Surgical instrument and method

A surgical instrument useful for laparoscopic surgery comprising an insulated shaft, a control means and a connection to an electrosurgical radiofrequency power source, its distal end being of general J-hook form having a tissue-engaging ledge, and the shaft supporting a tissue-engaging clamping or cutting member movable toward the ledge in response to the control means so that an artery or other tissue in the pocket of the J-hook can be clamped or cut while radiofrequency current is applied. Instrument constructions disclosed incorporate one or two clamping members and a cutting member arranged such that with actuation, the clamping member(s) engages the ledge before the cutting member, and, by selective actuation of the electrosurgical power source, coagulation current can be applied while clamping an artery or other tissue against the ledge to stop flow of blood, and by further actuation of the control and suitable current to the cutting member, the artery or tissue may be cut. Selector means enable movement of one and prevent movement of one of the members during actuation; bipolar or monopolar energization is employed; the relatively long leg of the J-member has portals. Communicating through a lumen in the shaft for infusion or aspiration of fluid; the distal end surface of the J-hook defines a cutting edge for blunt dissection; and the control means comprises a single actuatable member by actuator rods for sealing clamp and cutting members, while a compression spring associated with the actuating rod of the sealing clamp member compresses when the clamp member is stopped, in clamping action upon the artery or tissue while cutting of tissue thereafter proceeds. A diamond film on tissue-engaging surfaces of a clamp, grasping or cutting surgical instrument improves heat transfer between tissue and instrument.

BACKGROUND OF THE INVENTION 
The invention relates to surgical instruments useful in endoscopically 
guided procedures and in particular in laparoscopic surgery. 
Laparoscopic surgery is conducted via the peritoneal cavity by percutaneous 
insertion of appropriate instruments through the abdominal wall. By 
manipulation of the instruments while viewing the surgical site through a 
laparoscope, surgery may be performed on the gallbladder, the kidneys, 
liver and large bowel, for instance. 
Endoscopic surgery in general, and laparoscopic surgery in particular are 
recognized to have considerable advantages over open surgery because of 
the avoidance of large incisions and the discomfort, long and expensive 
hospital stay, and extended period of incapacity required by such 
incisions. Endoscopic procedures instead employ a few small penetrations 
of the body, which lessen the patient's discomfort, and reduce the time 
and expense of the hospital stay and the patient's period of incapacity. 
Current methods of laparoscopy require filling the peritoneal cavity with 
carbon dioxide gas via an inflation device and maintaining inflation 
pressure. The gas expands the cavity by distending the abdomen, which 
provides room in which to maneuver the instruments to the selected 
surgical site. The surgeon uses a variety of instruments to conduct the 
surgical procedures. For instance, instruments used in isolating the 
gallbladder from its blood supply and ducts and then removing it from the 
body via one of the abdominal penetrations include J-form tissue-pulling 
hooks and retractors of various forms for electrosurgical and laser 
cutting and cauterizing, forceps, blunt-end dissectors, suction devices, 
and hollow trocars through which the various instruments are inserted. For 
the purpose of sealing blood flow in arteries and the like, a device for 
applying a sealing clip to the artery has been employed, for instance, the 
Endoclip available from U.S. Surgical, Inc.; typically it is inserted 
through one of the trocars after other instruments such as J-shaped 
retractors pull the artery into an exposed position. With the removal and 
introduction of each instrument through a trocar, carbon dioxide escapes 
from the peritoneum, and the supply must be replenished to maintain proper 
inflation, usually by manual methods. Additionally, electrosurgical and 
other cauterizing devices for laparoscopic or other types of surgery 
frequently stick to tissue due to the heat generated. One method of 
cooling has involved water cooling of the devices. 
The number of required instruments and their repeated insertion and removal 
increases the time required for the procedure and its cost. It has been 
recognized that reduction in the time required for the procedure is highly 
desirable to enable more procedures to be performed at lower cost and to 
reduce physician fatigue. 
SUMMARY OF THE INVENTION 
According to the invention, it is realized that by modifying the J-hook 
laparoscopic instrument or similar instruments, additional important 
functions can be performed in endoscopic surgery with significant effect 
on the efficiency and duration of the surgical procedures, and in some 
instances improved results can also be obtained. 
