U.S. patent application number 12/790309 was filed with the patent office on 2011-12-01 for fluid-assisted electrosurgical devices, and methods of manufacture thereof.
This patent application is currently assigned to SALIENT SURGICAL TECHNOLOGIES, INC.. Invention is credited to Eliot F. BLOOM, Roger D. GREELEY, Chad M. GREENLAW, Steven G. MILLER, Lorenzo C. VACCARELLA.
Application Number | 20110295249 12/790309 |
Document ID | / |
Family ID | 44262923 |
Filed Date | 2011-12-01 |
United States Patent
Application |
20110295249 |
Kind Code |
A1 |
BLOOM; Eliot F. ; et
al. |
December 1, 2011 |
Fluid-Assisted Electrosurgical Devices, and Methods of Manufacture
Thereof
Abstract
This invention provides a fluid-assisted electrosurgical device
to treat tissue in a presence of radio frequency energy and a fluid
provided from the device. The device comprises a handle, a rigid
shaft member distal to the handle, and at least one electrode
distal to the shaft member. The shaft member comprises a shaft
member first body and a shaft member second body joined together
along a length of the shaft member. The shaft member further
comprises a plurality of longitudinally oriented shaft member
passages, with each of the passages having a length defined by the
shaft member first body and the shaft member second body.
Inventors: |
BLOOM; Eliot F.; (Hopkinton,
NH) ; VACCARELLA; Lorenzo C.; (Newmarket, NH)
; GREENLAW; Chad M.; (Somersworth, NH) ; GREELEY;
Roger D.; (Portsmouth, NH) ; MILLER; Steven G.;
(Milton, NH) |
Assignee: |
SALIENT SURGICAL TECHNOLOGIES,
INC.
Portsmouth
NH
|
Family ID: |
44262923 |
Appl. No.: |
12/790309 |
Filed: |
May 28, 2010 |
Current U.S.
Class: |
606/41 |
Current CPC
Class: |
A61B 2018/00029
20130101; A61B 18/148 20130101; Y10T 29/49002 20150115; A61B 18/14
20130101; A61B 18/1482 20130101 |
Class at
Publication: |
606/41 |
International
Class: |
A61B 18/14 20060101
A61B018/14 |
Claims
1. An electrosurgical device comprising: a handle; a rigid shaft
member distal to the handle, the shaft member comprising a shaft
member first body and a shaft member second body, the shaft member
first body and the shaft member second body joined together along a
length of the shaft member; the shaft member including a plurality
of longitudinally oriented shaft member passages, each of the
passages having a length defined by the shaft member first body and
the shaft member second body; and at least one electrode distal to
the shaft member.
2. The device of claim 1 wherein: the plurality of shaft member
passages includes an electrical passage containing an electrical
conductor; and the electrical conductor is electrically coupled to
the at least one electrode.
3. The device of claim 2 wherein: the electrical conductor extends
from a proximal end of the shaft member to a distal end of the
shaft member and into contact with the at least one electrode.
4. The device of claim 3 wherein: the electrical conductor and the
at least one electrode contact one another within a receptacle for
the electrode at a distal end of the shaft member.
5. The device of claim 2 wherein: the electrical conductor and at
least one of the shaft member first body and the shaft member
second body have interconnecting mating features to position the
electrical conductor relative to at least one of the shaft member
first body and a shaft member second body.
6. The device of claim 5 wherein: the interconnecting mating
features comprises a keyway and a key configured to interconnect
with the keyway.
7. The device of claim 2 wherein: the electrical conductor is made
of sheet metal.
8. The device of claim 1 wherein: the at least one electrode
comprises a first electrode and a second electrode; the plurality
of shaft member passages includes a first electrical passage and a
second electrical passage; the first electrical passage contains a
first electrical conductor which is electrically coupled to the
first electrode; and a second electrical passage contains a second
electrical conductor which is electrically coupled to the second
electrode.
9. The device of claim 8 wherein: the first electrical passage is
isolated from the second electrical passage.
10. The device of claim 1 wherein: the plurality of shaft member
passages includes a fluid delivery passage; and the fluid delivery
passage is in fluid communication with at least one fluid outlet
configured to provide fluid to the at least one electrode.
11. The device of claim 10 wherein: the at least one fluid outlet
is at least partially defined by the at least one electrode.
12. The device of claim 10 wherein: the shaft member fluid delivery
passage passes through a shaft member connector portion configured
to connect the shaft member fluid delivery passage with fluid
delivery tubing within the handle; and the shaft member connector
portion is defined by at least one of the shaft member first body
and the shaft member second body.
