Needle and snare guide apparatus for passing suture

A trocar wound closure system includes a suture passing needle and a guide for directing the needle through the wound site. A distal portion of the needle includes a capture rod with a slot. An obturator tube with a cutout section can be axially actuated to align the cutout section with the slot, and then moved out of alignment so as to capture the suture. The guide includes at least two tracks for directing the needle through the tissue track. A snare loop is located adjacent to the exit of each track, and configured to be actuated from a radially extended configuration to a retracted configuration so as to capture the suture section inserted through each loop. Radially expandable arms at distal section are movable between an expanded configuration and a slender configuration.

BACKGROUND OF THE INVENTION

Field of the Invention

This invention relates to surgical instruments for approximation, ligation and fixation of tissue using a suture, and particularly to the approximation of tissue separated by mean of an endosurgical trocar being inserted into a body cavity.

Description of Prior Art and Related Information

Numerous methods currently exist for performing laparoscopic procedures. One of the more commonly used methods is known as closed laparoscopy which utilizes a sharp needle (e.g., Veress needle) to puncture the abdominal wall and insufflate the abdominal cavity with an inert gas such as carbon dioxide through the needle. This process of insufflating the cavity separates the abdominal wall from the underlying organs creating a gap for the surgeon to work within. A trocar/cannula system is then used to maintain the insufflated cavity and provide a working portal for which instruments can be passed into and out of the abdominal cavity to perform various surgical procedures. When the procedure is completed, it is desirable for the surgeon to close the incision site using suture material to minimize the risk of adverse post-operative events.

One of the post-operative complications associated with this procedure is the incidence of trocar site hernias, where a portion of an organ or fatty tissue protrudes out through the hole in the abdominal wall created by the trocar access portal. It is believed that improper closure, or complete lack of closure, of the incision site at the peritoneum is the primary cause of these hernias which form during the post-operative period ranging from several days to several months following the procedure. Traditional methods of wound site close require an additional set of instruments (suture passers, guides, etc.) to be introduced into the surgery. A number of these instruments have been previously disclosed. However, the prior art related to trocar wound site closure instrumentation are typically cumbersome to use and do not provide for a simple, reproducible, and reliable means of closing the wound site.

BRIEF SUMMARY OF THE INVENTION

A preferred system according to the invention comprises a surgical instrument as well as a surgical instrument set that may have certain functions. First, the system may have the capabilities to provide entry into the abdominal cavity and subsequently insufflating the cavity for use in laparoscopic surgical procedures. In the preferred embodiment, the system comprises a needle apparatus having a sharp needle tip and an insufflation channel to facilitate penetration into the abdominal cavity and insufflation. A unique obturator tip is provided to shield the sharp needle tip upon insertion into the cavity. Second, the system may have the capabilities to close the fascial/peritoneal layer at the trocar wound site in a quick, consistent and reproducible manner at the end of the procedure. To facilitate closure of the wound, the system includes the same needle used in combination with a guide apparatus which has suture capture features disposed at or near the distal tip.

The needle apparatus may also serve as a suture passer, in that it has the ability to carry and retrieve suture through tissue layers for suturing closed the wound site. The needle apparatus also has the ability to insufflate the abdomen during the laparoscopic procedure. The needle apparatus may comprise several components including: a handle, actuation mechanism, a connector for connecting the needle to a gas line, a capture rod, an outer needle shaft, and a spring loaded safety tip on a hollow obturator tube.

In a preferred embodiment, a handle at the proximal end of the needle apparatus allows for single-handed or double-handed use. The handle may also contain a finger loop or loops for additional security while holding the needle. An actuator mechanism may be disposed adjacent to the handle and configured for the deployment and retraction of the capture rod used to secure the suture material within the tip of the needle. The preferred actuator mechanism may include a sliding plunger that translates along the long axis of the handle that moves the capture rod between a first position in an axially extended configuration and a second position in an axially retracted configuration. The actuator may be spring loaded in one direction such that the capture rod is biased to the retracted position. This may allow the suture to be passively captured without actuation of the plunger. The handle and actuator means may be constructed from metals (such as stainless steel, titanium or aluminum) or plastics (such as polyacetal, nylon, polypropylene, poly-ether-ether-ketone, or polycarbonate), or any combination of the two.

A long outer needle shaft may be connected to the proximal handle and extends distally over a length that may range from 2-38 centimeters, or more preferably between 10-20 centimeters. The outer needle shaft may have a sharp tip, or needle peak, at the distal-most point to ease the insertion of the needle through the various tissue layers. The outer shaft may house an obturator tube that has a hollow, unobstructed inner lumen, with a blunt tip. The obturator tube may also house a capture rod used for securing the suture for passing through tissue. The outer needle shaft, obturator tube and capture rod would optimally be constructed from metals such as stainless steel, titanium or aluminum.

The distal-most end of the obturator tube may have a blunt or rounded plug or surface at the tip. The entire obturator tube may be spring loaded to allow for the blunt tip to translate away from the tip of the needle when it is loaded, and passively travel back to the tip of the needle when it is unloaded. The obturator spring may be housed within the handle. The spring loaded obturator would serve as a safety mechanism for protecting the internal organs within the abdomen after the needle is passed through the abdominal wall.

A portion of the wall of the outer needle shaft may be cutout near the distal tip which may be used to create a slot to accommodate the suture during the suture passing process. Similarly, a portion of the wall of the obturator tube may be cut out near the distal tip of the tube to provide an opening for the capture rod to secure the suture to the wall of the outer needle shaft. The window cutout in the obturator tube must be long enough such that it can accommodate the suture as it travels back and forth. Lastly, the capture rod has a slot with one or more ramped faces. A distal ramped surface on the capture rod slot is used to capture the suture against the outer needle shaft. A proximal ramped surface may assist in pushing the suture out of the window in the obturator tube, facilitating the release of the suture from the needle.

The needle capture rod is used to secure the suture to the needle for suture passing activities. Initially the actuator may be pressed to extend the capture rod and expose the slot in the capture rod. A section of suture may be placed into the slot, and the actuator is released to retract the capture rod. As the capture rod retracts, the suture becomes trapped between the distal surface of the slot in the capture rod and the cutout in the outer needle shaft. When the suture needs to be released, the actuator may be pressed again to extend the capture rod. As the capture rod is extended the proximal face of the slot may push the suture material out of the cutout in the obturator tube and away from the needle shaft.