According to one aspect of the invention, a surgical instrument useful for 
laparoscopic surgery is provided comprising an insulated shaft extending 
between proximal and distal ends, the proximal end having a control means 
and a connection to an electrosurgical radiofrequency power source; the 
distal end being of general J-hook form having a tissue-engaging ledge on 
the proximal side of the bottom of the J-hook; and the insulated shaft 
supporting a tissue-engaging clamping or cutting member movable axially, 
distally of the instrument toward the ledge in response to the control 
means whereby tissue such as an artery hooked in the pocket of the J-hook 
can be engaged on opposite surfaces for clamping or cutting while 
appropriate radiofrequency current from the power source is applied to the 
tissue. 
Preferred embodiments have one or more of the following features. 
The instrument includes at least one clamping member and one cutting member 
arranged such that upon actuation of the control means the clamping member 
engages the ledge of the J-hook before the cutting member, whereby, by 
selective actuation of the electrosurgical power source, coagulation 
current can first be applied while the clamp clamps an artery or other 
tissue against the ledge on the inside of the J-hook, thereby to seal the 
artery or coagulate the tissue to stop bleeding, and thereafter by further 
actuation of the control and actuation of the power source to provide 
current to the cutting member, the artery or tissue may be cut by 
cooperative action of the cutting member and the ledge. 
The instrument has two clamp members, one on each side of the cutting 
member. 
The clamp members are movable together towards the ledge by the control 
means. 
The instrument includes selector means which enable movement of at least 
one of the members while preventing selected movement of one of the 
members during actuation of the control means. 
The instrument is constructed to apply bipolar electrosurgery energization 
between the J-hook and the movable member or members. 
The instrument is constructed to apply monopolar electrosurgery 
energization to the J-hook and the movable member or members for current 
flow to a grounding pad associated with the patient. 
The relatively long leg of the J-member of the instrument comprises a 
hollow tube having a plurality of portals, the hollow tube communicating 
through a lumen in the shaft to a proximal fluid connection for infusion 
or aspiration of fluid from the surgical site via the portals; preferably 
the fluid connection has a Y-connection suitable for connection to both 
infusion means and aspiration means enabling alternate infusion and 
aspiration through the portals and lumen. 
The distally disposed end surface of the J-hook of the instrument is shaped 
to define a cutting edge for blunt dissection. 
The passage through the shaft of the instrument which houses the sealing 
clamp members and the cutting members is of rounded formation, the 
clamping members have planar longitudinal inside surfaces parallel to and 
spaced apart from one another, and the cutter member is disposed 
therebetween in a manner permitting relative longitudinal motion, the 
outer longitudinal surfaces of the clamp members being of matched 
configuration to the corresponding curved walls of the passage for guided 
movement; preferably, the passage is of oval form and, as viewed in 
transverse cross-section, the clamp members extend along the long sides of 
said oval. 
The control means of the instrument comprises a single actuatable member 
constructed to apply axial motion to actuator rods associated with the 
sealing clamp and cutting members, a compression spring associated with 
the actuating rod(s) of the sealing clamp member(s) constructed to 
compress while the sealing clamp member is stopped in clamping action upon 
the artery or tissue while further motion of the actuatable member causes 
the cutter to cut the tissue, preferably, means are provided to adjustably 
vary the preloading of the spring to enable adjustment of the pressure 
with which the tissue is clamped before cutting or the distance of offset 
between the ends of the clamp and the cutting member. 
Finally, a diamond film or layer on tissue-engaging surfaces of a clamp, 
grasping, or cutting surgical instrument can improve heat transfer between 
tissue and the instrument. This can e.g. reduce sticking of tissues to the 
instrument. This feature applies both to laparoscopic surgical instruments 
and instruments for other types of surgery. 
Other features and advantages of the invention will become apparent from 
the following detailed description and from the claims.

STRUCTURE AND OPERATION 
Referring to FIGS. 1 and 6 the main body of the multipurpose laparoscopic 
surgical instrument 10 comprises a rigid insulated shaft 12 which has a 
control section 14 at its proximal end and a J-hook formation 16 at its 
distal end. The instrument is most preferably made of sterilizable 
stainless steel, and the shaft is approximately 32 cm in length, L, and 
4.8 mm in diameter, D, constructed for insertion through a trocar to a 
surgical site within the body. The insulation may be provided by a 
fluorocarbon coating such as Teflon TM from duPont. 
The control section 14 has a fixed handle part 34 and a movable trigger 
part 36. Also, at the proximal end, the shaft 12 has a single lumen 
suction/irrigation portal 18 from which extends a Y-connector 20. One 
branch of the Y-connector 20 is shown connected to a suction tube, which 
leads to a suction syringe 26. The other branch of the Y-connector 20 is 
shown connected to an irrigation tube, which leads to an irrigation 
syringe 28. This portion of the instrument provides selectable suction and 
irrigation through lumen 50 which extends through shaft 12 to the distal 
end of the instrument. In addition, an electrical connector 30 extends 
from the shaft 12 for connection to an electrosurgical radiofrequency 
power source 31 which is associated with a control, such as a foot switch. 