13. The device of claim 12 wherein: the shaft member connector
portion comprises a barbed connector portion.
14. The device of claim 10 wherein: the at least one electrode
comprises a first electrode and a second electrode; the at least
one fluid outlet configured to provide fluid to the at least one
electrode comprises a first fluid outlet configured to provide
fluid to the first electrode and second fluid outlet configured to
provide fluid to the second electrode; the shaft member fluid
delivery passage includes a first branch and a second branch; the
shaft member fluid delivery passage first branch is in fluid
communication with the first fluid outlet configured to provide
fluid to the first electrode; and the shaft member fluid delivery
passage second branch is in fluid communication with the second
fluid outlet configured to provide fluid to the second
electrode.
15. The device of claim 14 wherein: the first fluid outlet is at
least partially defined by the first electrode; and the second
fluid outlet is at least partially defined by the second
electrode.
16. The device of claim 14 wherein: the first electrode includes a
first electrode fluid delivery passage in fluid communication with
the shaft member fluid delivery passage first branch; and the
second electrode includes a second electrode fluid delivery passage
in fluid communication with the shaft member fluid delivery passage
second branch.
17. The device of claim 14 wherein: the first electrode fluid
delivery passage passes through a first electrode connector portion
configured to connect the first electrode to the shaft member; and
the second electrode fluid delivery passage passes through a second
electrode connector portion configured to connect the second
electrode to the shaft member.
18. The device of claim 14 wherein: the first electrode connector
portion comprises a barbed connector portion; and the second
electrode connector portion comprises a barbed connector
portion.
19. The device of claim 1 wherein: the shaft member first body and
the shaft member second body are joined together by a weld
line.
20. The device of claim 19 wherein: the plurality of longitudinally
oriented shaft member passages are separated from one another along
a common weld line.
21. The device of claim 1 wherein: the plurality of longitudinally
oriented shaft member passages are along side one another. e
22. The device of claim 1 wherein: the plurality of longitudinally
oriented shaft member passages are parallel.
23. The device of claim 1 wherein: the shaft member first body is
made of a thermoplastic material; and the shaft member second body
is made of a thermoplastic material.
Description
FIELD
[0001] This invention relates generally to the field of medical
systems, devices and methods for use upon a body during surgery.
More particularly, the invention relates to electrosurgical
systems, devices and methods for use upon tissues of a human body
during surgery, particularly open surgery and minimally invasive
surgery such as laparoscopic surgery.
BACKGROUND
[0002] Dry-tip electrosurgical devices (e.g. monopolar pencil) have
been known to cause tissue desiccation, tissue sticking to the
electrodes, tissue perforation, char formation and smoke
generation. More recently, fluid-assisted electrosurgical devices
have been developed which use saline to inhibit such undesirable
effects, as well as cool the tissue being treated and electrically
couple the device to the tissue. The present invention provides a
further improvement to fluid-assisted electrosurgical devices by
providing an improved construction which better promotes the
manufacture thereof.
SUMMARY OF THE INVENTION
[0003] This invention provides a fluid-assisted electrosurgical
device to treat tissue in a presence of radio frequency energy and
a fluid provided from the device. In one embodiment, the device
comprises a handle, a rigid shaft member distal to the handle, and
at least one electrode distal to the shaft member. The shaft member
comprises a shaft member first body and a shaft member second body
joined together along a length of the shaft member. The shaft
member further comprises a plurality of longitudinally oriented
shaft member passages. The passages may be parallel and positioned
along side one another, and have a length defined by the shaft
member first body and the shaft member second body. The shaft
member first body and the shaft member second body may be made of a
plastic material.
[0004] In certain embodiments, the plurality of shaft member
passages includes an electrical passage containing an electrical
conductor, with the electrical conductor electrically coupled to
the electrode. The electrical conductor may extend from a proximal
end of the shaft member to a distal end of the shaft member where
it may be in direct contact with the electrode. The electrical
conductor and the electrode may contact one another within a
receptacle for the electrode at a distal end of the shaft member.
The electrical conductor may be made of sheet metal.
[0005] In certain embodiments, the electrical conductor and at
least one of the shaft member first body and the shaft member
second body may have interconnecting mating features to position
the electrical conductor relative to at least one of the shaft
member first body and a shaft member second body. The
interconnecting mating features may comprise a keyway and a key
configured to interconnect with the keyway. In one embodiment, the
electrical conductor interconnecting mating feature may comprise
the keyway, and the interconnecting mating feature of at least one
of the shaft member first body and the shaft member second body may
comprise the key configured to interconnect with the keyway. In an
alternative embodiment, the keyway may be provided with at least
one of the shaft member first body and shaft member second body and
the key may be provided with the electrical conductor.
