U.S. patent number 3,895,635 [Application Number 05/371,773] was granted by the patent office on 1975-07-22 for electrosurgical grounding cable assembly.
This patent grant is currently assigned to NDM Corporation. Invention is credited to George Junior Justus, Lowell C. Miller, Charles T. Patrick, Jr..
United States Patent |
3,895,635 |
Justus , et al. |
July 22, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
Electrosurgical grounding cable assembly
Abstract
A connector for the grounding cable of an electrosurgical
generator (E.G.) has a non-conductive body carrying an electrical
contact plate against which a stud of an indifferent electrode in
an electrosurgical grounding pad is locked by a non-conductive cam
lever pivotally mounted on the body portion. The body has one end
of the grounding cable located therein in attachment to the contact
plate with the other end of the grounding cable having a terminal
plug for insertion in a socket of the electrosurgical generator. As
an adjuvant feature, the body has a receptacle engaged with the
contact plate and adapted to receive a pin jack on a grounding wire
for interconnecting a monitoring patient cable ground circuit of an
electrocardiograph machine (E.K.G.) and the electrosurgical patient
grounding cable.
Inventors: |
Justus; George Junior (York
Haven, PA), Miller; Lowell C. (Lewisburg, OH), Patrick,
Jr.; Charles T. (Centerville, OH) |
Assignee: |
NDM Corporation (Dayton,
OH)
|
Family
ID: |
23465353 |
Appl.
No.: |
05/371,773 |
Filed: |
June 20, 1973 |
Current U.S.
Class: |
606/32; 439/147;
439/447; 439/909; 439/140; 439/299; 439/374; 439/864; 606/35 |
Current CPC
Class: |
A61B
18/16 (20130101); A61B 5/276 (20210101); A61B
5/303 (20210101); A61N 1/04 (20130101); Y10S
439/909 (20130101) |
Current International
Class: |
A61B
18/16 (20060101); A61B 18/14 (20060101); A61B
5/0408 (20060101); A61B 5/0428 (20060101); A61B
5/0402 (20060101); A61B 5/0424 (20060101); A61N
1/04 (20060101); A61n 001/04 () |
Field of
Search: |
;128/2.6E,2.1E,303.13,303.14,303.17,303.18,404,416,417,418,415,414,413,412
;339/39,42,65,79,101,273F,274 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kamm; William E.
Attorney, Agent or Firm: Irons & Sears
Claims
What is claimed is:
1. For use with electrosurgical equipment including (a) an
electrosurgical generator for generating high frequency electric
current, (b) an active electrode electrically connected to said
generator and used to cut tissue and coagulate blood, and (c) an
indifferent electrode for attaching to a patient an electrical
ground means, a grounding assembly suitable for said
electrosurgical equipment and comprising, in combination, a
connector and a cable, said connector, in turn, comprising a body
provided with a slot defining an open trackway along a face of said
body for receiving, on one end of the trackway, a conductor
electrically coupled to said indifferent electrode, and means at
the opposite end of the trackway for terminating the trackway while
still retaining said conductor on said trackway, an electrically
conductive contact means, carried by said body, electrically
coupled with said conductor on said trackway, while said conductor
is in said trackway, and with one end of the cable, the opposite
end of said cable being electrically coupled to ground, and locking
means carried by said connector and positionable in said trackway
to lock said conductor in electrical contact with said contact
means.
2. The invention of claim 1, wherein said connector has a
non-conductive solid body.
3. The invention of claim 2, wherein said conductor electrically
coupled to said indifferent electrode is a projecting stud over
which the trackway slides and said stud is formed with a groove in
which the trackway moves.
4. The invention of claim 3 wherein said contact means includes a
resilient tab of conductive material arranged generally
perpendicularly of the trackway and providing said means at one end
of the trackway to terminate travel of the latter along the
conductor.
5. The invention of claim 4, wherein said locking means includes a
lever formed from non-conductive material, a pivot pin arranged
transversely of the trackway adjacent the open end thereof, said
lever having one end mounted on the pivot pin for swinging movement
about an axis normal to the trackway and said lever having an
opposing free end portion having a cam surface releasably engaging
the stud in clamping relation with the tab.