At the distal end, the J-hook formation 16 is formed by a hollow tubular 
leg 40 of diameter D.sub.1, e.g. 2 mm, extending L.sub.1, e.g. 6 mm, 
beyond the distal end of shaft 12, and by cross-member 42 joined to the 
distal end of leg 40. Cross-member 42 defines a ledge 62 on its proximal 
side (inside surface of the J) and a serrated cutting edge 64 on its 
distal side, see FIG. 2. The serrated edge 64 as seen in plan in FIG. 3 
tapers to a cutting edge suitable for blunt dissection of tissues by 
end-wise, distal movement of the instrument. The hollow leg 40 of the 
J-hook 16 has a plurality of suction/irrigation portals 38 communicating 
with lumen 50. The J-hook 16 has returning tip 44 on the free end of the 
cross-member 42. Tip 44, points proximally for hooking purposes, see FIG. 
2. The thickness of the cross-member 42 and the hook 44, in the direction 
normal to the plane of FIG. 2 is 2 mm, corresponding to the diameter of 
leg 40. 
The rigid insulated shaft 12 conducts electrosurgery power via metal leg 40 
to the cross-member 42. Parallel to the suction/irrigation lumen 50, a 
longitudinal passage 52 of oval cross section extends through the shaft 
12. This passage houses two sealing-clamp bars 54 and an electrosurgical 
cutting knife 56. The distal ends of the sealing/cutting bars are flat and 
constructed to press against matching anvil surfaces provided by the 
cross-member 42, see FIG. 5. The outer longitudinal side of each sealing 
clamp 54 is crescent shaped to conform to the corresponding inside surface 
of oval passage 52, while the inside longitudinal surface of the clamps 
are planar, parallel and spaced apart. The cutting knife 56 lies in the 
space between the two clamps 54. In the distal region the knife extends 
the full dimension of oval passage 52, as shown in the cross section of 
FIG. 4. A knife actuating shaft 72 extends proximally from knife 56 to the 
control section, to transmit axial movement to the knife. In one 
embodiment, the exposed anvil surfaces and the end surfaces of the sealing 
clamps 54 and the knife 56 have a diamond film for purposes of heat 
transfer in preferred embodiments. Such films may be produced by vapor 
deposition method such as employed by General Electric Superabrasives 
Inc., see for instance Fisher, "Science Newsfront", Popular Science, pp. 
25-26, (Oct. 1990), and Anthony, Banholzer and Fleischer publications and 
patents on this subject, herein incorporated by reference. 
In the first preferred embodiment, a pin 76 is located above the pivot 66 
on the movable trigger part 36 and pivotally connects to shaft 72. The 
knife blade 56 is thereby driven axially by shaft 72. Likewise actuating 
shafts 70, FIG. 6a, for the two sealing clamps 54 are directly driven by 
shaft 72. A yieldable compression spring 74 is captured in spring 
retention sleeve 75, which is fixed to shaft 72 and retains the proximal 
ends of shafts 70. Thus the compression spring is interposed in the drive 
linkage for each clamp, such that when the sealing clamp bottoms on its 
respective anvil surface of the ledge, or upon an artery, vein, duct or 
tissue interposed between the anvil and the sealing clamp, the trigger 36 
is capable of further actuating motion, applying increasing pressure on 
the body-part, but with no further substantial motion of the sealing 
clamps. 
The respective actuating shafts for the sealing clamps are dimensioned such 
that when the trigger 36 is in released position under the influence of 
its return spring 37, the clamps are entirely withdrawn into hollow shaft 
12, and the tissue receiving pocket P formed between the inside ledge 62 
of the J-hook and the end of shaft 12 is entirely open to receive an 
artery, vein, duct or tissue to be retracted or otherwise acted upon by 
the instrument. The actuating shaft 72 for the knife blade is sized in 
length to position the blade even further proximally within hollow shaft 
12 in the manner that during actuation, the sealing clamp can clamp the 
tissue fully before the blade has contact with the tissue. This can permit 
selective clamping and subsequent release, or clamping and sealing by 
application of coagulating current without cutting if desired, or cutting 
may be actuated by increased squeeze on the trigger only after it is 
observed that desired sealing action of the artery, vein or duct under the 
sealing clamp has occurred. 