In another preferred embodiment, a luer connector or other quick connect type device may be disposed on the proximal handle to provide an entry passageway for the gas to enter into the needle. The unobstructed inner lumen of the obturator tube may allow for the passage of an inert gas for insufflation of the abdomen.

The guide apparatus may serve dual purposes, as it first may be used to guide the needle through the abdominal wall in a repeatable manner, and second used to capture the suture material after it is passed into the abdominal wall. The guide may comprise a slotted barrel, collapsible barrel tip, plunger, main shaft, cap, suture capturing snare cord, and guide tubes along with various fasteners and springs.

The slotted barrel may have two slotted channels to accommodate the passage of the needle. The entries and exits of the two channels may be spaced 180 degrees radially apart from each other such that the stitch can be placed on opposing sides of the wound. The channels' purpose is to guide the needle repeatably through the same tissue thickness and into the suture snare cord, where the suture can be released. The trajectory of the channels is referenced off the inner wall of the peritoneum such that approximately 5-15 millimeters of tissue bite is achieved from the periphery of the wound. The proximal ends of the channels may have a widened and or tapered opening to ease the entry of the needle into the channels. Slots in the channels will allow for the middle section of the length of suture to be released from the constraints of the guide channels. The width of the slots in the channels should be large enough for the suture to easily be released from the channels, yet small enough to not allow the needle to exit the channel or get caught against it.

The guide may comprise a main shaft that is slidably disposed within the slotted barrel of the guide. The main shaft may be used to actuate the expanding arms, comprising living hinges in the preferred embodiment on the collapsible barrel tip. One or more expanding arms may be used to locate the guide against the inner peritoneal wall as a reference point to ensure consistent tissue bite depth of the needle, as previously described. The main shaft may be spring loaded in a proximal position such that the expanding arms are biased to a radially expanded position where the outer profile of the arms exceeds the diameter of the slotted barrel. As the main shaft moves distally, the arms may be contracted such that aligns their outer diameter with the outer diameter of the slotted barrel in a continuous slender fashion. The main shaft may be connected at the distal end to the barrel tip, and connected to the plunger on the proximal end.

The distal end of the barrel tip may have a blunt tip to minimize the potential of harm or damage to the adjacent tissues during insertion. Moving proximally away from the blunt tip, the outer wall of the barrel tip may have a tapered region that gradually radially increases to the outer profile of the guide as designated by the outer diameter of the slotted barrel. The tapered section may facilitate the ease of insertion of the guide into the trocar wound site.

The barrel tip may have one or more stop tabs that provide a hard stop for the barrel tip as the expanding arms are actuated, to prevent excessive flexion in the hinge material. Along the length of the stop tabs, a cutout section may exist for the snare loop to be retracted into for capturing the suture material against the guide.

The guide may have a slider that is used to actuate the snare cord material. The slider may be slidably disposed on the slotted barrel. Two snare cords may be connected at their ends to the slider body, with a loop formed at the distal tip of the guide. The slider may be spring loaded such that the snare cords are biased into a radially extended position. As the slider is pulled proximally, the snare cord is retracted against the extension arms of the barrel tip. As the slider is released distally, the snare cord is radially extended out and away from the barrel to create two snare loops for the suture to be passed into. The slider may have two tabs that can be used to pull the slider proximally using one or more fingers on each tab. The snare cords may be constructed from a mono- or multi-filament wire that has the flexibility to easily bend and conform to various geometries yet stiff enough to create a self-supported snare loop that extends generally perpendicular to the long axis of the guide. Materials that may be used to construct the snare cord include plastics such as nylon, polyethylene, polyester or polypropylene or metals such as stainless steel or nitinol.

A plunger at the proximal end of the guide may be used to provide a counterforce when pulling on the slider. As the plunger is pushed and the slider is simultaneously pulled, the snares will move into the retracted position first, and then the expanding arms are retracted into the slender configuration. As the slider is released, the spring forces will extend the snares to the extended position and the expanding arms will be converted to the radially expanded condition.

In another embodiment, the snares may include a basket element to prevent the needle from traversing deeply into the abdominal cavity and causing potential harm.

The basic procedural steps of the utilization of the suturing system may flow as follows. At the end of the surgical procedure, the trocar is removed from the body exposing the wound. The slider on the guide is pulled up against the plunger to contract the flexing arms and retract the snares such that the profile of the guide is at its minimum. The guide can then be inserted into the wound with the plunger continually pulled against the slider. The slider and plunger are then released expanding the arms and deploying the snares. The guide can be pulled upward and away from the body cavity until the arms rest against the inner wall of the peritoneum. A short tail at one end of the suture is secured by the capture rod in the tip of the needle. The needle, with suture, is then passed through a first needle channel in the guide and is advanced through the guide, tissue and snare, into the abdominal cavity. The needle then releases the suture into the cavity, and is retracted from the body. A second short tail at the second free end of the suture is then secured by the capture rod in the needle. The needle, with suture, is then passed through the second needle channel in the guide and advanced through the guide, tissue and snare, into the abdominal cavity. The needle then releases the suture into the abdominal cavity and removed from the guide and body. The remaining loop of suture outside the body may then be released from each of the slots in the needle tracks. The slider on the guide is then again pulled against the plunger to retract the snares, capturing the free ends of suture, and contract the flexing arms allowing the guide to be removed from the wound, carrying the suture with it. Once outside the body, the snares may need to be deployed enough to release the free ends of the suture. Lastly, a knot may be tied and pushed down into the wound to close the trocar puncture site.

In an alternative procedure, the guide may be used to place aFIG. 8stitch using two separate sutures rather than a single stitch using only one suture. The guide is initially inserted into the wound as previously described. A short tail at a first end of a first suture is loaded into the needle, passed through the first channel of the guide, and released into the abdominal cavity. At this point a short tail at the second end of the first suture is loaded into the needle, and passed through the second channel. The guide may then be rotated approximately 90 degrees from the initial orientation of the first suture passing. A short tail at one end of a second suture may be loaded into the needle, passed through the first channel of the guide, and released into the abdominal cavity. The needle is retracted and then a tail from the opposing end of the second suture is loaded and passed through the second channel of the guide and released into the abdominal cavity. The slider is pulled and the guide is removed from the wound with all four ends of suture captured in the snares. Knots may then be tied in each of the individual sutures to close the wound.

