Methods and devices for sealing stapled tissue

Adjunct material and methods of using adjunct material to reinforce a staple line are provided herein. In general, adjunct material can be used to maintain a seal in tissue and prevent stapled tissue from tearing. This adjunct material can be coupled to a jaw of a surgical stapler, and can be deployed into tissue along with the staples. In some embodiments, the adjunct material can be sized and shaped so that a portion of the material extends laterally outside of the staple line and distributes strain to tissue outside of the staple line. In certain aspects, sealant can be applied to the staple line and to the adjunct material in various ways to further seal the tissue and/or prevent leaks from forming in the tissue.

FIELD

The subject matter disclosed herein relates to methods and devices for reinforcing a staple line.

BACKGROUND

Surgical staplers are used in surgical procedures to seal, divide, and/or transect tissues in the body by closing openings in tissue, blood vessels, ducts, shunts, or other objects or body parts involved in the particular procedure. The openings can be naturally occurring, such as passageways in blood vessels, airways or an internal lumen or organ like the stomach, or they can be formed by the surgeon during a surgical procedure, such as by puncturing tissue or blood vessels to form a bypass or an anastomosis, or by cutting tissue during a stapling procedure.

Most staplers have a handle with an elongate flexible or rigid shaft having a pair of opposed jaws formed on an end thereof for holding and forming staples therebetween. At least one of the opposed jaws is movable relative to the other jaw. In the case of laparoscopic surgery, often one jaw is fixed and the other is movable. In some devices (for example an open linear stapler), the opposed jaws can be separated by the operator and reassembled providing the relative motion needed for tissue placement. The staples are typically contained in a staple cartridge, which can house multiple rows of staples and is often disposed in one of the two jaws for ejection of the staples to the surgical site. In use, the jaws are positioned so that the object to be stapled is disposed between the jaws, and staples are ejected and formed when the jaws are closed and the device is actuated. Some staplers include a knife configured to travel between rows of staples in the staple cartridge to longitudinally cut the stapled tissue between the stapled rows. Placement of the device, manipulation of components or systems of the device, and other actuations of the device such as articulation, firing, etc. can be accomplished in a variety of ways, such as electromechanically, mechanically, or hydraulically.

While surgical staplers have improved over the years, a number of problems can potentially arise. Although rare, as illustrated inFIG. 1, one problem is that leaks can occur due to staples S forming tears H when penetrating a tissue T or other object in which the staples S are disposed. Blood, air, gastrointestinal fluids, and other fluids can seep through the tears H formed by the staples S, even after the staples S are fully formed. The tissue T being treated can also become inflamed due to the manipulations and deformations that can occur during stapling. Still further, staples, as well as other objects and materials implanted during stapling procedures, generally lack the same characteristics as tissue in which they are implanted. For example, staples and other objects and materials can lack the natural flexibility of the tissue in which they are implanted. A person skilled in the art will recognize that it is often desirable for tissue to maintain as much of its natural characteristics as possible after staples are disposed therein.

Accordingly, there remains a need for methods and devices for reinforcing a staple line.

SUMMARY

Methods for implanting a tissue reinforcement material onto tissue are provided. The method can include engaging tissue between a cartridge assembly and an anvil of a surgical stapler at a surgical site, at least one of the cartridge assembly and the anvil having a tissue reinforcement material retained thereon. The tissue reinforcement material can include a central region configured to provide a seal around a staple penetration site (e.g. in the tissue, in the central region, etc.) and an outer region adjacent to the central region and defining an edge of the tissue reinforcement material. Actuating the surgical stapler can eject staples from the cartridge assembly so as to form a staple line through the central region and into the tissue to hold the tissue reinforcement material at the surgical site. After actuating the surgical stapler, sealant can be delivered to the tissue reinforcement material when the sealant is in a first, liquid state such that the sealant solidifies thereon and reinforces a seal of the tissue at the staple line.

The method can vary in any number of ways. In certain aspects, actuating the surgical stapler ejects the staples through the central region of the tissue reinforcement material. The method can further include inserting the cartridge assembly and the anvil into the surgical site with the outer region of the tissue reinforcement material folded around at least one of the cartridge assembly and the anvil. Actuating the surgical stapler can release the tissue reinforcement material from the surgical stapler. In certain aspects, the surgical stapler advances the cutting member through the central region of the tissue reinforcement material. In other aspects, the surgical stapler forms a staple line having at least two rows of staples.

The sealant can be delivered to tissue in various ways. In certain aspects, the sealant is delivered through an applicator tool positioned adjacent to the tissue reinforcement material. Delivering the sealant can include depositing the sealant onto both the central and outer regions of the reinforcement material. In certain aspects, the sealant is delivered to the tissue reinforcement material in the first, liquid state, and the sealant penetrates a space in the tissue at the staple line and solidifies therein.

Systems for reinforcing a tissue seal are also provided. The system can include a sealant, a container, and an applicator tool. The sealant can be configured to transition from a first liquid state to a second solid state. The container can be configured to retain the sealant therein when the sealant is in the first liquid state, the container having a first port for receiving a gas and a second port for outputting nebulized sealant. The applicator tool can be coupled to the second port of the container, the applicator tool being configured to deliver the nebulized sealant to a surgical site.