[0006] In other embodiments, the plurality of shaft member passages
may include a fluid delivery passage, and the fluid delivery
passage may be in fluid communication with a fluid outlet
configured to provide fluid to the electrode. The fluid outlet may
be at least partially defined by the electrode. The shaft member
fluid delivery passage may pass through a shaft member connector
portion configured to connect the shaft member fluid delivery
passage with fluid delivery tubing within the handle. The shaft
member connector portion may be defined by at least one of the
shaft member first body and the shaft member second body, and may
more particularly comprise a barbed connector portion.
[0007] In still other embodiments, the device may comprise a first
electrode and a second electrode, and the plurality of shaft member
passages may include a first electrical passage and a second
electrical passage which are isolated from one another. The first
electrical passage may contain a first electrical conductor which
is electrically coupled to the first electrode, and the second
electrical passage may contain a second electrical conductor which
is electrically coupled to the second electrode.
[0008] In other embodiments, a first fluid outlet may provide fluid
to the first electrode and second fluid outlet may provide fluid to
the second electrode. The shaft member fluid delivery passage may
include a first branch and a second branch. The shaft member fluid
delivery passage first branch may be in fluid communication with
the first fluid outlet configured to provide fluid to the first
electrode, and the shaft member fluid delivery passage second
branch may be in fluid communication with the second fluid outlet
configured to provide fluid to the second electrode. The first
fluid outlet may be at least partially defined by the first
electrode, and the second fluid outlet may be at least partially
defined by the second electrode.
[0009] In other embodiments, the first electrode may include a
first electrode fluid delivery passage in fluid communication with
the shaft member fluid delivery passage first branch, and the
second electrode may include a second electrode fluid delivery
passage in fluid communication with the shaft member fluid delivery
passage second branch.
[0010] In other embodiments, the first electrode fluid delivery
passage may pass through a first electrode connector portion
configured to connect the first electrode to the shaft member, and
the second electrode fluid delivery passage may pass through a
second electrode connector portion configured to connect the second
electrode to the shaft member. The first electrode connector
portion may comprise a barbed connector portion, and the second
electrode connector portion may also comprise a barbed connector
portion.
[0011] In other embodiments, the shaft member first body and the
shaft member second body may be welded together. The plurality of
longitudinally oriented shaft member passages may be separated from
one another along a common weld line or seam.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a front view of one embodiment of a system of the
present invention having an electrosurgical unit in combination
with a fluid source and handheld electrosurgical device;
[0013] FIG. 2 is a graph of the RF power output versus impedance
for the electrosurgical unit of FIG. 1;
[0014] FIG. 3 is graph showing a relationship of fluid flow rate Q
in units of cubic centimetres per minute (cc/min) on the Y-axis,
and the RF power setting P.sub.S in units of watts on the
X-axis;
[0015] FIG. 4 is a perspective view of an electrosurgical device
according to the present invention;
[0016] FIG. 5 is an exploded perspective view of the device of FIG.
4;
[0017] FIG. 6 is a close-up front perspective view of the shaft
member of the device of FIG. 4;
[0018] FIG. 7 is a close-up rear perspective view of the shaft
member of the device of FIG. 4;
[0019] FIG. 8 is an exploded perspective view of the shaft member
of FIGS. 6 and 7;
[0020] FIG. 9 is a close-up cross-sectional view of the shaft
member of FIGS. 6 and 7 taken along line 9-9 of FIG. 6;
[0021] FIG. 10 is a close-up cross-sectional view of the shaft
member of FIGS. 6 and 7 taken along line 10-10 of FIG. 6;
[0022] FIG. 11 is a cross-sectional view of the shaft member of
FIGS. 6 and 7 taken along a length of conductor 70; and
[0023] FIG. 12 is a close-up cross-sectional view of a tip portion
of the device of FIG. 4 with an exemplary fluid coupling to a
tissue surface of tissue;
DETAILED DESCRIPTION
[0024] Throughout the description, like reference numerals and
letters indicate corresponding structure throughout the several
views. Also, any particular feature(s) of a particular exemplary
embodiment may be equally applied to any other exemplary
embodiment(s) of this specification as suitable. In other words,
features between the various exemplary embodiments described herein
are interchangeable as suitable, and not exclusive. From the
specification, it should be clear that any use of the terms
"distal" and "proximal" are made in reference from the user of the
device, and not the patient.