The basic procedural steps for abdominal entry and insufflation of the cavity may flow as follows. The needle is used to enter the abdominal cavity using standard closed laparoscopic techniques. A gas line is connected to the handle allow for an inert gas to be passed into the abdominal cavity. The inert gas is then turned on until the cavity reaches an appropriate level of insufflation to allow for the procedure to be performed with appropriate visualization. The needle is then removed, and a trocar is inserted into the puncture site to perform the procedure.

In an alternative embodiment, the guide may comprise a monolithic snare where the actuator section, shaft section and snare loops are all integrally formed. The barrel may comprise two half barrel pieces that can be secured together. The barrel defines an inner lumen and at least two diagonal channels in communication with two corresponding window openings adjacent to a distal end of the barrel. Each channel comprises a wider proximal opening that tapers towards a distal exit so as to serve as a fulcrum for the needle apparatus directed therethrough. Each snare loop comprises a tip that may serve as a landmark indicator to position the guide against the internal peritoneal wall.

The snare loops can be completely retracted within the barrel by moving the actuator section and integral shaft section of the snare axially and proximally through the inner lumen. The enlarged tip of each snare loop comprises a positive stop abutting the narrower window opening within the barrel so as to prevent excess travel of the monolithic snare within the barrel.

The guide may comprise indicia on an outer barrel surface to indicate how far to insert the barrel into the abdomen (i.e., until the mark is no longer visible) so as to achieve a more optimal “bite,” namely, the horizontal distance from the puncture location of the needle through the peritoneum to the closest edge of the defect coinciding with the sidewall of the barrel.

An alternative method is provided to achieve a desirable placement of the needle and suture through the tissue, particularly for thinner abdominal walls. Prior to the placing the needle though the tissue, the lateral tip of a snare loop may be used as a landmark while tilting the guide at an angle to the primary guide axis, until the first lateral tip comes in close proximity to or abuts the peritoneum. The tissue area will compress, and placement of the needle will encompassed a greater amount of tissue.

With the tilted guide in position, the suture engaging device, with a first free end section of suture engaged, may be inserted through a first channel while carrying the first section of suture. Once the needle exits the channel it passes through the compressed layers of tissue, and enters the body cavity. As it enters the body cavity, the needle passes through the first snare loop. The needle may release the strand of suture and be removed from the body leaving the suture section loosely inside the expanded snare loop. Thus, the suture section is carried into the body cavity to a point where the suture section intersects and traverses the generally planar opening defined by the expanded snare loop.

The guide is then tilted in the opposite direction, such that the opposite second lateral tip of the second snare loop comes in close proximity to the peritoneum. With the tilted guide in position, the second free end section of suture may then be engaged by the suture engaging device, and inserted through the opposing second channel to place the second end suture section. Once the needle exits the opposing channel it passes through the compressed layers of tissue and enters the body cavity. As it enters the body cavity, the needle passes through the opposing second snare loop. The needle may release the strand of suture and be removed from the body leaving the suture sections within the boundaries of the respective snare loops.

Moving the actuator section away from the barrel retracts the snare loops so as to capture the suture sections542,543. With both suture sections542,543captured, the guide530is retracted from the tissue track, carrying the suture sections542,543. With the guide530and suture sections542,543exposed outside the body cavity, the actuator section533can be pushed toward the barrel531extending the suture snare loops534, and thus releasing the suture sections542,543. A knot can then be tied in the suture sections542,543and secured to provide closure of the wound.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In a preferred embodiment, a system is provided for closing trocar wound sites. The system comprises a suture engagement device and a guide to direct the device through the body tissues.

An improved needle and guide instrument set is further described below as it allows for the surgical placement of suture to be completed “blind,” namely, without the aid of an endoscope for direct visualization of the abdominal cavity. This may be advantageous in certain surgical procedures where an endoscope is not being used or does not provide adequate visualization of the surgical site.

A preferred embodiment of a suture engagement device or suture passing needle, or simply needle,100is shown inFIG. 1. The needle100may simply have a handle101and actuator105at the proximal end12. An outer tube108is connected to the handle101that terminates with a suture capture mechanism107, sharp needle tip109, and spring loaded safety tip112at the distal end14of the needle100, as shown inFIG. 3.

FIG. 2illustrates a closer view of the proximal portion16of the needle100. The base of the proximal end12of the needle100is a main handle or housing101. The handle101may have a finger loop102that may accommodate one or more fingers, as well as a series of one or more grooves103to accommodate the placement of additional fingers. The finger loop102and grooves103may provide the user with a comfortable, secure grip of the device and provide greater control when handling the device100. Slidably disposed within the housing101is an actuator105that may be used to control a suture capture mechanism107at the distal tip of the needle101. At the proximal end of the actuator105, an enlarged surface106may provide an ergonomic location for a thumb or other finger to trigger the actuator105. The length travel of the actuator105may be constrained by a pin123that connects to the actuator105and slides within a slot104on the handle101. The pin123also serves the purpose of rotationally constraining the actuator105.

FIG. 3illustrates a closer view of the distal portion18of the needle100. An obturator tube111may be slidably disposed within an outer tube108, and a capture rod114may be slidably disposed within the obturator tube111. The outer tube108terminates at a sharp tip109that may have two or more beveled edges118to facilitate the ease of passage of the needle100through tissue. The obturator tube111has a blunt surface112at its distal end20and may be used to serve as a safety tip for the needle100. The obturator tube111may be spring loaded such that it can passively travel between an axially extended and retracted position. Initially, the obturator tube111may be biased in the extended position where the blunt surface112extends further distally than the sharp tip109of the outer tube108. As the distal tip of the needle100is pushed into the tissue with enough load to overcome the force of the spring, the obturator tube111may retract proximally, ultimately exposing the sharp tip109of the outer tube108. The sharp tip109and edges118may then minimize the trauma to the tissue layers as the needle100is inserted. Once the tip109of the needle100enters the body cavity, the obturator tube111may passively return to the distally extended position shielding the sharp tip109from inadvertently damaging the tissue structures within the body cavity. The purpose of the capture rod114is to secure the suture to the needle100, in a manner further described below.

