Laparoscopic Surgical Instrument And Method
Field Of The Invention
The present invention relates generally to medical instruments and
procedures and more particularly, to an instrument for use in laparoscopic or
endoscopic surgical procedures.
Background Of The Invention
Endoscopic and minimally invasive medical procedures, such as
laparoscopy, have become widely accepted for surgery and illness diagnosis.
This is due to reduced trauma to the patient and reduced hospitalization time.
Other techniques exist for creating a working space within the abdominal cavity,
but the vast majority of laparoscopic operations worldwide are performed using
the technique of pneumoperitoneum.
At the beginning of all laparoscopic cases, a small incision is made,
followed by a small (1cm) hole in the remaining layers of the abdominal wall so
as to gain access to the peritoneal cavity. An alternative method of gaining
access to the peritoneal cavity is to insert a small needle through the abdominal
wall and to instill C02 through this needle into the peritoneal cavity. The
peritoneal cavity is usually inflated to a pressure of about 14cm H20. The
pressure of the pneumoperitoneum must be maintained at all times during the
operation. An automatic insufflation pump keeps C02 flowing to maintain a
preset working pressure. If pressure is lost, the working space collapses,
nothing can be seen, via a video system, and the operation comes to a halt. This
working pressure must be maintained despite the need to introduce and remove
cameras, instrumentation, and the like through the abdominal wall during the
operat on.
The solution to this problem has been the development of laparoscopic
ports. These devices, in their simplest form, consist of tubes which penetrate the
abdominal wall to provide a path for the introduction, removal, and exchange of
instruments, etc. Prior art ports must be inserted through the abdominal wall.
This is usually done by the use of a sharp spike, known in the art as a "trocar,"
which is positioned within the lumen of the port, and inserted into the abdominal
wall so as to pierce it. The trocar is then removed from the lumen of the port.
Prior art ports also incorporate some type of valve or seal mechanism to create
an airtight seal around an instrument as it is slid through the port and into the
abdominal cavity. This is to prevent leakage from the pressurized
pneumoperitoneum. The seals must be efficient, as even seemingly small leaks
can exceed the maximum insufflation rate of C02 pump.
Most laparoscopic operations use pneumoperitoneum and a separate
port for each instrument. For example, for gallbladder removal (laparoscopic
cholecystectomy), two instruments are required for retraction, while another is
required for dissection, then often requiring three ports. An additional port is
required for the video camera bringing the total number of ports required to four
for performing a laparoscopic cholecystectomy. Instruments may be exchanged
through any of the ports at any time. Other common laparoscopic operations
including hernia repair, appendectomy, stomach surgery, and gynecologic
surgery require from three to five ports for performing each operation. Such
procedures commonly involve performing a number of individual acts or functions
within the anatomical cavity including grasping, cutting, coagulating, irrigating,
aspirating, puncturing, injecting, dissecting, cauterizing, ligating, suturing,
illuminating, visua izing and/or co ect ng spec mens or opsy. Endoscop c instruments are often designed to perform only one of the above functions,
requiring several incisions for placement of multiple portals to accommodate a
suitable number of endoscopic instruments for performing the required functions
or necessitating frequent withdrawal and replacement of individual endoscopic
instruments through a single incision. In some instances, an endoscopic
instrument may be inserted into the abdomen of the patent and not removed until
the procedure is completed. Here, no instrument exchange is required, even
though a port is in place.
The majority of laparoscopic ports used are disposable. Reusable,
sterilizable ports are available, but have several drawbacks. In order to
purchase sufficient reusable ports to accommodate a moderate sized operating
room facility several thousands of dollars in capital expenditure is required by the
hospital. Known reusable ports are also somewhat difficult to maintain. Rubber
seals and valves crack and break with repeated use and sterilization.
Maintaining and replacing small seals and parts requiring disassembly of the
port is tedious and often results in lost or damaged parts. Also, the trocar
portion of the apparatus often becomes dull after several uses. Using a port that
is not sharp, or that leaks is frustrating for the surgeon and potentially dangerous
to the patient.
Summary Of The Invention
In one embodiment of present invention, a surgical instrument for use in
performing endoscopic procedures within an anatomical cavity is provided
comprising a handle and an elongate member having a proximal end coupled
w e an e or e ng spose ex erna y o e ana om ca cav y an a s a end for being disposed within the anatomical cavity. The distal end further
includes a pair of opposed, relatively movable jaws that form a grasping portion
operable by manipulation of the handle to releasably grasp a releasable trocar.