[0025] The invention provides systems, devices and methods for
treating tissue at a tissue treatment site during an
electrosurgical procedure. This is particularly useful for
procedures where it is desirable to shrink, coagulate and seal
tissue against blood loss, for example, by shrinking lumens of
blood vessels (e.g., arteries, veins).
[0026] The invention will now be discussed with reference to the
figures, with FIG. 1 showing a front view of one embodiment of a
system 2 of the present invention having an electrosurgical unit 10
in combination with a fluid source 20 and a handheld
electrosurgical device 30. FIG. 1 further shows a movable cart 12
having a support member 14 which carries a platform 16 comprising a
pedestal table to provide a flat, stable surface for location of
the electrosurgical unit 10. As shown cart 2 further comprises a
fluid source carrying pole 18 with a cross support for carrying
fluid source 20.
[0027] As shown in FIG. 1, fluid source 20 comprises a bag of fluid
from which a fluid 22 flows through a drip chamber 24 after the bag
is penetrated with a spike located at the end of the drip chamber
24. Thereafter, fluid 22 flows through a fluid passage provided by
a lumen of flexible, plastic fluid delivery tubing 26 to handheld
electrosurgical device 30.
[0028] As shown in FIG. 1, the fluid delivery tubing 26 passes
through pump 28. Pump 28 comprises a peristaltic pump and, more
specifically, a rotary peristaltic pump. With a rotary peristaltic
pump, a portion of the fluid delivery tubing 26 is loaded into the
pump 28 by raising and lower a pump head in a known manner. Fluid
22 is then conveyed within the fluid delivery tubing 26 by waves of
contraction placed externally on the tubing 26 which are produced
mechanically, typically by rotating pinch rollers which rotate on a
drive shaft and intermittently compress the fluid delivery tubing
26 against an anvil support. Alternatively, pump 28 may comprise a
linear peristaltic pump. With a linear peristaltic pump, fluid 22
is conveyed within the fluid delivery tubing 26 by waves of
contraction placed externally on the tubing 26 which are produced
mechanically, typically by a series of compression fingers or pads
which sequentially squeeze the tubing 26 against a support.
Peristaltic pumps are generally preferred, as the
electro-mechanical force mechanism, here rollers driven by electric
motor, does not make contact the fluid 22, thus reducing the
likelihood of inadvertent contamination.
[0029] In one embodiment, the fluid 22 is liquid saline solution,
and even more particularly, normal (physiologic) saline solution.
However, although the description herein may make reference to
saline as the fluid 22, other electrically conductive fluids may be
used in accordance with the invention.
[0030] In addition to the use of an electrically conductive fluid,
as will become more apparent with further reading of this
specification, fluid 22 may also be an electrically non-conductive
fluid. The use of a non-conductive fluid may not offer as many
advantages as a conductive fluid, however, the use of a
non-conductive fluid still provides certain advantages over the use
of a dry electrode including, for example, reduced occurrence of
tissue sticking to the electrode(s) of device 30 and cooling of the
electrode(s) and/or tissue. Therefore, it is also within the scope
of the invention to include the use of a non-conductive fluid, such
as, for example, deionized water.
[0031] As shown in FIG. 1, electrosurgical device 30 is connected
to electrosurgical unit 10 via a cable 34 which has a plurality of
electrically insulated wire conductors 32 (shown in FIG. 5) and at
least one plug 36 at the end thereof. The electrosurgical unit 10
provides radio-frequency (RF) energy via cable 34 to
electrosurgical device 30. Plug receptacle 38 of electrosurgical
unit 10 receives the plug 36 of device 30 therein to electrically
connect device 30 to the electrosurgical unit 10. The fluid
delivery tubing 26 may be provided as part of cable 34 and produced
with the electrically insulated wires 32 via plastic
co-extrusion.
[0032] An exemplary RF power output curve for electrosurgical unit
10 is shown in FIG. 2. Impedance Z, shown in units of ohms on the
X-axis and RF output power P.sub.O is shown in units of watts on
the Y-axis. In the illustrated embodiment, the RF power is bipolar
and set to 200 watts. As shown in the figure, for an RF power
setting P.sub.S of 200 watts, the output power P.sub.O will remain
constant with the set RF power P.sub.S as long as the impedance Z
stays between the low impedance cut-off of 30 ohms and the high
impedance cut-off of 250 ohms. Below an impedance Z of 30 ohms, the
output power P.sub.O will decrease as shown by the low impedance
ramp. Above an impedance Z of 250 ohms, the output power P.sub.O
will also decrease as shown by the high impedance ramp.