InFIGS. 4A and 4B, the suture capture mechanism107at the distal end14of the needle100preferably comprises a channel110in the outer tube108, a cutout section113of the obturator tube111, and a slot115in a capture rod114. The suture capture mechanism107may function through the movement of the capture rod114between an axially extended and retracted position that is controlled by the actuator105at the proximal end12of the needle100. InFIG. 4A, the capture rod114is shown in the extended position such that a strand of suture125can be placed through the cutout113in the obturator111and into the slot115of the capture rod114. In this axially extended position, the obturator cutout113is open to, and aligned with, the capture rod slot115in order to receive the suture125. InFIG. 4B, the capture rod114is shown in the axially retracted position such that the strand of suture125is secured between the channel110of the outer tube108and the distal face117of the slot155in the capture rod114. When the suture125needs to be released, the actuator105returns the capture rod114to the extended position. A proximal face116of the capture rod114, shown inFIG. 4A, may aid in pushing the suture125out of the obturator cutout113and away from the outer profile of the outer tube108.

Cross sectional views of the preferred embodiment of the needle100are shown inFIGS. 5A and 5Bthat illustrate the inner workings of the handle101. A proximal portion22of the obturator tube111may be connected to an obturator hub119. The hub119may have one or more rotational alignment structures such as a flat face120or an alignment post121that prevent the hub119from rotating about a long axis24as it translates back and forth. Additional extrusions128inside the housing101may be necessary to mate with the alignment protrusions120,121on the hub119. The alignment of the hub119is critical to ensure the cutout113at the distal end maintains its alignment for suture capturing. The hub119may also have a cylindrical portion126to accommodate a coil spring122that is used to spring load the obturator tube111. The opposing end of the spring122may connect to the actuator105at a similarly accommodating cylindrical portion127. The capture rod114may be attached to the actuator105with a pin123that passes through a hole124in the actuator and a slot129in the capture rod. As previously described, the pin123may slide within a window104of the housing101that is used to limit the travel and prevent rotation of the capture rod114.

InFIGS. 6A-6C, a preferred embodiment of a guide130may be useful for directing the above described suture engaging device through a body wall. The guide130may be particularly useful for the placement of sutures used in closing wounds or openings through body walls made in surgical procedures to access internal body cavities. Accordingly, the guide130preferably comprises two pathways diagonal to each other and oriented to direct a needle apparatus to both a first internal location to carry and release a first end of a suture, and a second internal location to carry and release a second end of a suture.

An oblique view of the preferred guide130is shown inFIGS. 6A-6C. The guide130may comprise a distal barrel tip140with two radially expanding arms147, two suture snare loops146, a main barrel131with two channels132,136(shown inFIG. 8), a plunger153, and a slider156. The two channels132,136are disposed within the main barrel131to guide the suture passing needle100through the tissue to be sutured, as shown inFIGS. 8 and 12. The slider156may be slidably disposed onto the main barrel131to provide actuation of the suture snare loops146. The plunger153may be slidably disposed onto the main barrel131to provide actuation of the expanding arms147. The expanding arms147may serve as an internal cavity securing mechanism, which is used to secure the guide130against the internal peritoneal wall. The two suture snare loops146serve the purpose of capturing the suture material after it has been passed through the tissue wall. The slider156may facilitate the ease of handling of the guide130.

As the slider156translates with respect to the barrel131, the suture snare loops146move between two positions of radially extended shown inFIG. 6Aand retracted shown inFIG. 6B. When each snare146is in the radially extended configuration, a loop, ring, circle or hoop shape is preferably formed. The snare loop146provides a region for a suture passing needle to pass into and drop off the suture. The snare loop146defines an opening through which the carried suture traverses. When the carried suture is released from the suture engaging device, the suture section intersecting the opening of the snare loop146resides loosely until the snare loop146is retracted. When the snare loop146is retracted the suture material becomes trapped between the snare loop146and the wall of the distal barrel tip140.

Further, as the plunger153translates with respect to the barrel131, the radially expanding arms147at the distal barrel tip140move between two positions of radially expanded, or flared out, as shown inFIG. 6B, and radially contracted, or slender, as shown inFIG. 6C. Each of the expanding arms147preferably comprise a living hinge section, where the material is cut thin at specific locations allowing for the material to flex. It is to be expressly understood that the expanding arms may comprise a variety of structures and mechanisms that are capable of moving between slender and flared out configurations.

As shown inFIG. 7, radially adjacent to the expanding arms147may be one or more distally extending stop tabs143. The stop tabs143are configured to provide a mechanical stop for the distal end cap141of the barrel tip140to collide against preventing excessive flex within the thin sections148,149,150of the expanding arms147. The stop tabs143may also have a slot145cutout in the outer wall that provide a region for the snare loop material146to be housed when the snare loop146is in the retracted state. When a section of suture159is captured within the snare loop146, the slot145may provide additional security to the captured suture159, as opposed to the snare loop146pulling the suture against a smooth surface.

The barrel tip140may comprise a separate component that is assembled to the main barrel131. Two tabs166on the main barrel131may be placed radially opposite to each other. Slots167in the barrel tip140may allow for the tip140to initially slide past the tabs166on the main barrel131. The slots167may have an undercut section168that may be engaged by rotating the tip140and pulling it distally. The gap that is created between the tip140and the barrel131may be filled with a deformable c-shaped clip169to prevent the tip140from dislodging from the barrel131.

The slider156is slidably disposed on the main barrel131as it can travel between a distal position shown inFIG. 6Aand a proximal position shown inFIG. 6B. Two finger tabs154are preferably disposed near the distal end of the slider156and configured to be grasped with one or more fingers. The thumb or palm of the hand may then be pressed against the proximal face157of the plunger153. The finger tabs154may then be pulled proximally to actuate the guide130with the plunger153being used to provide a counterforce. The slider156can reach a stop, achieved by either an internal feature of the slider156engaging the main barrel131or the snare loops146being fully retracted. Additional force between the slider156and the plunger153may overcome the counterforce translated to the plunger153by a spring. The plunger153can then move axially to actuate the expanding arms147to the slender contracted state. Upon release of the force between the slider156and the plunger153, the plunger153can return to the original position and result in the expanding arms147reverting to the radially expanded position. The slider156may be biased to the distal position by a spring that passively returns the slider156to the distal position when released, thus resulting in the suture loops146reverting back to the radially extended position. It may be appreciated that biasing the guide130in this configuration may allow for the surgeon to have his hands free from operating the guide130such that work with other instruments may be conducted once the guide130has been inserted into the trocar wound.