6. The invention of claim 5, wherein said connector body has
opposing top and bottom faces, said opening of said trackway being
in said bottom face of said body, said contact means including a
plate portion fixed on the bottom face and from which the tab
upstands in the trackway, said connector body having opposing ends
and the trackway being elongated and passing through one end of the
body and said pivot pin being disposed and passing through one end
of the body and said pivot being disposed at said end.
7. The invention of claim 6, wherein said plate portion is
longitudinally split to effect two plate sections and the resilient
contact tab upstands in the trackway from one of said sections and
arrests the inward movement of the stud along the trackway.
8. The invention of claim 7 wherein said top face of the connector
body has a depression of a size and shape approximating the size
and shape of the lever which is seated therein, said depression, in
turn, having an opening in the bottom thereof in communication with
said trackway having said stud upstanding therein, the opening
being of a size and shape approximating the size and shape of the
cam surface releasably engaging the stud in clamping relation with
said tab, and said pivot pin is in a plane above the plane of the
bottom of the depression with said lever being disposed below the
pivot pin plane when it is seated in the depression so that it is
below its pivot axis and is locked in place in the depression.
9. The invention of claim 8 wherein said locking lever has an
angular lip on its free end, said lip projecting upwardly from the
lever in its seated and locked position and defining a finger
piece.
10. The invention of claim 9 wherein said connector body is
transparent.
11. The invention of claim 9 wherein said cable whose proximal end
is attached to said connector comprises lead wire encased in
transparent plastic for visual inspection of the lead wire, and, at
the distal end of the cable, a transparent terminal plug for visual
inspection of the contact means by which the distal end of said
lead wire is attached.
12. The invention of claim 1 wherein said electrosurgical equipment
includes an electrocardiograph machine having a monitoring patient
cable ground circuit and said connector is provided with a
receptacle in contact with the contact means, a grounding wire
having opposing jack plug ends, one of said jack plug ends being
attached to the ground jack of the electrocardiograph machine and
the other jack plug end being insertable in the receptacle in the
connector body.
13. A cable grounding assembly for use with an electrosurgical
grounding pad having a patient contacting inner surface and an
outer surface from which a stud projects having an annular groove,
said assembly comprising a connector having a solid non-conductive
body portion having opposing top and bottom faces, and formed in
the bottom of said faces is a slot-like, elongated trackway which
slides over the stud and in the groove, said trackway having an
outer end and an at least partially closed inner end, an
electrically conductive contact plate fixed to the bottom face and
having an integral inherently resilient tab projecting therefrom
and disposed in the trackway at the inner end thereof and which
bears against the stud, a locking lever of non-conductive material
pivotally mounted on the connector body adjacent the outer end and
means for locking the lever in clamping relation with the stud so
as to lock the latter against the contact tab to prevent motions
transverse to and parallel to said trackway and a grounding cable
extending from the connector body in contact with the contact plate
and having a distal end provided with a terminal plug adapted to be
inserted in an electrosurgical unit.
14. The invention of claim 13 wherein said locking means includes
said top face of the connector body being formed with a depression
of a size and shape to receive the lever and a pivot pin for the
lever arranged in the connector body transversely of the trackway
at the open end thereof and disposed in a plane above the bottom of
the depression so that the major part of the lever is below the
pivot axis when seated in the depression.
15. The invention of claim 14, wherein said lever has a free end
provided with an angular lip that upstands therefrom when the lever
is seated in the depression and extends above the top face of the
connector body.
16. The invention of claim 13, wherein said connector body,
grounding cable and terminal plug are transparent.
17. The invention of claim 16 wherein the connector body, the cable
and the terminal are formed from transparent polymeric
materials.
18. A grounding assembly suitable for use with electrosurgical
equipment and comprising, in combination, a connector and a cable,
said connector, in turn, comprising a body provided with a slot
defining an open trackway along a face of said body for receiving
on one open end of the trackway, a conductor and means at the
opposite end of the trackway for terminating the trackway while
still retaining said conductor on said trackway, an electrically
conductive contact means, carried by said body, electrically
coupled with said conductor on said trackway, while said conductor
is in said trackway, and with one end of the cable, the opposite
end of said cable being electrically coupled to ground, and locking
means carried by said connector and positionable in said trackway
to lock said conductor in electrical contact with said contact
means.
19. The invention of claim 18 wherein said conductor is a stud
having an annular groove in which the trackway slides.