The releasable trocar comprises a shank that is adapted for grasping, a
relatively sharp tip and may include a pair of blunt-edge tissue separators that
project outwardly from the outer surface of the trocar.
In an alternative embodiment, the relatively movable jaws define (i) a
grasping portion operable by manipulation of the handle to grasp; and (ii) a pair
of blunt-edge tissue separators that project outwardly from the outer surface of
the jaws so that when the jaws are in a closed position they may be used for
tissue penetration.
In another alternative embodiment of the invention, a portal tube is
sealingly positioned on the elongate member and is operative to move between
(i) a first position in which the portal is in a proximal location on the elongate
member and in spaced relation to the anatomical cavity, and (ii) a second
position in which the portal is in a distal location on the elongate member and in
sealed communication with said anatomical cavity.
In a further embodiment of the invention the optional portal may be used
with either the releasable trocar or the jaw trocar.
A method is provided for gaining access to an anatomical cavity
comprising the steps of providing a surgical instrument formed according to any
one of the foregoing embodiments of the invention. Manipulating the handles of
the instrument so as to close the jaws, and then pressing the jaws against the
tissue of the wall of the anatomical cavity so as to separate the tissue. The jaws
are t en move to an operat ve s te w t n t e anatom ca cav ty. e orego ng method may include the step of positioning a portal between the separated
tissue while maintaining the jaws at the operative site, and may also be
performed with either the releasable trocar or the jaws having a pair of blunt-
edge tissue separators.
Brief Description Of The Drawings
These and other features and advantages of the present invention will be
more fully disclosed in, or rendered obvious by, the following detailed description
of the preferred embodiments of the invention, which are to be considered
together with the accompanying drawings wherein like numbers refer to like
parts and further wherein:
Fig. 1 is a perspective view an endoscopic instrument according to one
embodiment of the present invention;
Fig. 2 is a partially broken away, elevational view of the endoscopic
instrument shown in Fig. 1 ;
Fig. 3 is a partially broken away, elevational view of the endoscopic
instrument shown in Fig. 1 , showing a graspable trocar bit just prior to
engagement with the jaws of the instrument;
Fig. 4 is a perspective view of an endoscopic instrument according to an
alternative embodiment of the present invention;
Fig. 5 is an elevational view of an endoscopic instrument according to
another alternative embodiment of the present invention including an optional
use portal sleeve;
FIG. 6 is a cross-sectional view of the optional use portal sleeve shown in Fig. 5, as taken along line 6-6 in Fig. 5; and
Fig. 7 is an elevational view of an endoscopic instrument according to a
further alternative embodiment of the present invention.
Detailed Description Of The Preferred Embodiment
The following description of the preferred embodiments of the invention
are intended to be read in connection with the foregoing drawings and are to be
considered a portion of the entire written description of this invention. As used in
the following description, terms such as, "horizonal", "vertical", "left", "right", "up",
and "down", as well as adjectival and adverbial derivatives thereof (e.g.,
"horizontally", "rightwardly", "upwardly", etc.) simply refer to the orientation of the
structure of the invention as it is illustrated in the particular drawing figure when
that figure faces the reader. Similarly, the terms "inwardly" and "outwardly"
generally refer to the orientation of a surface relative to its axis of elongation, or
axis of rotation, as appropriate. Also, the terms such as "connected" and
"interconnected," when used in this disclosure to describe the relationship
between two or more structures, means that such structures are secured or
attached to each other either directly or indirectly through intervening structures,
and includes pivotal connections. The term "operatively connected" means that
the foregoing direct or indirect connection between the structures allows such
structures to operate as intended by virtue of such connection.
The endoscopic instrument of the present invention can be utilized in any
type of anatomical cavity. Accordingly, while the invention is described
hereinafter for use with laparoscopy procedures, the invention can be used with
catheters and other small or large diameter tubular or hollow, cylindrical members providing access to small cavities, such as veins and arteries as well
as large cavities, such as the abdomen.