In the preferred embodiment, the guide130provides two different, diagonal pathways for a suture passing needle apparatus and thus comprises first and second channels132,136as more clearly shown inFIG. 8. The channels132,136are directionally diagonal to the long axis “24” of the guide130at some acute angle, preferably in the range of 5-30 degrees. The angle of the channels132,136controls the depth of bite into the tissue, such that a greater angle provides a greater bite of tissue. Angular spacing between entries to the channels132,136are preferably equal (i.e., equiangular) depending upon the number of channels, e.g., 180 degrees apart if there are two channels, 120 degrees apart if there are three channels, etc. Two separate entry points133,137are provided on the channels132,136for a suture passing needle to enter the guide130, as well as two separate exit points134,138. Each channel132,136has a slot135,139, or opening that allows for a strand of suture to be removed from the channel. This may be necessary to complete the suture loop in the tissue.

The internal workings of the guide130are shown inFIGS. 9A-9C, which illustrate cross-sectional views through the center of the guide130. An inner shaft158spans from the proximal end30to the distal end32of the guide130and is used to actuate the expanding arms147. The shaft158connects at the distal end32of the guide130to the distal end cap141of the barrel tip140, and connects at the proximal end30of the guide130to the plunger153. A retaining ring, heat stake, or other mechanical fastening means may be used to secure the shaft158to the plunger153. When the slider156is pulled into the proximal position as shown inFIG. 6B, a counterforce is applied to the plunger153. Upon the slider156reaching the full proximal extension, further pushing on the plunger153advances the shaft158distally which in turn advances the end cap141on the barrel tip140distally, causing the expanding arms147to radially contract as shown inFIG. 6C. Upon release of the plunger153and slider156, the shaft158may passively return to its native proximal position, pulling the end cap141with it and causing the expanding arms147to radially extend.

Two springs are used to bias the guide130into the configurations shown inFIGS. 6A and 9A, with the radially extended arms147and snare loop146expanded, and the plunger153in the proximal position. A slider spring155is used to bias the slider156to the proximal position. InFIG. 9C, one end of the slider spring155is captured at the proximal end40of the main barrel131by two spring capture tabs173. The opposing end of the spring155rests against an inner edge174of the slider156, forcing the slider156to a proximal position. InFIG. 9B, a plunger spring165is used to bias the distal barrel tip140in the proximal position. The spring165is captured between inner shaft158and the proximal face of track support170connected to the barrel tip140. This plunger spring165forces the inner shaft158and plunger153in a proximal position, pulling the barrel tip140proximally as well.

InFIG. 9C, the free ends of a snare cord loop146may be captured in a retaining cap175that is fixed to the proximal end of the slider156. The snare cord146may traverse distally down the guide130either through snare channels176inside the main barrel131or guide tubes171that span through a portion of the length of the main barrel131. The snare channels176or guide tubes171may be used to constrain the snare cord material146and prevent it from bunching up or buckling under load as it travels proximally and distally within the guide130.

FIGS. 10A-10Billustrate the laminate component construct that provides tracks172within the barrel tip140. The track support170is positioned between two track side panels177. The tracks172may be used to guide the snare cord146from a position within the barrel tip140, parallel to the long axis of the guide130to a position exiting the barrel tip140relatively perpendicular to a long axis42of the guide130. These curved exit tracks172may take on an angulation of approximately 90 degrees, however this angle may be made more acute or obtuse to optimize the positioning of the snare.

In the case of a laparoscopic surgery involving use of a trocar, the guide130may be placed through the tissue layers of the open trocar wound site as shown inFIG. 11. This tissue track may consist of skin160, adipose tissue161, muscle and fascia162and the peritoneum163. Prior to insertion of the guide130through the tissue track, the slider156and plunger153may be pulled into the compressed position to place the arms147in the slender configuration, and the snare loops146in the retracted position. Once the distal barrel tip140of the guide130is appropriately placed posterior to the peritoneal layer163, the slider156and plunger153may be released and spring-biased to the open position, extending the suture snare loops146and expanding the tissue engaging arms147. The guide130may then be retracted until the tissue engaging arms147are resting against the inner peritoneal wall163to align the channels132,136with the appropriate layers of tissue to be sutured.

Once the guide130is secured against the peritoneal wall163, the suture engaging device100, with a first free end section44of suture125engaged, may be inserted through a channel132while carrying the section44of suture125, as shown inFIG. 12. Once the needle100exits the channel132it passes through various layers of tissue162,163and enters the body cavity. As it enters the body cavity, the needle100passes through the snare loop146. The needle100may release the strand of suture125and be removed from the body leaving the suture section44loosely inside the expanded snare loop146. Thus, the suture section44is carried into the body cavity to a point where the suture section44intersects and traverses the generally planar opening48(seeFIG. 11) defined by the expanded snare loop46.

The second free end section46of suture125may then be engaged by the suture engaging device100, and inserted through the opposing channel136to place the second end suture section46. As shown inFIGS. 13A-13B, once the needle100exits the channel136it passes through various layers of tissue162,163and enters the body cavity. As it enters the body cavity, the needle100passes through the opposing snare loop146. The needle100may release the strand of suture125and be removed from the body leaving the suture sections44,46within the boundaries of the respective snare loops146.

FIG. 13Cshows the snare loops146retracted so as to capture the suture sections44,46, which is the configuration actuated inFIG. 6Bwhen the slider156is moved proximally with respect to the main barrel131. With both suture sections44,46captured, the guide130is ready to be retracted from the tissue track50, carrying the suture sections44,46as shown inFIG. 13D.

FIG. 14illustrates an alternative embodiment including a pouch, or basket,178secured to the snare. The pouch178is positioned below the snare and comprises a floor180as a protective element to prevent the distal tip of the needle100from extending deeper into the abdominal cavity. The pouch may be constructed of a compliant fabric, rigid polymer, or other such material to obstruct needle penetration.