[0033] Electrosurgical unit 10 has also been configured such that
the speed of pump 28, and therefore the throughput of fluid 22
expelled by the pump 28, is predetermined based on two input
variables, the RF power setting and the fluid flow rate setting. In
FIG. 3, there is shown a relationship of fluid flow rate Q in units
of cubic centimetres per minute (cc/min) on the Y-axis, and the RF
power setting P.sub.S in units of watts on the X-axis. The
relationship has been engineered to inhibit undesirable effects
such as tissue desiccation, electrode sticking, smoke production
and char formation, while at the same time not providing a fluid
flow rate Q at a corresponding RF power setting P.sub.S which is so
great as to provide too much fluid 22 from device 30, which may
result in too much electrical dispersion and excess cooling at the
electrode/tissue interface.
[0034] As shown, electrosurgical unit 10 has been configured to
increase the fluid flow rate Q linearly with an increasing RF power
setting P.sub.S for each of three fluid flow rate settings of low,
medium and high corresponding to Q.sub.L, Q.sub.M and Q.sub.H,
respectively. Conversely, electrosurgical unit 10 has been
configured to decrease the fluid flow rate Q linearly with an
decrease RF power setting P.sub.S for each of three fluid flow rate
settings of low, medium and high corresponding to Q.sub.L, Q.sub.M
and Q.sub.H, respectively.
[0035] Electrosurgical unit 10 may be particularly configured for
use with an electrosurgical device 30 which is a bipolar device.
With a bipolar device, an alternating current (AC) electrical
circuit is created between first and second electrical
poles/electrodes of the device 30. An exemplary bipolar
electrosurgical device of the present invention which may be used
in conjunction with electrosurgical unit 10 of the present
invention is shown at reference character 30a in FIG. 4. While
electrosurgical device 30a of the present invention is described
herein with reference to use with electrosurgical unit 10, it
should be understood that the description of the combination is for
purposes of illustrating the system of the invention. Consequently,
it should be understood that while electrosurgical device 30a
disclosed herein may be used with electrosurgical unit 10, it may
be plausible to use other electrosurgical devices with
electrosurgical unit, or it may be plausible to use the
electrosurgical device(s) disclosed herein with another
electrosurgical unit.
[0036] As shown in FIG. 4, exemplary bipolar device 30a comprises a
proximal handle 40 comprising mating handle portions 40a, 40b.
Handle 40 is preferably made of a sterilizable, rigid,
non-conductive material, such as a plastic material (e.g.,
thermoplastic such as acrylonitrile-butadiene-styrene (ABS),
polycarbonate (PC)). Also, handle 40 is preferably configured
slender, along with the rest of device 30a, to facilitate a user of
device 30a to hold and manipulate device 30a like a pen-type
device. Device 30a also includes a cable 34 which is connectable to
electrosurgical unit 10 and flexible fluid delivery tubing 26 which
is connectable to fluid source 20, particularly via a spike located
at the end of drip chamber 24, which respectively provide RF energy
and fluid 22 to the electrodes 100, 102.
[0037] As shown in FIG. 5, cable 34 of device 30a comprises a
plurality of insulated wires 42 connectable to electrosurgical unit
10 via three banana (male) plug connectors 44. The banana plug
connectors 44 are each assembled with wire conductors of insulated
wires 42 within plug 36 in a known manner. Wire conductors of
insulated wires 42 are connected distally to a handswitch assembly
46, and thereafter wire conductors are connected to crimp terminals
48 which connect to a proximal portion of conductors 70, 72 of
shaft member 50.
[0038] Handswitch assembly 46 comprises a push button 52 which
overlies a domed switch. Upon depression of button 52, the domed
switch forms a closed circuit which is sensed by electrosurgical
unit 10, which then provides RF power to the electrodes 100,
102.
[0039] Referring to FIGS. 6 and 7, rigid shaft member 50, located
distal to handle 40, comprises a shaft member first body 60 and a
shaft member second body 62. Shaft member 50 extends distally from
the handle 40 and supports electrodes 100, 102 in rigid relation to
the handle 40.
[0040] At a proximal end 56 of shaft member 50, fluid delivery
tubing 26 of device 30a is connected within handle 40 to a proximal
barbed connector portion 54 of shaft member 50, which is defined by
at least one of shaft member first body 60 and shaft member second
body 62. To connect fluid delivery tubing 26 to barbed connector
portion 54, the lumen of fluid delivery tubing 26 preferably
interference (friction or press) fit over the outside diameter of
barbed connector portion 54 to provide an interference fit and seal
therebetween.