20. The invention of claim 18 wherein said connector body has a
bottom face and a top face and said contact means further includes
a thin plate fixedly superimposed on the bottom face and having a
trackway complementing the body trackway but of slightly less width
than the body trackway so that the bounding walls of the contact
plate trackway engage the conductor.
21. The invention of claim 18 wherein said connector body has a top
face formed with a surface cavity and said locking means includes a
locking lever, a pivot pin mounted in the connector body adjacent
the open end of the trackway and arranged transversely thereof,
said lever having one end pivoted on said pin and having a cam
means on its other end releasably engaging the conductor, with said
lever being sealed in the cavity and bearing against the conductor.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally appertains to new and novel
improvements in electrical connectors and is particularly directed
to new and novel electrosurgical grounding cable arrangement
whereby an indifferent electrode of an electrosurgical generator is
connected to the ground terminal of such generator.
2. Description of the Prior Art
In electrosurgical procedures, an electrosurgical generator (E.G.)
generates high frequency electric current which is fed to an active
electrode used to cut tissue and coagulate blood vessels. An
indifferent electrode is disposed in contact with the patient to
provide a return path of the short-wave current to the E.G. which
is in turn connected direct to ground or to an isolated ground
unit.
The input current is applied to the tissue by means of the active
electrode which is preferably of rather small cross-section so as
to obtain high current densities at the surgical site. These high
current densities provide the desired heating effect needed for the
operating procedure. However, it is essential that the indifferent
electrode be in such contact with the surface area of the tissue
that the return current has a low density, thereby avoiding burning
or scarring of the tissue in contact with the indifferent
electrode. If the indifferent electrode or its connection to the
current source is broken or faulty, the low current density is not
achieved and the tissue at the point where a high current leaves
will be burned or scarred.
Various factors can produce a faulty ground circuit. But one of the
most common causes of faulty grounding is an improper connection of
the ground wire.
In some instances, the grounding cable has a male terminal which
fits into a socket on a sizeable lead plate used as the indifferent
electrode and is fastened thereto by a thumbscrew. The danger in
this form of contact is that the terminal of the cable may become
detached from the terminal of the plate and the male end on the
terminal of the cable, should it touch the patient's skin, could
concentrate the whole of the current. This would produce a
thermoelectrical burn.
To avoid this, the lead plate terminal in some installations is a
male contact which fits into an insulated socket on the cable
terminal. If such cable becomes detached from the lead plate, there
would be no current flow from the plate to ground. The difficulty
with such terminal connections is obvious. If this faulty situation
occurs and the electrosurgical unit (E.G.) continues to generate
current, there is a high possibility of patient burns, since
current will seek another path to ground.
In other installations, the ground cable is permanently affixed, as
by welding, to the indifferent electrode plate. In such permanent
type installation, wear damage to the cable at its point of
attachment occurs, and repairing of the cable is very
difficult.
In any event, in known installations interrupted ground circuits
due to disconnection or improper structural association of the
ground cable and the indifferent electrode can occur. And such can
take place at crucial times in a given surgical procedure so as to
expose the patient to tissue damage and pain. And even if the
patient experiences no pain or damage, nonetheless valuable
operating time may be lost in effecting a repair of the ground
connection. Such lost time may be critical to the electrosurgery
procedure, even to the point of affecting the outcome thereof and
placing the life of the patient in jeopardy.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide an
electrosurgical grounding cable arrangement which obviates the
drawbacks attendant with known manners of attaching ground cables
to conventional patient ground plates.
The electrosurgical grounding cable arrangement of the present
invention has been designed to provide the utmost in patient safety
during electrosurgical procedures and is utilized with an
electrosurgical grounding pad of the type and nature disclosed in
U.S. applications Ser. Nos. 223,107, filed Feb. 3, 1972, now
abandoned, and 328,120, filed Jan. 30. 1973, both of said
applications being hereby incorporated herein by reference.
The electrosurgical grounding pad, as described in such
applications, comprises an electrolyte/electrode assembly wherein
the electrode and electrolyte are attached by an electrically
conductive snap fastener.
The snap fastener has a stud portion that terminates in an enlarged
head portion on its projecting distal end at the outer surface of
the pad. The terminal head portion provides an annular shoulder on
its underside.