InFIG. 15a preferred method200is disclosed for closing a surgical wound using a surgical instrumentation system comprising a guide and suture engagement device as described above. It will be appreciated that this method200enables an operator to pass and retrieve the suture using simply a guide and suture engaging device without the need for additional instrumentation or visualization inside the body cavity. The initial step201comprises actuation of the guide into a slender configuration and insertion of the distal tip into the surgical wound. In step202, a securing mechanism, which may comprise living hinges, is radially expanded for engagement with the inner body cavity wall when the guide is retracted, preventing the guide from being pulled out of the wound as well as providing a reference point for the suture placement. Step203comprises the deployment of two snare loops to be used to capture the suture material. It can be appreciated that step202and203may be combined such that they occur simultaneously. It will further be appreciated that steps202and203may occur by default (e.g., through use of springs) upon release of the guide such that the operator may have both hands free to engage other instruments.

Step204comprises engaging and capturing a first section of a suture with a suture capture mechanism disposed at the distal end of a suture engaging device having a shaft. In step205the suture engaging device with secured suture is inserted through a first track of the guide, through various tissue layers, and ultimately ending inside the body cavity as it passes through the first snare loop. Step206comprises releasing the first suture section from the suture engaging device and retracting the device from the body and guide. The first section of the suture may remain inside the body cavity and loosely encapsulated within the boundaries of the expanded first snare loop.

Step207comprises engaging and capturing a second section of the same suture with the suture capture feature on the suture engaging device. In step208, the suture engaging device with secured suture is inserted through a second track of the guide, through various tissue layers, ending inside the body cavity as it passes through the second snare loop. Step209comprises releasing the suture from the suture engaging device and retracting the device from the body and guide while leaving the second section of the suture inside the body cavity and loosely encapsulated within the boundaries of the second snare loop.

In step210, the suture material may be passed through the slots in the channels on the guide to release the suture from the constraint of the channel. Step210comprises retracting the snare loops back against the guide and securing the suture between the outer guide wall and the snare loop. In step211, the guide may be actuated such that the securing mechanism is radially contracted and converting the guide into the slender configuration. It can be appreciated that step210and211may be combined such that they occur simultaneously or seamlessly with a single motion. In step213the guide can be removed from the body cavity with the two captured sections of the suture. Step214comprises releasing the suture from the snare loops on the guide. The procedure may then be completed at step215by forming a single stitch loop to close the surgical wound.

InFIG. 16an alternative method300is illustrated for closing a surgical wound using a surgical instrumentation system by forming a figure eight stitch as opposed to the single stitch method200. In step301a first length of suture is passed into the body at a first location of the wound comprising the same steps201-210as previously described. In step302, the guide is rotated 90 degrees from the initial position in step301. In step303, a second length of suture is passed into the wound at a second location of the wound comprising steps202-214. Step304comprises completing the closing of the wound by forming a stitch loop with each of the suture strands.

InFIG. 17a preferred method400is illustrated for creating pneumoperitoneum for laparoscopic procedures using an insufflation needle. Step401comprises inserting the tip of the needle through the abdominal wall and into a body cavity. This step may also initially require a small incision in the skin to be made prior to insertion of the needle. In step402, a gas line may be connected to the needle. Step403comprises pumping an inert gas through the needle and into the body cavity until an appropriate internal pressure is achieved. Lastly, in step404the needle may be removed from the body and the endoscopic procedure can begin.

InFIG. 18, an alternative embodiment of a guide502may be useful for directing a suture engaging device501through a body wall. The guide502may be particularly useful for the placement of sutures used in closing wounds or openings through body walls made in surgical procedures to access internal body cavities. Accordingly, the guide502preferably comprises two pathways diagonal to each other and oriented to direct a needle apparatus to both a first internal location to carry and release a first end of a suture, and a second internal location to carry and release a second end of a suture. The guide502comprises a proximal end581and a distal end582.

An oblique view of the preferred guide502is shown inFIGS. 19A-19B. The guide502may comprise a monolithic snare504with two suture snare loops507, a shaft section506, and an actuator section505, all integrally formed. A barrel503comprises two channels509,513as shown inFIG. 20a, and a clip510. The barrel503also defines an inner lumen520and two or more window openings512,521. The barrel503preferably comprises two half barrel pieces514,515secured to one another. The half barrel pieces514,515may be identical in geometry. The barrel503, which may be formed by securing the two half barrel pieces514,515together, defines an inner lumen520that extends along an axis A of the guide502, and two or more channels509,513diagonal to the axis A. Each channel509,513is in communication with a corresponding window opening512,521located adjacent to the distal end582. Ultrasonic welding, adhesive bonding, snap leg features, or a clip510, or a number of other means may be used to secure the half barrel pieces514,515together. The two channels509,513preferably formed by the construct of the barrel half pieces514,515, are disposed within the barrel503to guide the suture passing needle501through the tissue to be sutured. The shaft section506of the monolithic snare504may be slidably disposed within the inner lumen520of the barrel503to provide actuation of the suture snare loops507. The snare loops507may traverse within and extend laterally from the window openings512,521.

The tips516of the snare loops507may serve as a landmark indicator, which is used to position the guide502against the internal peritoneal wall. The two suture snare loops507serve the purpose of capturing the suture material after it has been passed through the tissue wall. The actuator section505of the monolithic snare504and tabs508of the barrel503may facilitate the ease of handling of the guide502. Each snare loop507preferably comprises a pre-formed shape with memory characteristics such that the snare loop507consistently takes on the same shape whenever fully expanded.

As the actuator section505and shaft section506translate with respect to the barrel503, the suture snare loops507move between two positions of radially extended shown inFIGS. 19A and 19B, and retracted shown inFIG. 21A. When each snare loop507is in the radially extended configuration, a pre-defined loop, ring, circle or hoop shape preferably extends laterally from the barrel503. In the preferred embodiment, each snare loop507provides a corresponding C-shaped region511(from a side view as shown inFIG. 22A) for a suture passing needle to pass into and drop off the suture. Each region511is concave with respect to the proximal end581of the guide502. In the preferred embodiment, each snare loop507is aligned with a corresponding tab508located directly above. Each snare loop507defines an opening through which the carried suture traverses. In the preferred embodiment having a pair of snare loops507, each snare loop507is preferably spaced 180 degrees apart from the other and disposed distally adjacent to a corresponding channel exit point518.