Referring to Figs. 1-3, an endoscopic instrument 10 formed in
accordance with the present invention, includes a housing 12, an outer tubular
member 14 extending distally from the housing 12, an inner tubular member 16
telescopically fitted within the outer tubular member and terminating distally in a
pair of opposed jaws 18 and 20, and a handle portion formed of a fixed handle
24 and a movable handle 26.
More particularly, housing 12 includes longitudinally spaced front and rear
walls 28 and 30 that are oriented perpendicular to a longitudinal axis of
endoscopic instrument 10. A top wall 32 is disposed in substantially parallel
relation to the longitudinal axis. A bottom wall 34 includes a concave forward
portion 36 that curves downwardly from front wall 28 to connect with an upper
end of fixed handle 24. A rearward portion 38 of housing 12 extends proximally
at an angle relative to the longitudinal axis of endoscopic instrument 10 from an
upper end of handle 24 to rear wall 30. A lower end of fixed handle 24 is
configured as an elongate finger loop 40 to accommodate one or more fingers
of a user. Movable handle 26 is pivotally mounted on a pin 42 proximally spaced
from fixed handle 24 and secured internally to a wall or walls of housing 12. A
lower end of handle 26 is configured as a finger loop 44 to accommodate one or
more fingers of the user, and a pair of arcuate mating protrusions, shown by
broken lines at 46 and 48 in FIG. 2, can optionally be carried in opposed relation
on finger loops 40 and 44 for ratcheting engagement during use. Movable
handle 26 includes an arcuate end portion 50 disposed within housing 12 and
defining a plurality of gear teeth 52 on a side of pin 42 opposite finger loop 44. Outer tubular member 14 is open at both ends and extends distally from
housing 12 through an opening in front wall 28. Distal end 54 of outer tubular
member 14 can be blunt as shown, tapered, beveled, slotted or chamfered as
desired or have any other suitable distal configuration. Preferably, outer tubular
member 14 comprises a cylindrical cross-section along its length, and is formed
from a substantially rigid material, such as stainless steel or other biocompatible
metal or polymer material. Proximal end 56 of outer tubular member 14 is
movably disposed within housing 12, and carries a rack 58 in spaced relation to
toothed end portion 50 of handle 26. A pinion gear 60 engages rack 58, and is
mounted on the same shaft as a reduction gear 62 which meshingly engages
toothed end portion 50 of handle 12 to convert relatively small rotary or pivotal
movement of handle 12 into significantly larger linear movement of rack 58.
It will be appreciated that counterclockwise rotation of handle 26 about
pin 42 results in proximal movement of outer tubular member 14 relative to
housing 12 and that clockwise rotation of handle 26 about pin 42 results in distal
movement of outer tubular member 14 relative to housing 12. In a preferred
embodiment, movable handle 26 is biased in a clockwise direction toward fixed
handle 24, for example by use of a torsion spring (not shown) coiled around pin
42 and connected between movable handle 26 and fixed handle 24 and/or
housing 12.
The handle portion of the endoscopic instrument shown and described
herein is exemplary of the types of conventional handle mechanisms suitable for
performing the function of actuating the jaws; accordingly, the handles can have
any configuration to actuate the jaws including, but not limited to, configurations
employing a pair of pivotally connected arms, one fixed and one pivoted arm, a pistol grip with a movable trigger, or resilient U-shaped handle members.
Further, the handle portion of the instrument can be configured to rotate relative
to a pivot axis oriented perpendicular to the longitudinal axis of the instrument so
that, for example, in one position the handles will extend laterally from the
instrument or at a substantially perpendicular angle relative to the longitudinal
axis; while, in another position, the handles will extend proximally from the
instrument like scissor handles.
Inner member 16 includes a tubular portion 64 telescopically fitted within
outer tubular member 14, and defining a lumen or channel 66 through
endoscopic instrument 10. The proximal end of inner member 16 extends
through the proximal end of outer tubular member 14 within housing 12. The
distal end of tubular portion 64 is bifurcated or split longitudinally to form integral
one-piece jaws 18 and 20 in opposed relation, the jaws being normally biased
apart as shown in FIG. 3. Tubular body 64 is preferably formed with jaws 18 and
20 as a single unitary part using a resilient biocompatible material such as, for
example, a spring steel or an elastomehc polymer material having suitable
elastic properties for normally biasing the upper and lower jaws apart while
permitting the jaws to be moved toward one another in response to forces acting
on the outer jaw surfaces and/or cams as a result of relative axial movement
between outer tubular member 14 and inner member 16.