[0041] As shown in FIGS. 8-10, shaft member first body 60 and shaft
member second body 62 comprise two opposing, mating halves of shaft
member 50 which may form a clamshell design. Shaft member first
body 60 and shaft member second body 62 are joined together along a
length of the shaft member 50, from a proximal end 56 to a distal
end 58 thereof. Shaft member first body 60 and shaft member second
body 62 may particularly be made of a rigid plastic material such
as thermoplastic acrylonitrile-butadiene-styrene (ABS) or
polycarbonate (PC). As used herein, a rigid plastic may be
understood to be a plastic having a modulus of elasticity either in
flexure or in tension greater than 700 MPA (100 kpsi) at 23.degree.
C. and 50% relative humidity when tested in accordance with ASTM
methods D-747, D-790, D-638, or D-882. However, this definition is
not necessarily exhaustive, but merely inclusive. Shaft member
first body 60 and shaft member second body 62 may be joined by
thermoplastic welding, and more particularly ultrasonic welding. In
this manner, a hermetic seal may be provided between shaft member
first body 60 and shaft member second body 62.
[0042] Shaft member 50 includes a plurality of longitudinally
oriented, tubular (enclosed), shaft member passages 64, 66, 82 and
84, with each having a length defined by the shaft member first
body 60 and the shaft member second body 62. The passages 64, 66,
82 and 84 may be parallel and positioned to a side of one another.
As shown, adjacent shaft member passages may be separated from one
another by a common weld line or seam 65 which may hermetically
seal the passages from 64 and 66 from 82 and 84.
[0043] Outer (lateral) passages 64, 66 of shaft member 50 more
particularly comprise electrical passages which are parallel and
isolated from one another, and which contain planar electrical
conductors 70, 72. Electrical conductors 70, 72 extend along the
complete length of passages 64, 66, and extend from entrance
apertures 74, 76, respectively, of passages 64, 66 at a proximal
end 56 of shaft member 50, as well as extend from exit apertures
78, 80 of passages 64, 66 at a distal end 58 of shaft member 50. In
a particular embodiment, electrical conductors 70, 72 are made of
metal, and may more particularly made of sheet metal. In this
manner, conductors are rigid and may contribute to the overall
stiffness of shaft member 50.
[0044] Also at a proximal end 56 of shaft member 50, electrical
conductors 70, 72 are electrically coupled to wire conductors 32
within handle 40 whereby they may receive RF energy conducted
through wire conductors 32 from electrosurgical unit 10. At the
distal end 58 of shaft member 50, electrical conductors are
electrically coupled (via direct physical contact) to electrodes
100, 102, whereby they may conduct the RF energy from
electrosurgical unit 10 to electrodes 100, 102. As shown,
electrodes 100, 102 are seated in distal end electrode receptacles
88, 90 and electrical conductors 70, 72 extend through apertures
78, 80 within the receptacles 88, 90 at the base thereof for the
electrical conductors 70, 72 to make contact with electrodes 100,
102.
[0045] By design, electrical conductors 70, 72 are orientation
sensitive and configured to inhibit improper installation within
shaft member 50. Furthermore, electrical conductors 70, 72 and at
least one of the shaft member first body 60 and a shaft member
second body 62 have interconnecting mating features to position
each electrical conductor 70, 72 relative to at least one of the
shaft member first body 60 and a shaft member second body 62. As
shown in FIG. 11, the interconnecting mating feature of each
electrical conductor 70, 72 comprises a keyway 78 and the
interconnecting mating feature of at least one of the shaft member
first body 60 and shaft member second body 62 comprises a key 80
(shown with shaft member first body 60) configured to interconnect
with the keyway 80. In an alternative embodiment, the keyway 78 may
be provided with at least one of the shaft member first body 60 and
shaft member second body 62 and the key 80 may be provided with the
electrical conductor 70, 72.
[0046] Returning to FIGS. 8-10, inner (medial) passages 82, 84 of
shaft member 50 more particularly comprise fluid delivery passages.
At the proximal end 56 of shaft member 50, passages 82, 84 may
branch from a common proximal fluid delivery passage 86 which
passes through shaft member barbed connector portion 54 and which
is in fluid communication/connected with the lumen of fluid
delivery tubing 26.
[0047] At the distal end 58 of shaft member 50, passages 82, 84 may
be in fluid communication with fluid delivery passages 104, 106
which pass through electrodes 100, 102 and terminate in exit
apertures 108, 110. As shown, apertures 108, 110 are at least
partially defined by electrodes 100, 102, respectively, and more
particularly, are completely defined by electrodes 100, 102,
respectively. In the foregoing manner, exit apertures 108, 110
provide fluid outlets or exits configured to provide fluid 22
therefrom directly onto electrodes 100, 102. Furthermore, as shown,
exit apertures 108, 110 are proximal to a distal end of electrodes
100, 102, as well as located on lateral portions of electrodes 100,
102.