When the carried suture is released from the suture engaging device, the suture section intersecting the opening of the snare loop507resides loosely until the snare loop507is retracted. When the snare loop507is retracted the suture material becomes trapped between the snare loop507and the wall of the barrel503at the window opening512in the barrel (see, e.g.,FIG. 13C). In this retracted position, the actuator section505is pulled away from the barrel as shown inFIG. 21A. The projecting snares loops507are collapsed as they are withdrawn into the window opening512and further into the inner lumen520of the barrel503. The projecting sections of each snare loop507converge at the distal end to form a rigid tip516that points upwardly and outwardly from the barrel503. The window opening512provides a recess for housing the tip513to allow the tip516from protruding outside the barrel503outer profile when in the retracted position, thus enabling smooth entry of the guide when being placed through the tissue track. As shown inFIG. 21b, the window opening512decreases in size as it extends towards the inner lumen520. The snare tip516has an enlarged size or width that acts as a positive stop in combination with the narrowing window opening512to prevent excess proximal travel (i.e., retraction) of the monolithic snare504within the barrel503.

The monolithic snare504may be constructed from a polymer that can withstand a high degree of strain. The percent of elongation at yield may range from 3-8%. The snare loop507may have thin cross-sections to provide the flexibility to easily bend and conform to various geometric shapes yet stiff enough to create a self-supported snare loop that extends generally perpendicular to the long axis of the guide. The monolithic snare504may also extend laterally in a geometry that from a side view is a continuous radius525as shown inFIG. 22A. The continuous radius525effectively keeps the rigid tip along the “continuous radius” path as the snare loop507is being retracted into the barrel. The ratio of the continuous radius525to the cross sectional geometry of the snare loop507is such that the strain level of the material when retracted and constrained in the barrel503will not cause noticeable permanent deformation of the memorized pre-formed shape when constrained for a duration up to one hour. The same principle is true for the snare radii526,527,528as shown in the top planar view illustrated inFIG. 22B. Materials that may be used to construct the monolithic snare504include plastics such as nylon, polyethylene, polyester or polypropylene.

In this alternative embodiment, the guide502provides two different, diagonal pathways for a suture passing needle apparatus and thus comprises first and second channels509,513as more clearly shown inFIG. 20A. The channels509,513are directionally diagonal to the long axis A of the guide502at some acute angle, preferably in the range of 5-30 degrees. The angle of the channels509,513controls the depth of bite into the tissue, such that a greater angle provides a greater bite of tissue. Angular spacing between entries to the channels509,513are preferably equal (i.e., equiangular) depending upon the number of channels, e.g., 180 degrees apart if there are two channels, 120 degrees apart if there are three channels, etc. Therefore, channel exits are also preferably equiangular. Two separate entry points521,522are provided on the channels509,513for a suture passing needle to enter the guide502, as well as two separate exit points518,523. Each channel509,513, has a corresponding slot512,524, or opening that allows for a strand of suture to be removed from the channel. This may be necessary to complete the suture loop in the tissue. As shown inFIGS. 20A-B, the proximal section of each channel509,513, may have a wider mouth including a tapered section517that enables angulation of the suture passing needle501, such that a lesser angle allows a lesser bite of tissue.

The actuation section505of the monolithic snare504may have a locking leg519that snap fits into a latch529in the barrel503as shown inFIG. 23. The locking leg519can be depressed to flex from the “locked” position to enable movement of the monolithic snare504. The actuation section505may also include a variety of other connectors to facilitate a releasable locking connection between the monolithic snare504and the barrel503.

In another embodiment shown inFIG. 24, the guide530comprises a barrel531with indicia and a monolithic snare532with a ring-shaped actuation section533for easy manipulation of the monolithic snare532. The guide530includes two indicators to facilitate deployment; 1) a line mark535on an outer barrel surface583, and 2) a lateral tip536of each snare loops534. The two indicators can be employed in a method to accommodate proper positioning of the guide530in various abdominal wall thicknesses to achieve predictable suture placement in the tissue.

In the case of a laparoscopic surgery involving use of a trocar, the guide530may be placed through the tissue layers of the open trocar wound site as shown inFIGS. 25A and 25B. This tissue track in the abdominal wall may include skin537, adipose tissue538, muscle and fascia539and the peritoneum540. Prior to insertion of the guide530through the tissue track, the actuator section533may be pulled away from the barrel530in a proximal direction, moving the snare loops534into the fully retracted position to achieve the most slender profile. Once the distal end of the guide530is appropriately placed posterior to the peritoneal layer540, the actuator section533may be pushed toward the barrel531, extending the suture snare loops534. The guide530may then be refracted until the lateral tips536are resting against the inner peritoneal wall540to align the channels with the appropriate layers of tissue to be sutured, as shown inFIG. 25a.

Once the guide530is secured against the peritoneal wall540, the suture engaging device501, with a first free end section542of suture542engaged, may be inserted through a first channel544while carrying the first section542of suture541, as shown inFIG. 25A. Once the needle551exits the channel544it passes through various layers of tissue539,540, and enters the body cavity570. As it enters the body cavity570, the needle551passes through the first snare loop534. The needle551may release the strand of suture541and be removed from the body leaving the suture section542loosely inside the expanded first snare loop534. Thus, the suture section542is carried into the body cavity to a point where the suture section542intersects and traverses the generally planar opening defined by the expanded first snare loop534.

The second free end section of suture541may then be engaged by the same suture engaging device501, and inserted through the opposing second channel to place the second end suture section543. Once the needle551exits the opposing second channel it passes through various layers of tissue539,540and enters the body cavity570. As it enters the body cavity570, the needle551passes through the opposing second snare loop534. The needle551may release the second strand of suture541and be removed from the body leaving the suture sections542,543within the boundaries of the respective snare loops534.

Moving the actuator section533away from the barrel retracts the snare loops534so as to capture the suture sections542,543. With both suture sections542,543captured, the guide530is refracted from the tissue track, carrying the suture sections542,543. With the guide530and suture sections542,543exposed outside the body cavity, the actuator section533can be pushed toward the barrel531extending the suture snare loops534, and thus releasing the suture sections542,543. A knot can then be tied in the suture sections542,543and secured to provide closure of the wound.