(Those familiar with gardening may realize the similarity of this action to 
the action of known rose bush pruning devices which incorporate clamping 
and cutting device to clamp a branch securely before the blade engages the 
branch for cutting.) 
A safety latch device 35, having a pivot 78 and disposed to engage a stop 
pin 80, is associated with trigger 36. When set, the device 35 limits the 
motion of trigger 36 to that required for clamping, and when released, it 
permits full travel to enable successive clamping and cutting, see FIG. 6. 
For the preferred bipolar electrosurgical operation the tissue-engaging 
surfaces of the cross member are preferably associated with the positive 
terminal of the rf electrosurgery power supply and the sealing/clamping 
bars and the knife are negative. For such embodiments the interior of the 
oval passage 52 is insulated or other means are employed to electrically 
isolate the respective parts of the instrument and the connecting terminal 
30 is constructed to provide bipolar energization. In the present 
embodiment it is contemplated that during cutting, the current will be 
selected to employ the field-concentrating effect of the knife to cause 
cutting at the knife, while any current at the clamp members will be at 
such a low current density as to be insufficient to cause cutting. In this 
form the instrument can be used for monopolar operation in the 
conventional manner when the clamp and cutting members are withdrawn, by 
use of a conventional grounding pad associated with the patient. In an 
alternative preferred bipolar construction, the clamp members 54 and the 
knife 56 are positive and the cross-member 42 is grounded. If desired, the 
clamp members and their actuators can then be electrically isolated from 
the knife member and its actuator, to enable distinctly different currents 
(e.g. coagulating and cutting currents respectively) to be applied to the 
clamp members and knife, when desired. 
FIG. 5 shows the operation of the distal end of the instrument. By taking 
the section at line 5--5 in FIG. 2, the returning tip 44 of the J-hook 16 
is not shown to enable the sealing clamps and blade to be shown more 
fully. 
In FIG. 5a a blood vessel 84 has been hooked into the pocket P of the 
J-hook 16 after being separated from the surrounding tissue by blunt 
dissection using the novel distal serrated edge 64 of this J-hook 
instrument, or by other techniques. In hooking the tissue the instrument 
has been used in manner normal to J-hooks. The blood vessel 84 lies 
perpendicular to the two sealing clamps 54 and the cutting knife 56 and 
cross-wise over the blunt ledge 62 or anvil of the cross-member 42 of the 
J-hook 16. 
In FIG. 5b, by partially pulling the trigger, the clamps 54 have been moved 
toward the anvil surface of ledge 62 to clamp the vessel in two places. If 
it is only wished to temporarily hold the vessel during the surgical 
procedure, the control trigger may subsequently be released to release the 
vessel, unimpaired. In this case the instrument has acted as a forceps. If 
it is wished to seal the vessel, electrosurgery power is applied at 
coagulating rf current levels when the clamps grip the blood vessel. As a 
result the blood vessel 64 is cauterized and sealed at the positions of 
the clamps by the bipolar radiofrequency current that passes through the 
tissue, so that blood no longer can flow through the vessel. 
In FIG. 5c, after releasing the safety device 35, further squeezing of the 
trigger 36 causes the cutting knife 56 to move through the blood vessel 84 
between the sealed regions, thus severing the blood vessel 84, as desired. 
While it is possible to employ knife edge cutting, or slicing, in the 
preferred form of the present embodiment electrosurgical current of 
cutting quality (or a blend of cutting and coagulating current) is applied 
between the leading part of the knife and the opposed portion of th ledge 
62 of cross-member 42. 
In the embodiment in which the tissue-engaging surfaces (i.e., the anvil 
surface of the cross-member 42 and the distal ends of the clamps 54 and 
the knife 56) are coated with a diamond film, heat transfer between those 
surfaces and the blood vessel 84 can be improved to reduce sticking of the 
blood vessel 84 to those surfaces. 