The connector of the present invention includes an electrically
conductive contact plate which is mounted on one face of a
non-conductive body portion, the latter being preferably
transparent so as to allow visual inspection of the contact plate
and the contact points for the wiring. The body portion and the
contact plate are provided with coinciding elongated trackways
which slidably receive the shank of the stud. The contact plate is
provided with an integrally formed tab which is disposed
perpendicularly within the confines of the trackway at the terminal
inner end thereof and against which the stud abuts in its fully
captive position within the trackway. The tab is inherently
resilient, since the contact plate is formed from thin metallic
sheet material or similar electrically conductive material.
A locking lever is pivotally carried by the body portion which has
a depression or cavity of an outline approximating the geometrical
shape and size of the lever formed in the face opposite to the
contact plate. The locking lever is pivoted on a pin arranged
transversely of the trackway at the outer end thereof. The lever
carries on its underside a cam that engages the stud at a point
radially opposed to the tab. In the fully depressed position of the
locking lever wherein it is seated in the depression in the body
portion and lockingly positioned therein, the stud is securely
locked between the cam and the tab. In this manner, the connector
is positively locked onto the terminal stud of the indifferent
electrode.
The grounding cable is preferably a double lead wire encased within
a transparent and flexible sheathing formed from thermosetting or
thermoplastic polymers and copolymers including nylons,
polystyrene, polyvinyl chloride, acrylic resins, polyethylene,
polypropylene, polyvinylidene, chloride, and other like insulating
and/or engineering plastics.
According to one embodiment, the distal end of the grounding cable
has a single pin jack plug provided with two spaced contact points.
One of the wires is attached to one of the contact points and the
other wire is attached to the other contact point. When the
terminal plug is inserted in the proper receptacle of the
electrosurgical generator unit or diathermy machine, one of the
contacts will be connected to the ground terminal of the machine
while the other contact will be connected to a conventional
monitoring system build into the machine. Such monitoring system
monitors the continuity of the cable and its attachment to the
indifferent electrode. In the absence of good and proper contact or
cable continuity the monitoring system will activate an alarm means
and/or deactivate the electrosurgical unit.
Of course, the present invention encompasses the use of a single
wire cable to ground and no monitoring system. According to a
preferred embodiment, the contact plate is longitudinally split or
spaced apart at its terminal end forming essentially two plates or
longitudinal sections only one of which carries the aforedescribed
integrally formed tab. Being spaced apart, the sections are in
electrical continuity only when the stud portion of the snap
fastener is interposed as aforedescribed. In this embodiment, one
wire of a double wire cable is attached at its proximal end to one
section and the other wire, also at its proximal end, to the other
section. Thus, the fastener stud and head complete the circuit, one
wire leading to ground and the other wire leading to the monitoring
system. Again, in the absence of good and proper contact between
the plate and the fastener, or in the absence of cable continuity,
the monitoring system will activate an alarm means and/or
deactivate the electrosurgical unit.
Alternatively, the inner end of the contact plate may be closed
forming a single essentially U-shaped plate having a tab portion,
which plate may be used with one or two wires attached thereto.
When, as described above, two wires are separately attached to this
plate, one to ground and one to the monitoring system, only a
faulty cable wire would be monitored, since the inner end of the
plate completes the circuit and separation of the fastener from the
plate would not be monitored.
During electrosurgical procedures, it is common to have the patient
monitored by a conventional electrocardiogram machine which records
the nature of the rhythmic change of certain electrical
characteristics of the body which are synchronous with the
heartbeat. In this way, different aspects of the phenomenon of
heart action and circulation of blood in the patient are
continually observed.
As an adjuvant feature of the present invention, the connector has
its body portion formed with a pin jack receptacle which is
attached to the contact plate alongside and along with the ends of
the wires of the grounding cable. Such contact points are
rearwardly of the inner end of the trackway. A terminal jack on a
grounding wire is adapted to be socketed in the receptacle with the
other end of the wire having a terminal jack that is inserted into
the ground lead of the electrocardiogram cable.