FIG. 25Bshows the placement of the needle501piercing through the tissue. The distance545from the puncture location of the needle501through the peritoneum540to the closest edge, or perimeter, of the defect, which coincides with the sidewall of the barrel, is desirable to be nominally 8 mm. With the guide530positioned perpendicular to the skin surface and the lateral tips536resting against the inner peritoneal wall540, the channels544are aligned to guide the needle551through the desirable amount of tissue to be sutured. However, for this method, the abdominal wall thickness546must be at an adequate thickness to assure the needle551will exit the channel544below the skin537. It is undesirable to have the suture541through the skin537.

FIG. 26shows an abdominal wall thickness547, where for the above described method of positioning the lateral tips536resting against the peritoneal wall540with the guide perpendicular to the skin surface, the thickness is not adequate. The needle is shown with a puncture548through the skin537. The guide530needs to be inserted further into the wound for the needle551to avoid piercing the skin537—namely, for the needle551to exit the guide530subcutaneously. An indicator in the form of a line mark535is provide on the outer surface of the barrel531as a reference. When the line mark535is positioned below the skin surface537, the exit of the channel544will be below the skin surface537such that the needle551will not pierce through the skin537.FIG. 27Ashows the guide530inserted further in the wound, where the line mark535is below the skin surface and thus no longer visible. This results in the lateral tips536being a significant distance548away from the peritoneum540.FIG. 27Bshows the placement of the needle501piercing through the tissue. The relatively shorter distance545from the puncture location of the needle501through the peritoneum549to the edge of the defect, which coincides with the sidewall of the barrel, may not be desirable in such thinner abdominal walls.

An alternative method can be used to achieve a desirable placement of the needle551and suture541through the tissue.FIG. 28Ashows the guide530positioned in a relatively thinner abdominal wall thickness547as described above.FIG. 28Bshows the line mark535below the skin537.FIG. 28cshows the lateral tip536a vertical distance548from the peritoneum540. Prior to the placing the needle551though the tissue539,540, the lateral tip536may be used as a landmark while tilting the guide530at an angle to the primary guide axis560, until the first lateral tip536comes in close proximity to or abuts the peritoneum540, as shown inFIG. 29. The tissue area562will compress, and placement of the needle551will encompassed a greater amount of tissue539,540.

With the tilted guide530in position, the suture engaging device501, with a first free end section542of suture542engaged, may be inserted through a first channel544while carrying the section542of suture541. Once the needle551exits the channel544it passes through the compressed layers of tissue539,540, and enters the body cavity. As it enters the body cavity, the needle551passes through the first snare loop534. The needle551may release the strand of suture541and be removed from the body leaving the suture section542loosely inside the expanded snare loop534. Thus, the first suture section542is carried into the body cavity to a point where the first suture section542intersects and traverses the generally planar opening defined by the expanded snare loop534.

The guide530is then tilted in the opposite direction, such that the opposite second lateral tip536of the second snare loop534comes in close proximity to the peritoneum540. With the tilted guide530in position, the second free end section of suture541may then be engaged by the suture engaging device501, and inserted through the opposing channel to place the second end suture section543. Once the needle551exits the opposing channel it passes through the compressed layers of tissue539,540and enters the body cavity. As it enters the body cavity, the needle551passes through the opposing second snare loop534. The needle551may release the strand of suture541and be removed from the body leaving the suture sections542,543within the boundaries of the respective snare loops534.

By tilting the guide530such that the lateral tip536of each receiving snare loop534comes into contact with the adjacent peritoneum540, a greater and more desirable horizontal distance, or “bite,” is achieved between each puncture location of the needle501through the peritoneum540to the closest edge of the defect coinciding with the sidewall of the barrel.

Moving the actuator section533away from the barrel retracts the snare loops534so as to capture the suture sections542,543. With both suture sections542,543captured, the guide530is refracted from the tissue track, carrying the suture sections542,543. With the guide530and suture sections542,543exposed outside the body cavity, the actuator section533can be pushed toward the barrel531extending the suture snare loops534, and thus releasing the suture sections542,543. A knot can then be tied in the suture sections542,543and secured to provide closure of the wound.

FIG. 30illustrates a preferred method600for closing a surgical wound using suture. Step610comprises actuating a guide into a slender configuration for insertion into a body cavity by retracting a monolithic snare. Step620comprises translating the monolithic snare distally with respect to a barrel to deploy at least two suture snare loops so as to radially expand a securing mechanism against an internal wall of the body cavity

If a thinner abdominal wall is involved, then optional step630may be employed by tilting the guide in a first direction to cause a distal tip of a first snare loop to approach or abut an inner peritoneal wall.

Step640comprises engaging a first section of suture with a suture engaging device, inserting the suture engaging device into a first channel of a guide, releasing the first section of suture in the body cavity and retracting the device from the first channel.

Again, if a thinner abdominal wall is involved, then optional step650may be employed by tilting the guide in a second direction opposite the first direction to cause a distal tip of a second snare loop to approach or abut the inner peritoneal wall.

Step660comprises engaging a second section of suture with the suture engaging device, inserting the suture engaging device into a second channel of the guide, releasing the second section of suture in the body cavity at an equiangular spacing from the released first section of suture, and retracting the device from the second channel. In a preferred embodiment where only two snare loops are provided, then the channel exits and associated snare loops are positioned 180 degrees from each other.

Step670comprises actuating the monolithic snare to retract the snare loops and secure the first and second sections of suture while forming a slender configuration of the guide. Step670may simply involve translating the actuation section in a proximal direction with respect to the barrel.

Step680comprises retracting the guide in the slender configuration with the captured suture from the body.

This method600may also comprise rotating the guide and repeating steps610through680to form as many stitch loops as desired.

Insubstantial changes from the claimed subject matter as viewed by a person with ordinary skill in the art, now known or later devised, are expressly contemplated as being equivalently within the scope of the claims. Therefore, obvious substitutions now or later known to one with ordinary skill in the art are defined to be within the scope of the defined elements. The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptually equivalent, what can be obviously substituted and also what incorporates the essential idea of the invention.