electric signals are irregular, it is a sign of cardiac
problems, particularly cardiac arrest, better known as a "heart attack."
Like all electrical signals, the electrical signals generated by the heart
can be expressed as a wave or a series of waves having a frequency and
amplitude. Again, like all electrical signals, these waves can be detected
and measured--in this case by an electrocardiograph. Electrodes, generally
pads containing conductive material, such as silver chloride and an
adhesive are attached to the trunk and limbs of a patient's body. The
electrodes are in turn attached to "leads" or cables which are connected
to the electrocardiograph. Generally, in modem medical practice a ten-lead
electrocardiograph is used to produce twelve lead measurements through the
use of bipolar electrodes. The electrocardiograph receives the signals
from the leads, processes them and outputs the resulting waveform
patterns, usually on a strip of moving paper. These resulting patterns are
known as an electrocardiogram (ECG). By viewing the resulting ECG output,
the physician or other healthcare professional can determine the current
condition of the patient's heart muscle and can compare such pattern
against healthy and known abnormal patterns. As such, an initial diagnosis
of the patient's condition can be made.
The majority of electrocardiological testing is performed in hospital
emergency rooms where time of patient treatment of the essence in order to
obtain a positive outcome. Trained personnel are required to properly
position the electrodes onto the chest wall and limbs of the patient and
connect the corresponding wires. In an emergency room situation, this
procedure must be performed with speed and accuracy. The work of attaching
the ten or twelve electrodes and the corresponding leads can be time
consuming. In addition, the leads tend to clutter up the chest area,
making additional emergency medical procedures more difficult to perform.
Such problems associated with this process are increased when the patient
is a small child or an infant.
Traditional prior art electrocardiograph systems typically utilize
electrodes comprising elastic cloth or other material having moderate
flexibility together with rigidity and strength, such as rubber, synthetic
rubber or porous synthetic resins having air permeability. Lead cables are
attached either externally or internally and are connected to a control
box mounted on the pad. The pad is fastened with belt- or strap-like
means, which must wrap around the subject's waist, chest, and arms. These
pads are generally used for long term monitoring, and are not typically
disposable. For the short-term use in the emergency room, single
disposable electrodes are individually applied, with an adhesive backing,
to the patient's body at the designated optimal locations. The
corresponding leads from the electrocardiograph are then attached to the
electrodes by any number of means known in the art, such as alligator
clips or plugs. As previously mentioned this process is cumbersome and
time consuming, particularly within an emergency situation. Under such
circumstances, the electrodes may be incorrectly placed or fall off the
patient, thus requiring additional time for replacement upon the patient.
Several solutions are presented in the prior art which attempt to solve
some of the aforementioned problems by pre-positioning the leads. The
first general solution seen in the art is a vest that contains the leads
built into the material. Two such examples are an "Apparatus for
Transmitting ECG Data," to Mills, U.S. Pat. No. 4,608,987 and an "ECG
Diagnostic Pad," to Sekine, U.S. Pat. No. 5,224,479. By having the leads
prepositioned within the vest, the entire apparatus can be placed upon the
patient and immediately used, thus saving valuable time. However, such
vests, including those seen in Mills and Sekine, have several drawbacks.
First, these vests must be made in multiple sizes in order to fit the vast
multitude of patient sizes and shapes from infant to adult and from thin
to overweight. Production and acquisition costs are increased as well as
the storage space needed to stock a supply of multiple, different-sized
vests. The amount of materials used for an entire vest also adds to cost
concerns. Most prior art vests are not disposable and reuse and
refurbishment costs may be prohibitive.
A second solution presented in the prior art is the use of "electrode
strips." In these devices, the electrodes placed within a strip of
material, usually containing an adhesive backing layer. The leads are
generally wired into the strip. When need, the adhesive backing is exposed
or adhesive otherwise applied and the strip is positioned and affixed to
the patient's torso. Representative examples can be see in U.S. Pat. No.
4,233,987 to Feingold, U.S. Pat. No. 5,184,620 to Cudahy et al. and U.S.
Pat. No. 5,868,671 to Mahoney. While cheaper to produce, store and use
than vests, these and other prior art strips do have their drawbacks.