Referring to FIG. 6 the operation of the internal mechanism for the steps 
of FIG. 5 will be described. The surgeon draws the movable trigger 36 of 
the control 32 proximally toward the fixed handle 34. The movable trigger 
36 attaches to the fixed part 34 at a pivot point 66, but a small upper 
extension 68 of the movable part 36 extends beyond the pivot 66 and 
includes the pin 76 and slot arrangement, as mentioned above. As the 
surgeon draws the movable part 36 proximally, the upper portion 68 with 
the pin 76 moves distally, moving the proximal end of actuating shaft, and 
therewith, shafts 70. The distal motion of the outer shafts 70 causes the 
clamps 54 to move distally, while the distal motion of the inner shaft 72 
causes the cutting knife 56 to move distally. The compression spring 74 
associated with the actuating shaft for each clamp 54 moves with the 
assembly. When the clamps 54 can no longer move distally due to engagement 
with the blood vessel 64 and clamping of it against the anvil, the 
compression of the spring 74 attached to the clamps 54 allows the 
continued motion of the cutting knife 56. The trigger return spring 37, 
assures the return of the clamps and knife distally upon release of the 
trigger. A selector mechanism, such as the safety device 35 shown in FIG. 
6, can be adjusted by the surgeon to lock the movable cutting knife 56, 
such that distance of travel of the trigger is limited so that only 
clamping occurs when the trigger is squeezed. In the present embodiment, 
the trigger 36 advances until the latch 35 comes into contact with the 
stop pin 80. Depressing the latch 35 raises its end opposite the pivot pin 
78 (i.e., the end that contacts the stop pin 80). Such release of the 
latch allows the trigger 36 to continue the stroke. 
In another preferred embodiment the spring-retaining, clamp-supporting 
sleeve 75 is threaded to the actuation rod 72 for the cutting blade. By 
rotating the sleeve on the threads the position of the distal ends of the 
sealing clamp members can be varied relative to the cutting blade. This 
can be employed to vary the relationship of clamping to cutting, relative 
to actuation motion of the trigger, and can as well be used to vary the 
clamping pressure attained prior to cutting. 
As mentioned above, in addition to the clamping and cutting functions, the 
J-hook 16 of the instrument may also be used for simple hooking, and its 
serrated edge 64 permits its use for blunt dissection. Furthermore, the 
portals 38 and lumen 50, together with the attached suction and irrigation 
syringes 26 and 28, permit controlled alternate suction and irrigation of 
the surgical area through the multiple suction/irrigation portals 38 in 
the hollow tubular leg 40 of the J-hook 16. Thus during the surgery e.g. 
after an artery is hooked but before sealing and cutting, blood in the 
field may be aspirated, saline introduced for washing, and further 
aspiration performed for cleaning th field prior to the electrosurgery. 
Similarly, after cutting an artery, the instrument can again be used for 
an aspiration, infusion sequence. This suction/irrigation feature thus 
further reduces the usual number of instrument interchanges required 
during surgery, minimizing the need for interruptions in the procedure and 
loss of inflation gas. 
For further understanding of the use of the instrument, we refer to FIG. 7. 
A laparoscope 90 is introduced through a 10 mm trocar into the peritoneal 
cavity through the upper part of the patient's umbilicus and directed 
toward the liver. The peritoneal cavity is then inflated with carbon 
dioxide gas. A 5 mm trocar is inserted near the gallbladder fundus and a 
forceps 92 is introduced and used to grasp the fundus. A 5 mm trocar is 
inserted into the mid-clavicle area and the surgical instrument 10 of the 
present application is introduced through it. A 10 mm trocar is inserted 
into the lower right quadrant of the abdomen and a grasping instrument 94 
is introduced through this trocar. The surgeon then operates on the 
patient. 
OTHER EMBODIMENTS 
In another preferred embodiment a selector mechanism is incorporated in the 
instrument to enable selection of which one of the active elements or 
which number of the elements will move upon actuation of the control. 
Depending upon the particular selector mechanism and its setting, it is 
readily possible for the surgeon to lock the movable cutting blade, so 
that only clamping occurs upon squeeze of the handle, or for the surgeon 
to select only the cutting blade for movement, or to select one or the 
other of the clamps to move. In another preferred embodiment multiple 
triggers are provided for the respective elements, and appropriate safety 
latches can be included. In other preferred embodiments, only a single 
clamp is provided, with and without a cutting blade, and in another 
preferred embodiment only a cutting blade is provided. 
Other embodiments of the invention include various combinations of the 
coagulation, cutting and suction/irrigation functions. In these 
embodiments, too, the instrument can have a knife, but no clamps; or an 
instrument can comprise a J-hook having a serrated edge for blunt 
dissection without including either the knife or the clamps and either 
with or without suction/irrigation. There can be one clamp used alone or 
located to one side of the cutting knife. Multiple triggers for the 
various movable elements and safety catches can be again included. Other 
than J-hooks per se, equivalents forms can be employed to perform the 
functions described. 
These and numerous other embodiments will be within the spirit and scope of 
the claims.