[0048] Thus, during use of device 30a, fluid 22 from fluid source
20 is communicated through a tubular passage provided by lumen of
fluid delivery tubing 26, after which it flows through tubular
fluid delivery passage 86 and tubular fluid delivery passages 82,
84 of shaft member 50, and then to tubular fluid delivery passages
104, 106 of electrodes 100, 102. After flowing through tubular
fluid delivery passages 104, 106 of electrodes 100, 102, fluid 22
may be expelled from fluid outlets 108, 110 onto electrodes 100,
102.
[0049] As shown in FIG. 10, a female proximal connector portion 92,
94 of each electrode receptacle 88, 90 may be configured to form an
interference (friction or press) fit with a male proximal connector
portion 112, 114 of each electrode 100, 102. More particularly, the
female connector portion 92, 94 of each electrode receptacle 88, 90
may comprise a cylindrical recess and the male connector portion
112, 114 of each electrode 100, 102 may comprise a barbed connector
portion 120, 122 configured to fit within the cylindrical recess.
In order to increase the efficiency of the design, the first
electrode fluid delivery passage 104 may pass through the first
electrode connector portion 112 configured to connect the first
electrode 100 to the shaft member 50, and the second electrode
fluid delivery passage 106 may pass through the second electrode
connector portion 114 configured to connect the second electrode
102 to the shaft member 50.
[0050] In the illustrated embodiment, electrodes 100, 102 may be
configured to slide across a tissue surface in a presence of the RF
energy from electrosurgical unit 10 and fluid 22 from the fluid
source 20. As shown, electrodes 100, 102 may be laterally and
spatially separated (by empty space), and configured as mirror
images in size and shape with a blunt distal end surface 116, 118
devoid of edges (to provide a uniform current density and treat
tissue without necessarily cutting). More particularly, each distal
end surface 116, 118 of electrodes 100, 102 may comprise a
spherical surface, and more particularly comprise a hemispherical
surface with an arc of 180 degrees. The spherical surface may be
defined by a uniform radius along the arc, which may be in the
range between and including 1.25 mm to about 2.5 mm. Electrodes
100, 102 may particularly comprise an electrically conductive
metal, such as stainless steel. Other suitable materials may
include titanium, gold, silver and platinum.
[0051] During the manufacture device 30a, electrical conductors 70,
72 are first installed and positioned with shaft member first body
60. Thereafter, shaft member first body 60 and shaft member second
body 62 may be joined by ultrasonic welding. Thereafter, electrodes
100, 102 may be joined to shaft member 50 by inserting male
connector portions 112, 114 of electrodes 100, 102 into female
connector portions 92, 94 of electrode receptacles 88, 90 of shaft
member 50. Prior to inserting male connector portions 112, 114 of
electrodes 100, 102 into female connector portions 92, 94,
electrodes 100, 102 may be heated. In this manner, electrodes 100,
102 may heat and soften the female connector portions 92, 94 of
electrode receptacles 88, 90 during insertion thereof. In this
manner, which may be referred to as heat-staking, the insertion
force may be reduced, and the plastic material defining female
connector portions 92, 94 may flow to better join/grasp with the
barbs and adhesively bond, as well as mechanically bond, to
electrodes 100, 102. In this manner a hermetic seal may be provided
between electrodes 100, 102 and electrode receptacles 88, 90.
Alternatively, electrodes 100, 102 may be ultrasonically welded to
electrode receptacles 88, 90 of shaft member 50.
[0052] At the same time electrodes 100, 102 are joined to shaft
member 50 by inserting male connector portions 112, 114 of
electrodes 100, 102 into female connector portions 92, 94 of
electrode receptacles 88, 90 of shaft member 50, a distal portion
124, 126 of electrical conductors 70, 72 may be inserted into
receptacles 128, 130 of electrodes 100, 102 to establish physical
contact therewith for electrical communication.
[0053] As shown in FIG. 12, one way in which device 30a may be used
is with the longitudinal axis of electrodes 100, 102 vertically
orientated, and the spherical surfaces 116, 118 of electrodes 100,
102 laterally spaced adjacent tissue surface 202 of tissue 200.
Electrodes 100, 102 are connected to electrosurgical unit 10 to
provide RF power and form an alternating current electrical field
in tissue 200 located between electrodes 100 and 102. In the
presence of alternating current, the electrodes 100, 102 alternate
polarity between positive and negative charges with current flow
from the positive to negative charge. Without being bound to a
particular theory, heating of the tissue 200 is performed by
electrical resistance heating.