First, may of the prior art electrode strips, such as the device
illustrated and claimed in the Cudahy et al. patent, utilize leads which
are positioned only across the torso of the patient. Readings from the
upper and lower extremities cannot be taken or optimal positioning cannot
be obtained. The Feingold strip allows individual placement, but having
only three leads, it is likely that the medical professional would not
utilize placement at the extremities. Another drawback to prior art
electrode strips is their inability to be used to monitor a patent. Often,
after the initial diagnosis, a physician or other medical professional may
wish merely to monitor the patient's cardiac activity. As such, only
certain leads of the ECG need to be used. It is, again, preferable, to
eliminate as leads and other materials from the patient's chest in order
to allow room for other procedures. Using the conventional technique of
placement of individual leads, the unnecessary leads can be removed.
However, in prior art electrode strips, one cannot remove the unnecessary
electrodes without also removing the electrodes needed for the monitoring
function.
It is therefore an object of the present invention to provide a means for
quickly and accurately positioning electrodes and leads for
electrocardiographic analysis.
It is a further object of the present invention to provide an
electrocardiographic electrode pad that provides signals from the torso
and extremities of a patient.
It is yet another object of the present invention to provide an
electrocardiographic electrode pad that can be used for patient
monitoring.
It is an additional object of the present invention is to provide
inexpensive and disposable ECG diagnostic pad which can be attached and
removed quickly so as to not interfere with other procedures such as chest
X-rays.
SUMMARY OF INVENTION
To attain the objects described above according to this invention, there is
provided an ECG diagnostic pad comprising a pad base with upper fit
portions with upper limb lead electrodes, a central fit portion with
unipolar precordial lead electrodes and a lower portion with flank lead
electrodes. The corresponding electrode wires, connecting the pad to the
monitoring unit, are embedded in the pad internally to eliminate clutter
and time of attaching them to the electrodes. The pad is attached with an
adhesive, which is on the backside of the pad eliminating the need for
belts or straps. By attaching the pad to the chest wall of a human subject
or patient, all of the pre-wired electrode leads come in contact with the
proper locations simultaneously, allowing rapid connection to the ECG
monitor in a one-step process.
In the most preferred embodiment, the inventive ECG electrode pad contains
a perforation between leads V1 and V2 which would allow the easy removal
of leads V2-V6, when monitoring is required without the need for a full
twelve lead ECG. Leads V2-V6 can be easily applied separately if the
patent requires a full twelve lead ECG later.
This and other features, aspects and advantages of the present invention
will appear and become better understood from the following description in
which the preferred embodiments are set forth in detail in conjunction
with the appended claims and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Specific embodiments of the invention have been chosen for purposes of
illustration and description, and are shown in the accompanying drawing,
forming a part of the specification wherein:
FIG. 1 is a perspective view of a human subject fitted with one embodiment
of the emergency ECG electrode pad according to the present invention;
FIG. 2 is a top of the pad in FIG. 1;
FIG. 3 is a bottom view (patient contact side) of the pad in FIG. 1;
FIG. 4 is a sectional view of a representative lead electrode used in one
embodiment of the present invention;
FIG. 5 is a top view of another embodiment of the subject invention with
external pacer pads;
FIG. 6 is a bottom view (patient contact side) of the pad in FIG. 5;
FIG. 7 is a top view of another embodiment of the subject invention with
defibrillation pads;
FIG. 8 is a bottom view (patient contact side) of the pad in FIG. 7.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, the preferred embodiment of the ECG electrode chest
pad 10 according to this invention is shown. The base ECG electrode chest
pad 10 is generally comprised of a medial portion 12, upper fit portions
14 and lower fit portions 16 such that the entire pad forms the general
shape of an elongated "X" with an additional line extending from the
center to the right, to reduce the surface area of the invention. As is
shown in FIG. 1, the pad 10 is placed upon the patient 20 such the upper
fit portions 14 extend aslant upward and are generally at the patient's
shoulders and that the medial portion 12 extends generally down the
patient's sternum and to the left across the chest wall, below the heart.
The lower fit portions 16 extend aslant downward and should therefore be
around the lower abdomen of the patient 20. In order to accommodate
patients of various sizes, it is contemplated that invention would be
manufactured in at least five different sizes: infant, small, medium,
large, and extra large.