In such fashion, the patient is hooked onto two grounds, one being
the ground terminal of the diathermy machine or electrosurgical
unit and the other being the ground circuit of the
electrocardiogram machine. In this way, the safety of the patient
is much enhanced during electrosurgical procedures. By utilizing
the cable connector as a site for connecting the electrocardiogram
ground lead, potential grounding hazards possible through the
conventional EKG electrode should failure occur in the ground
system of the electrosurgical unit are eliminated. Further, the use
of the cable connector ground receptacle, instead of the typical
EKG ground electrode connector, results in a reduction of monitor
interference when the electrosurgical unit is in a stand-by
position. The net result is a better recording of the
heartbeat.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partly pictorial, partly schematic diagram illustrating
the electrosurgical grounding cable assembly of the present
invention in operative association with an electrosurgical
grounding pad and depicting the same in use with a patient and in
connective association with an electrosurgical unit and an
electrocardiograph machine.
FIG. 2 is a perspective showing of the grounding cable assembly and
the electrosurgical grounding pad is an unattached relation.
FIG. 3 is a perspective view of the grounding cable assembly in
attachment to the grounding pad on the skin surface of a
patient.
FIG. 4 is a longitudinal vertical sectional view of the connector
attached to the electrode of the grounding pad and showing the
locking mechanism in a full line down or locked position and in a
dotted line open or unlocked position and is taken substantially on
line 4--4 of FIG. 3.
FIG. 5 is a longitudinal horizontal sectional view taken
substantially on line 5--5 of FIG. 4 and showing the connector in
bottom plan.
FIG. 5A is a bottom plan view of a modified form of connector
wherein the contact plate is longitudinally split into two separate
longitudinal sections.
FIG. 6 is a transverse vertical sectional view, taken substantially
on line 6--6 of FIG. 4.
FIGS. 7 and 8 are fragmentary sectional views showing the locking
lever in its open and closed position with respect to the
protruding stud on the electrosurgical grounding pad.
Referring now more particularly to the accompanying drawings and
initially to FIGS. 2 and 4 for a general understanding of the
electrosurgical grounding pad assembly, which is more fully
disclosed in the aforementioned patent applications, the pad 10 is
composed of a substantially rectangular flexible and resilient
sheet 12 carrying a substantially centrally located non-conductive
cup member 14. The cup member has a flat base 16 superimposed on
one side or face of the sheet. And the cup member has a cavity 18
opening to the body surface of the patient. Within the cavity and
resting on the interior surface of the base 16 is a flexible sheet
20 of conductive metal electrode. The diameter of the cup member 14
is substantially greater than its height, thus providing a low
profile.
The flexible and resilient sheet 12, the cup member 14 and the
flexible sheet 20 of conductive metal are held together by an
electrically conductive stud fastener 22. The fastener includes an
inner annular plate 24 from the center of which a hollow shank 26
projects outwardly and an outer plate 28 having a hollow socket
portion 30 receiving the shank 26.
The parts are assembled and held together by centrally locating and
aligning the cup member 14 containing the likewise centrally
located and aligned flexible sheet 20 of conductive metal and the
outer plate 28 with its hollow socket portion 30 on opposite sides
of the sheet 12. The shank 26 is inserted through aligned apertures
in the centers of the flexible conductive sheet 20, the base 16 and
the resilient sheet 12 and is socketed in the socket 30. By
pressing together such portions of the stud, the upper part of the
stud 22 is crimped inwardly and its side walls collapse outwardly
whereupon the parts are tightly wedged together. In so doing, the
stud, composed of the sheet portion 30 and the shank 26, is formed
with an outer rounded and enlarged head or distal end portion 32
that, due to its enlargement in relation to the shank port of the
stud, has an annular groove 34 (cf. FIG. 7) formed below the distal
end and defining an annular locking shoulder 33.
The electrolyte is preassembled with the electrode 10 by soaking a
disc-shaped sponge-like cellular matrix 35 of non-conductive,
open-cell material with an electrode jelly. The sponge-like matrix
35 preferably has a diameter equal to the diameter of the base 16
of the cup member 14 and a thickness greater than the depth of the
cup member 14, as can be appreciated from a consideration of FIG.
4. It is sufficiently heavily laden with electrode jelly that, when
the electrode 10 is pressed on the skin surface of the patient, the
jelly fills the entire volume of the cavity between the skin
surface and the conductive metal sheet 20 and plate portion 28
whereupon good electrical contact between the skin and the
conductive metal sheet electrode 20 and the connective stud 22 is
assured.