In a first embodiment of the present invention, jaws 18 and 20 cooperate
to define a grasping portion at a distal end having opposed inner surfaces 80
and 82. Jaws 18 and 20 include means 81 for grasping a releasable trocar 83.
More particularly, grasping means 81 may include a combination of indentation,
recess, protrusions or teeth that are arranged for securely holding releasable trocar 83 when closed. Releasable trocar 83 preferably comprises a conical
profile to facilitate the penetration or dissection of tissue, and includes a shank
87, a base 90, and an apex 92. Shank 87 comprises a relatively elongate shaft
that projects outwardly from the center portion of base 90, and includes a series
of indentations, recesses, protrusions or teeth that are arranged in a
complementary pattern corresponding to opposed inner surfaces 80 and 82 of
jaws 18 and 20. Base 90 has a diameter substantially equivalent to that of inner
member 16. Apex 92 is pointed so as to be capable of piercing or separating
tissue without inflicting severe trauma. In some cases, a pair of blunt-edged
blades 94, or tissue separators, are positioned on the outer conical surface of
trocar 83. Blunt-edged blades 94 are arranged in circumferentially spaced
relation to one another, and project outwardly from the conical surface of trocar
83 to facilitate the penetration or .
Instrument 10 is used in connection with the foregoing first embodiment of
the invention in the following manner. Since inner member 16 is fixed relative to
housing 12 actuation of jaws 18 and 20 is controlled by moving outer tubular
member 14 relative to inner member 16. If closed, jaws 18 and 20 can be
opened by moving outer tubular member 14 proximally relative to inner member
16. Movement of outer tubular member 14 over inner member 16 is controlled by
operation of movable handle 26. Counterclockwise rotation of handle 26 about
pin 42 results in clockwise rotation of reduction gear 62 which, in turn, causes an
equal angular rotation of pinion 60. Pinion 60 is of greater diameter than
reduction gear 62 so that, for equal angles of rotation, pinion 60 will produce
greater circumferential displacement. Pinion 60 engages the gear teeth of rack
58 to cause proximal movement of outer tubular member 14 relative to jaws 18 and 20 thereby permitting the jaws to move resiliently to the open position,
shown in FIG. 3. In the open position, jaws 18 and 20 are biased apart such that
grasping means 81 are angularly spaced from one another allowing shank 87 of
trocar 83 to be positioned between jaws 18 and 20. Clockwise rotation of
handle 26 about pin 42 results in counterclockwise rotation of reduction gear 62
and pinion 60 causing distal movement of rack 58 and outer tubular member 14
relative to the jaws so that distal end 54 of outer tubular member 14 will slide
over the jaws in an axial direction causing the jaws to be cammed inwardly from
the open position to a closed position. As the jaws move from the open position
to the closed position, grasping means 81 rotate toward one another to grasp
shank 87. More particularly, the complementary indentations, recesses,
protrusions or teeth engage one another to securely clamp trocar 83 between
jaws 18 and 20. It will be understood that arcuate mating protrusions 46 and 48
latched together to maintain handle 26 in position related to fixed handle 24, and
thereby maintain jaws 18 and 20 in gripping relation with shank 87 of trocar 83.
Once trocar 83 is installed, instrument 10 may be guided, by hand, to the
wall of an anatomical cavity. Instrument 10 is advanced distally through the
abdominal wall with jaws 18 and 20 disposed in a tightly closed configuration
around shank 87 of trocar 83. Once the abdominal wall has been pierced by
trocar 83, the instrument can be manipulated externally of the body to position
the jaws so that trocar 83 may be released and removed from the operative site,
via a retrieval tool that has been positioned within the abdomen through a portal.
Various grasping and cutting functions can be performed at the operative site
using different tools that have been affixed to jaws 18 and 20, via a similarly
arranged shank 87, and by operating the handles of the instrument to open and close the jaws as required.
Movable handle 26 is preferably proximally spaced from fixed handle 24
as shown so that the user can maintain one or more fingers on the stationary
handle 24 while operating the movable handle 26 with the thumb and/or other
fingers of the hand. Movable handle 26 is preferably biased in a clockwise
direction, looking at FIG. 3, toward stationary handle 24 so that, when the
movable handle is released, outer tubular member 14 will be automatically
moved over jaws 18 and 20 to close the jaws together to hold trocar 83 between
the jaws.