The chest pad 10 is preferably made of a flexible, breathable or porous
material known in the art, such as cotton, polyester or, most preferably,
foam. The material, preferably is also radiologically transparent to
x-rays and other diagnostic procedures, such as ultrasound and magnetic
resonance imaging (MRI). An adhesive is applied reverse side of the pad
10. (shown in FIG. 3). Any temporary medical adhesive known in the art may
be used with the instant invention so long as it does not distract from
the function of the pad 10 or patient comfort. The adhesive preferably is
applied to the entire back surface of the pad 10 and covered with a
backing (not shown) until needed. In the alternative, the adhesive can be
applied to several contact points across the back of the pad 10 during
manufacture and covered with a backing until use or, less preferably, the
adhesive is applied just prior to use.
A more detailed close-up of the ECG electrode pad 10 is shown in FIG. 2. As
can be seen, the pad 10 contains a series of electrodes 30-34 that are in
turn electrically connected to two wiring harnesses 36 and 38. The medial
portion 12 contains six unipolar precordial lead electrodes 30a (V1), 30b
(V2), 30c (V3), 30d (V4), 30e (V5) and 30f (V6) which contact the patient
20 from the midriff to the flank. The upper fit portions 14 contain a
right-limb electrode 32a and a left-limb electrode 32b for detecting
bipolar and unipolar ECG currents. Accordingly, the lower fit portions 16
contain a right-flank electrode 34a and a left-flank electrode 34b that
detect bipolar and unipolar ECG currents. The reverse side of FIG. 2 is
shown in FIG. 3. In this view, an adhesive 40 is applied to the entire
surface of the pad 10, per one embodiment of this invention. When the pad
10 is applied to the patient 20 chest all three portions, 10, 12, and 14
and their respective electrodes 30-34 simultaneously come in contact with
the patient.
Each of the electrodes are electrically attached to leads or wires 50.
These leads 50 are placed within the material of the ECG pad 10 and are
thus integral thereto. The leads 50, in turn, terminate and form two lead
bundles 36 and 38. The leads 50 of electrodes 32a-b, 34a-b and 30a form
the lower lead bundle 38 while the upper bundle 36 is formed from the
leads 50 of electrodes 30b-f. Both bundles 36 and 38 terminate with plugs
52 that are adapted to quickly and easily plug into an ECG monitor 60 to
relay signals from the electrodes. Because the electrodes are pre-wired,
by coupling the plugs 36 and 38 with the ECG monitor 60, the patient would
ready for an electrocardiograph diagnosis without having to make
repetitive connections for each lead 50. In addition, the clutter of
external wires is eliminated. As shown particularly in FIGS. 1-3 both
bundles are located in the center or medial portion 12 of pad 10. It is
also contemplated that for better ease of use and separation of the pad 10
into two portions as detailed herein, bundle 38, and the wires 50
associated therewith, would terminate in the lower fit portion 16, towards
lead 34b.
FIG. 4 illustrates a cross-section of an typical electrode in the subject
invention Each lead electrodes, such as electrode 30a, is comprised of a
casing 60, containing Ag/AgCl solid conductor gel 62, which is mounted in
the pad 10. The Ag/AgCl solid conductor gel 62 is exposed on the backside
of the pad 10 to ensure contact with the chest wall. Embedded in the
center of the Ag/AgCl solid conductor gel 62 is a solid metal stud 64.
Stud 64 can be made of any conductive metal or alloy known in the art. It
is contemplated that inventive ECG pad can also utilize other types of
electrodes now used in the art or later discovered, that may or may not
use metal studs and/or conductive gel, so long as an appropriate signal is
delivered from the patient to the ECG monitor 60.
Referring again to FIGS. 2 and 3, an important feature of the most
preferred embodiment of the subject invention is illustrated. The material
of pad 10 contains a perforation 70 which runs from the upper fit portion
14 containing electrode 32b (left-flank), between electrodes 30a (V1) and
30b (V2) and underneath electrodes 30c-30f (V3-6). This feature allows
removal before or during application of the ECG pad 10 of leads 30b-30f
(V2-V6). In certain circumstances, the physician or other health care
profession may merely wish to monitor the patient without the need for a
full twelve lead ECG. In general, electrodes 30b-30f and attached leads 50
are not needed for monitoring. In addition, the space otherwise taken up
on the patient's chest with these leads may be needed for another medical
procedure or instrument. The use of perforation 70 allows an easy one-step
removal of these leads. Leads 30b-30f (V2-V6) can be easily applied
separately if the patent requires a full twelve lead ECG later.