[0054] Fluid 22, in addition to providing an electrical coupling
between the device 30a and tissue 200, lubricates surface 202 of
tissue 200 and facilitates the movement of electrodes 100, 102
across surface 202 of tissue 200. During movement of electrodes
100, 102, electrodes 100, 102 typically slide across the surface
202 of tissue 200. Typically the user of device 30a slides
electrodes 100, 102 across surface 202 of tissue 200 back and forth
with a painting motion while using fluid 22 as, among other things,
a lubricating coating. Preferably the thickness of the fluid 22
between the distal end surface of electrodes 100, 102 and surface
202 of tissue 200 at the outer edge of couplings 204, 206 is in the
range between and including about 0.05 mm to 1.5 mm. Also, in
certain embodiments, the distal end tip of electrodes 100, 102 may
contact surface 202 of tissue 200 without any fluid 22 in
between.
[0055] As shown in FIG. 12, fluid couplings 204, 206 comprise
discrete, localized webs and more specifically comprise triangular
shaped webs providing fluid 24 between surface 202 of tissue 200
and electrodes 100, 102. When the user of electrosurgical device
30a places electrodes 100, 102 at a tissue treatment site and moves
electrodes 100, 102 across the surface 202 of the tissue 200, fluid
22 is expelled from fluid outlet openings 108, 110 around and on
surfaces 116, 118 of electrodes 100, 102 and onto the surface 202
of the tissue 200 via couplings 204, 206. At the same time, RF
electrical energy, shown by electrical field lines 208, is provided
to tissue 200 at tissue surface 202 and below tissue surface 202
into tissue 200 through fluid couplings 204, 206.
[0056] Device 30a disclosed herein may be particularly useful as
non-coaptive tissue sealer in providing hemostasis during surgery.
In other words, grasping of the tissue is not necessary to shrink,
coagulate and seal tissue against blood loss, for example, by
shrinking collagen and associated lumens of blood vessels (e.g.,
arteries, veins) to provided the desired hemostasis of the tissue.
Furthermore, the control system of the electrosurgical unit 10 is
not necessarily dependent on tissue feedback such as temperature or
impedance to operate. Thus, the control system of electrosurgical
unit 10 may be open loop with respect to the tissue which
simplifies use.
[0057] Device 30a disclosed herein may be particularly useful to
surgeons to achieve hemostasis after dissecting through soft
tissue, as part of hip or knee arthroplasty. The tissue treating
portions can be painted over the raw, oozing surface 202 of tissue
200 to seal the tissue 200 against bleeding, or focused on
individual larger bleeding vessels to stop vessel bleeding. As part
of the same or different procedure, device 30a is also useful to
stop bleeding from the surface of cut bone, or osseous, tissue as
part of any orthopaedic procedure that requires bone to be cut.
Device 30a may be particularly useful for use during orthopedic
knee, hip, shoulder and spine procedures. Additional discussion
concerning such procedures may be found in U.S. Publication No.
2006/0149225, published Jul. 6, 2006, and U.S. Publication No.
2005/0090816, published Apr. 28, 2005, which are assigned to the
assignee of the present invention and are hereby incorporated by
reference in there entirety to the extent they are consistent.
[0058] As established above, device 30a of the present invention
inhibit such undesirable effects of tissue desiccation, electrode
sticking, char formation and smoke generation, and thus do not
suffer from the same drawbacks as prior art dry tip electrosurgical
devices. The use of the disclosed devices can result in
significantly lower blood loss during surgical procedures. Such a
reduction in blood loss can reduce or eliminate the need for blood
transfusions, and thus the cost and negative clinical consequences
associated with blood transfusions, such as prolonged
hospitalization.
[0059] In an alternative embodiment, device 30a may only have a
single electrode 100 and comprise a monopolar device.
[0060] While a preferred embodiment of the present invention has
been described, it should be understood that various changes,
adaptations and modifications can be made therein without departing
from the spirit of the invention and the scope of the appended
claims. The scope of the invention should, therefore, be determined
not with reference to the above description, but instead should be
determined with reference to the appended claims along with their
full scope of equivalents. Furthermore, it should be understood
that the appended claims do not necessarily comprise the broadest
scope of the invention which the Applicant is entitled to claim, or
the only manner(s) in which the invention may be claimed, or that
all recited features are necessary.
[0061] All publications and patent documents cited in this
application are incorporated by reference in their entirety for all
purposes to the extent they are consistent.
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