As diagrammatically and pictorially depicted in FIG. 1, the
electrosurgical grounding pad 10 is applied on the arm of the
patient P and, because of the nature of the pad, it is easily
contoured to the curved skin surface. Obviously, the pad can be
applied to the patient in any area selected by the surgeon. But it
is preferred that the area be a curved skin surface, such as a
thigh or arm easily accessible for attachment of the
electrosurgical grounding cable assembly 36, as shown in FIG. 1.
The pad is applied by pulling it taut just as in the manner of
applying a bandage.
The electrosurgical grounding cable assembly 36 is generally
composed of a connector 38 which is lockingly attached to the head
portion 32 of the stud 22 by being slidably engaged within the
groove 34, as shown in FIG. 4. The connector 38 has one end of a
cable 40 attached thereto, as will be described, so as to be in
electrically conductive relation with the stud 22 and thereby with
the indifferent electrode 20. The grounding cable 40 is composed of
two lead wires 42 and 44 that are housed in a transparent
insulative sheathing or covering 46. The sheathing or covering 46
is flexible and preferably transparent so that a quick visual
inspection can be made for any breakage or damage of the lead wires
42 and 44 housed therein. The sheathing is formed from
non-conductive transparent materials, such as thermosetting or
thermoplastic polymers and copolymers of various types, e.g.,
polyethylene, polypropylene, or like insulating plastics.
The grounding cable 36 terminates in a single pin jack plug 48
which also has a non-conductive body portion of, preferably,
transparent material. The plug and the body portion 50 of the
connector are solid and may be molded or otherwise formed from
thermosetting or thermoplastic polymers and copolymers including
nylons; polyethers, such as oxymethylene polymers and copolymers;
polystyrene; ABS; polyvinyl chloride; polymethacrylate;
polymethylmethacrylate and polyacrylonitrile, copolymers thereof
and other like acrylic resins; polyethylene; polypropylene;
polyvinylidene chloride; polysulfones; polycarbonates; and other
like insulating and engineering plastics.
The electrosurgical generator or unit 52 has an active electrode 54
which is connected by a lead 56 provided with a switch 58,
preferably a foot switch, to the output circuit system of the
electrosurgical unit 52. Such a unit is conventional and, in
general, comprises a high frequency current generating system
including a R.F. oscillator which drives a gain controlled power
amplifier that is coupled via a step-up transformer and coupling
capacitors to the active electrode 54. The unit has a suitable
receptacle 60 in which the terminal plug 48 is inserted.
The grounding cable 40 is a twin lead wire cable with the jack plug
48 being a common plug for both lead wires. The plug has two spaced
apart electrodes or contact points 62 and 64. Thus, when the plug
48 is inserted in the receptacle 60 in the electrosurgical unit or
diathermy machine 52, as shown schematically in FIG. 1, the lead
wire 42 of the grounding cable is carried to the ground terminal 66
while the other lead wire is carried to a monitoring device 68.
The monitoring device is of conventional construction and functions
either to sound an alarm and/or deactivate the electrosurgical
unit. Generally speaking, the monitoring device has a solenoid and
the lead wire 44 in the grounding cable 40 establishes a continuous
circuit from the electrosurgical unit 52 to the indifferent
electrode and back again which holds open the solenoid. As soon as
this circuit is broken, as above described, e.g., by the connector
38 becoming somehow impaired or loosened from the stud 22 of the
indifferent electrode 20, when using a split contact plate, the
circuit is broken, the solenoid closes and the monitoring device 58
initiates its alarm and/or deactivating action.
However, it is obvious, as far as the present invention is
concerned, and as previously pointed out, that the cable 36 can be
a single wire cable which merely is a grounding wire. The other
wire 44 can be eliminated if the machine 56 does not possess the
conventional monitoring device or system.
As shown in FIG. 1, the patient P is connected via unipolar limb
leads 70 and 72 to the central terminal 74 of a conventional
electrocardiograph machine 76. The machine is provided with the
usual three-prong plug, one prong of which constitutes the
ground.
As is well known, the conventional electrocardiograph machine, such
as the machine 76 in FIG. 1, is provided with the usual central
terminal connection 74 from which a series of electrical leads
extend. Ordinarily, at least four such leads extend from the
central terminal connection 74 to the arms and legs of the patient.
There is also a second terminal, commonly referred to as the
exploring terminal, from which an exploratory lead extends, this
lead being designed for successive application by the operator of
the machine to various portions of the chest.