FIGS. 5 and 6 illustrate a second embodiment of the subject invention. In
addition to the structures and features detailed in the preferred
embodiment, it is contemplated that external pacer pads 100a and 100b can
be added to the device. The external pacer pad 100a is located just below
the right upper fit portion 14 of the pad 10 and external pacer pad 100b
is located just below the horizontal central fit portion 12, which are the
proper positions for the prescribed anatomical locations. Like an
implanted pacemaker, pacer pads 100 and 100 serve to provide an electrical
pulse to the heart to correct an irregular heartbeat. Pacer pads 100a and
100b are electrically connected to pacer control instrument 110 by way of
wires 102a and 102b that form a pacer plug bundle 104. Although wires 102a
and 102b can be embedded in the fabric of pad 10, the are preferably left
free or retained to the exterior of the pad 10 by the minimal use of an
adhesive such that the wires 102a-b can easily be moved or removed with
the pacer pads 100a-b, as further described herein. Like the electrode
plug bundles 36 and 38, the pacer plug bundle 104 can quickly be attached
and detracted to the pacer control instrument 110. The control instrument
110, alone or in conjunction with the ECG monitor 60, can measure and
monitor the patient's heartbeat and if irregular can administer a
corrective electric pulse to the patient by way of the pacer pads 100a and
100b. A perforation 70 can also be incorporated into this embodiment such
that electrodes 30b-30f (V2-V6) can be removed, as previously described in
the primary embodiment of the inventive ECG pad. Conversely, the portion
of the medial pad portion 12 containing electrodes 30a, 32a, 32b, 34a, and
34b and the pacer pads 100a and 100b can be retained on the patient, thus
allowing continued pacing. One additional variation of this embodiment
results from the use of additional perforations in the pad 10 in lieu of
or in addition to perforation 70 which allow separation of all of the
electrodes 30a-f, 32a-b, and 34a-b, thus removing the pacer pads 100a and
100b and wires 102a and 102b from the patient and leaving electrodes
30a-f, 32a-b and 34a-b attached to the patient. In the alternative, pacer
pads 100a and 100b and wires 102a and 102b can be left on the patient and
electrodes 30a-f, 32a-b and 34a-b removed.
A third embodiment of the invention is illustrated with reference to FIGS.
7 and 8. In addition to the structures and features detailed in the
preferred embodiment, it is contemplated that defibrillator pads 200a and
200b properly positioned for the prescribed anatomical locations can be
added to the ECG electrode pad 10. The defibrillator pad 200a is located
just below the right upper fit portion 14 of the pad 10 and defibrillator
pad 200b is located just below the horizontal central fit 12 portion of
the pad 10. The defibrillator pads 200a and 200b are made of a flexible
solid conductor gel to ensure contact with the patent and can be adhered
to the patient as know in the art, consistent with the techniques used for
the main ECG pad 10. If defibrillation of the patient is required, the
physician can applied the defibrillation paddles of the defibrillator
directly to pads 200a and 200b without use of separate conductor gel. As
previously described in the primary embodiment of the inventive ECG pad, a
perforation 70 can also be incorporated into this embodiment such that
electrodes 30b-30f (V2-V6) can be removed. Conversely, the portion of the
medial pad portion 12 containing electrodes 30a, 32a, 32b, 34a, and 34b
and the defibrillator pads 200a and 200b can be retained on the patent,
thus allowing continued defibrillation of the patient. Perforations 202
can also be formed between the defibrillator pads 200a and 200b and the
medial pad portion 12, to allow removal of the defibrillator pads 200a and
200b from medial pad 12.
In addition to the uses immediately described above, it will be apparent to
those skilled in the art that other modifications and variations can be
made the method of the instant invention without diverging from the scope,
spirit, or teaching of the invention. Therefore, it is the intention of
the inventors that the description of instant invention should be
considered illustrative and the invention is to be limited only as
specified in the claims and equivalents thereto.
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