Referring to Fig. 4 in an alternative embodiment of the present invention
an instrument 100 is provided with a pair of jaws 118 and 120 comprising a pair
of blunt-edged blades 124, or tissue separators, that are positioned on the outer
surface of jaws 118 and 120. Blunt-edged blades 124 are arranged in
circumferentially spaced relation to one another, and project outwardly from the
outer surface of each jaw 118 and 120. The respective tip portion 126 of jaws
118 and 120 may be complementarily conically shaped so that when jaws 118
and 120 are disposed in a closed position they form a substantially sharp
obturator tip to facilitate the penetration or dissection of tissue. It will be
understood that other profile shapes for jaws 118 and 120 may be used in
connection with the invention, e.g., square, rhomboidal, or any other combination
of flat surfaces and angled corners capabable of tissue penetration.
In use, instrument 100 is guided to the wall of an anatomical cavity, with
jaws 118 and 120 in a closed position. Instrument 100 is advanced distally
through the abdominal wall with jaws 118 and 120 acting as a trocar to pierce
and separate the tissue of the abdominal wall. Once the abdominal wall has been pierced by instrument 100, the instrument can be manipulated externally of
the body to position jaws 118 and 120 adjacent to an operative site. Various
grasping and/or cutting functions can be performed at the operative site using
different portions of the jaws and by operating the handles of the instrument to
open and close the jaws. It will be understood that the inner surfaces of jaws 118
and 120 may include blades, teeth, indentations, or the like that are adapted for
use in laparoscopic surgical procedures. It will also be understood that both
laparoscopic instruments 10 and 100 allow for easier axial manipulation, and at
shallower angles relative to the surface of the anatomical cavity, than with prior
art laparoscopic instruments. Further, the axial movement of instruments 10 and
100 is enhanced due to the low coefficient of friction between the outer surface
of outer tubular member 14 and the edges of the incision.
Referring to Figs. 5 and 6, a further alternative embodiment of the present
invention provides an optional portal 200 that is slidably and sealingly positioned
over a portion of outer tubular member 14 of instrument 210. More particularly,
portal 200 comprises an elongate cannula 215, a frusto-conical tip 218, and a
hub 221. Cannula 215 is formed from a relatively rigid, biocompatible metal or
polymer material, and defines a distal opening 224, a proximal opening 227,
and a longitudinally extending lumen 230 that communicates with both openings.
Frusto-conical tip 218 is formed on the distal end of cannula 215 and surrounds
distal opening 224. Hub 221 projects radially outwardly from the proximal end of
cannula 215 to form an annular shoulder 233. An o-ring seal 236 is positioned
within lumen 230, adjacent to proximal opening 227, and in concentric relation to
hub 221. O-ring seal 236 comprises an inner diameter that is smaller than the
diameter of outer tubular member 14, and is securely fastened to the inner surface of cannula 215 so as to be fixed in place.
Portal 200 is positioned on the outer surface of outer tubular member 14
by simply orienting instrument 210 so that the jaws are positioned in coaxial
confronting relation with proximal opening 227. Once in this position, instrument
210 is moved toward portal 200 so that the jaws enter proximal opening 227 and
lumen 230. As this occurs, o-ring seal 236 sealingly engages outer tubular
member 14, and slides along its surface as portal 200 is slid onto instrument
210.
If, during a laparoscopic procedure, a surgeon determines that a portal is
required, he need only push on hub 221 with sufficient force to cause portal 200
to sealingly slide along outer tubular member 14 until frusto-conical tip 218
enters the abdominal wall through the previously created incision. O-ring seal
236 prevents gas leaking from the pneumoperitoneum through cannula 215. The
outer surface of portal 200 is preferably textured to enhance engagement with
the edges of the incision so as to promote the ceiling and anchoring of portal
200 within the pneumoperitoneum. Portal 200 allows for easy instrument
exchange by the surgeon.
Figures 5 and 7 show embodiments of the present invention wherein a
releasable trocar 83 or a pair of jaws 118 and 120 forming a pair of blunt-edged
blades or tissue separators are combined with a portal 200.
It is to be understood that the present invention is by no means limited
only to the particular constructions herein disclosed and shown in the drawings,
but also comprises any modifications or equivalents within the scope of the claims.