However, for purposes of its use in electrosurgical procedures, it
is common to use three EKG electrodes, one of which is used as a
ground connection to the EKG monitor. In accordance with the
present invention, an interconnecting wire 78 is connected between
the EKG 76 and the connector 38 so as to eliminate the need for the
conventional EKG ground electrode. In this respect, as shown in
FIG. 2, the end portion 50a of the body 50 of the connector 38 is
provided with a female socket or receptacle 80 in which the jack
plug 82 of the interconnecting wire 78 is socketed. The wire has a
similar jack plug 83 provided on its opposing end and such jack
plug fits in the central terminal connection 74 (FIG. 1). In this
manner, the EKG and the electrosurgical unit are groundingly
interconnected.
By virtue of the interconnecting wire 78, the patient is provided
with two ground sources, one the EKG 76 and the other the diathermy
machine or electrosurgical unit 52. By utilizing the
interconnecting common grounding wire 78, further advantages can be
obtained. One advantage is a reduction of monitor interference when
the electrical surgical unit is in a stand-by position. Another
advantage is the elimination of potential grounding hazards
possible through the conventional EKG electrode should failure
occur in the electrosurgical ground unit. Another advantage resides
in the elimination of the conventional EKG ground electrode.
The connector 38, as shown more particularly in FIGS. 3-8, includes
the body portion 50, which is solid and which is molded or
otherwise formed from the various plastics materials, as
aforedelineated. Preferably, the body portion is formed from clear
material as is the terminal plug 48 and the casing or sheathing 46
of the grounding cable 36. Such transparency is desirable since it
permits the operator, prior to use, to visually inspect the entire
grounding cable assembly for any obvious breakage or damage.
The body portion 50 has a rear end portion 50a in which one end of
the cable with its enclosed lead wires is inserted. Such end
portion 50a houses the jack receptacle 80 for the interconnecting
grounding wire 78. The body has a front end portion 84 and it has a
top side or face 86 and a bottom side or face 88.
A contact plate 90, formed of metal or other conductive thin sheet
material, is securely superimposed on the bottom face 88 by rivets
92 or similar fastening means. The contact plate 90 has a rear lip
portion 94 which is bent upwardly and fits within a groove 97
formed in the underside of the rear end portion 50a of the body 50.
The lead wires 42 and 44 of the cable 40 are attached by solder or
the like to the lip portion 94, as shown in FIG. 5. The receptacle
or socket 80 for the interconnecting wire jack 82 is soldered to
the rivet 92a of the contact plate, as shown in FIG. 5. In any
event, the receptacle or socket 80 and the lead wires are in good
electrical contact with the contact plate. All of such contact
points are visible through the upper face of the body portion.
The body 50 is formed with an elongate slot 96 that defines a
trackway and that passes through the front end portion 84, as shown
in FIGS. 4, 5 and 6. The trackway is rectangular and of a width
just slightly greater than the diameter of the stud 22 at its
grooved portion 34 so that the opposing straight side edges 96a and
96b of the trackway slide in the groove, without undue lateral play
and dispose the body portion beneath the shoulder 33. As the
trackway opens through the forward end, the side edges diverge
outwardly so that the open front end of the trackway is defined by
a divergent throat portion 98 which serves to guide the trackway
onto the stud. In this respect, the opposing side edges 100 and 102
of the body portion 50 are formed with recessed finger gripping
areas 104 and 106 whereby the body can be manually manipulated.
The contact plate 90 is provided with a tab 108 which extends
upwardly therefrom and which is disposed perpendicularly wthin the
trackway at the inner edge thereof so that it confronts the inner
lateral end wall of the trackway. The tab is of a width
commensurate with the width of the trackway and is positioned at
the inner end thereof so that it will be engaged by the head of the
stud 22 in the manner shown in FIG. 4. This will insure good
electrical contact between the stud extending from the electrode 20
and the ground cable.
FIG. 5A differs from FIG. 5 in that the contact plate 90 is split
longitudinally at its inner end providing separate longitudinal
plate sections 91(a) and 91(b) and lip portions 94(a) 94(b)
extending from said sections, the split providing opposed, parallel
edge extensions of trackway straight side edges 96(a) and 96(b).
Cable lead wires 44 and 42 are attached to lip portions 94(a) and
94(b), respectively. Interposed fastener head portion 32 and
shoulder 33 (FIG. 6) provide the electrical continuity between both
sections. Obviously, removal of the fastener would interrupt the
continuity.
In order to insure that such electrical contact is maintained and
to lock the connector onto the stud, a locking means 110 is
provided adjacent the outer or open end of the trackway 96 and at
the front end portion 84 of the connector body 50. Such locking
means includes a pivoted lever 112 formed of non-conductive
material and preferably formed of the same clear material as the
body 50 of the connector. The lever has a flat body portion 114 and
the top wall 86 of the connector body 50 is formed with a cavity or
depression 116 of a size and shape approximating the geometrical
shape and size of the body of the lever. The lever body is adapted
to seat in such depression or cavity, as shown in FIGS. 3 and 4.
The lever body has a tail end portion 118 which is mounted on a
pivot pin 120 that is fixed transversely between the opposing side
walls of the depression at the forward end portion 84 of the body.
The pivot pin is positioned, as can be seen from FIG. 4, in a plane
above the plane of the bottom wall of the depression so that the
body portion 112 of the lever seats on the bottom wall and is
disposed below the pivot axis so as to be locked in its seated
position.
The lever body, as can be seen in FIGS. 2 and 4, has an integral
cam bar 122 formed on its underside and providing a cam surface 124
which is adapted to engage the head 32 of the stud 22, as shown in
FIG. 4 so as to clampingly hold the head tightly against the
contact tab 108. Thus, when the lever is in its down or seated
position, the cam engages the head to lock the connector onto the
stud. The bar is of a width to fit in the trackway behind the pin
22.
The lever has a free end which is provided with an angular lip 126
which extends upwardly and forwardly when the lever is in its
seated position, as shown in FIG. 4. In such position, the lip
projects above the top surface of the wall of the connector body
50. The lip serves as a finger gripping means so as to move the
lever upwardly and downwardly about its pivot axis.
For the purpose of locating the cable 36 and the interconnecting
grounding wire 78 so as to hold them out of any conflicting
position, with respect to the patient, surgeon, and other operating
room attendants, a clamping means 128 is provided, as shown in FIG.
2. The clamping means includes a bar 130, having a guide
arrangement 132 through which the cable and wire are passed. The
bar terminates in an alligator clip 134 that can be attached to a
patient covering sheet or other holding means readily accessible to
the operating table.
In use, the first step that must be taken is to visually inspect
the connector 38 by locking through the transparent body 50 so as
to inspect the contacts for the interconnecting grounding wire 78.
The wires 42 and 44 should be visually inspected as should the
contacts in the terminal plug 48. Since the terminal plug 48 and
the body portion 50 of the connector are formed from a clear
material, such visual inspection can be readily carried out. Also,
due to the transparency of the sheating 46 for the cable, the
continuity of the wires 42 and 44 can be easily visually
determined.
The next step requires the insertion of the plug 48 into the proper
receptacle 60 in the electrosurgical generator 52. Prior to this,
the electrosurgical grounding pad 10 has been wrapped around the
arm of the patient P, as shown in FIG. 1. The operator then grasps
the body of the connector 38 with the thumb and middle finger of
one hand being disposed in the recessed or cut-out areas 104 and
106 on the sides of the connector. The connector is held and
slidably placed over the head 32 of the stud 22 so that the
trackway slides in the groove 34. In this respect, it is to be
noted from FIGS. 5 and 5A that the contact plate 90 has a trackway
90a formed therein complemental to and underlying the trackway in
the body portion. However, the side edges of the trackway 90a in
contact plate 90 protrude inwardly of the sides of the trackway in
the body 50 of the connector. Thus, the stud will engage the side
edges 96a of the trackway in the contact plate. This is easily
determined by visual inspection.
The body is slid over the stud until the contact tab 108 abuts the
stud 22. At this point, the locking lever 112 is pressed downwardly
with the forefinger while holding the connector body between the
thumb and middle finger. A positive snapping action takes place and
the connector is locked onto the stud.
While the connector 38 is especially designed for use in the
disclosed electrosurgical environment, it can be appreciated that
the same possesses utility for use in other akin or dissimilar
environments.
Thus, in this respect and in regard to the other details of the
inventive concept, as herein disclosed, it is to be understood that
such specific disclosure is merely exemplary. And the inventive
concept is only to be interpreted in accordance with the terms and
scope of the appended claims.
* * * * *