The system can vary in any number of ways. In certain aspects, the applicator tool is a trocar. In other aspects, the gas includes carbon dioxide. In other aspects, the sealant includes a mixture of collagen, fibrinogen, and thrombin. These biologic materials may be derived from human and/or animal sources. The sealant can be configured to transition from the first liquid state to the second solid state after a predetermined amount of time. The system can include additional components. For example, a first tube can extend between the second port of the container and the applicator for receiving nebulized sealant.

Methods for delivering sealant to a body of a patient are also provided. The method can include delivering gas to a container having a sealant retained therein, thereby transitioning the sealant from a first, liquid state to a second, nebulized state. The nebulized sealant can be delivered through an applicator tool extending through an access port in a patient, the nebulized sealant solidifying onto tissue and forming a seal thereon.

The method can be performed in various ways. For example, the applicator tool can be positioned in a thoracic cavity of a patient prior to delivering the gas to the container. In certain aspects, the applicator tool includes a trocar, and nebulized sealant is delivered directly through the trocar and into the patient. The method can include positioning a distal end of the applicator tool adjacent to a staple line in the tissue prior to delivering the nebulized sealant to the tissue. In certain aspects, the hardened sealant is absorbed into the body after a predetermined passage of time.

DETAILED DESCRIPTION

It can be desirable to use one or more biologic materials and/or synthetic materials, collectively referred to herein as “adjunct materials,” in conjunction with surgical instruments to help improve surgical procedures. These biologic materials may be derived from human and/or animal sources. A person skilled in the art may refer to these types of materials as buttress materials as well as adjunct materials.

Various exemplary devices and methods are provided for performing surgical procedures. In some embodiments, the devices and methods are provided for open surgical procedures, and in other embodiments, the devices and methods are provided for laparoscopic, endoscopic, and other minimally invasive surgical procedures. The devices may be fired directly by a human user or remotely under the direct control of a robot or similar manipulation tool. However, a person skilled in the art will appreciate that the various methods and devices disclosed herein can be used in numerous surgical procedures and applications. Those skilled in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, or through an access device, such as a trocar cannula. For example, the working portions or end effector portions of the instruments can be inserted directly into a patient's body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced.

End effectors of the surgical instruments as described herein can be configured to deliver one or more synthetic materials and/or biologic materials, collectively referred to herein as “adjunct materials,” to a surgical site to help improve surgical procedures. These biologic materials may be derived from human and/or animal sources. While a variety of different end effectors can benefit from the use of adjunct materials, in some exemplary embodiments the end effector can be a surgical stapler. When used in conjunction with a surgical stapler, the adjunct material(s) can be disposed between and/or on jaws of the stapler, incorporated into a staple cartridge disposed in the jaws, or otherwise placed in proximity to the staples. When staples are deployed, the adjunct material(s) can remain at the treatment site with the staples, in turn providing a number of benefits. In some instances, the adjunct material(s) can be used to help seal holes formed by staples as they are implanted into tissue, blood vessels, and various other objects or body parts, and/or can be used to provide tissue reinforcement at the treatment site. Tissue reinforcement may be needed to keep the staples from tearing through the tissue if the tissue is diseased, is healing from another treatment such as irradiation, medications such as chemotherapy, or other tissue property altering situation. In some instances, the adjunct material(s) may minimize tissue movement in and around the staple puncture sites that can occur from tissue deformation that occurs after stapling (e.g., lung inflation, gastrointestinal tract distension, etc.). It will be recognized by one skilled in the art that a staple puncture site may serve as a stress concentration and that the size of the hole created by the staple will grow when the tissue around it is placed under tension. Restricting the tissue's movement around these puncture sites can minimize the size the holes may grow to under tension. In some instances, the adjunct material(s) can be configured to wick or absorb beneficial fluids, e.g., sealants, blood, glues, that further promote healing, and in some instances, the adjunct material(s) can be configured to degrade to form a gel, e.g., a sealant, that further promotes healing. In some instances, the adjunct may carry materials that when placed into a wet environment (e.g., blood, water, saline, or other bodily fluids) form a sealant to create a seal (e.g., human or animal derived fibrinogen and thrombin can be lyophilized into a powder form that when mixed with water creates a sealant). Still further, the material(s) can help reduce inflammation, promote cell growth, and otherwise improve healing.

FIG. 2illustrates one embodiment of an adjunct material that includes a porous buttress30that can be fixed to a tissue T to be treated by a surgical stapler and that remains at the treatment site with staples70. The buttress30can be made from one or more absorbent materials and can be stamped, pressed, cut, molded, woven, melted, blown, comprised from composite structures and/or methods or otherwise shaped to facilitate absorption, reinforcement, delivery and/or retention of beneficial fluids such as sealants, glues, blood, etc. The absorption and/or retention of beneficial fluids, for example a fibrin sealant40, at the treatment site can further help to prevent leaks and to reinforce the buttress30.

Surgical Stapling Instrument

While a variety of surgical instruments can be used in conjunction with the adjunct materials disclosed herein,FIG. 3illustrates one, non-limiting exemplary embodiment of a surgical stapler10suitable for use with one or more adjunct materials. The instrument10generally includes a handle assembly12, a shaft14extending distally from a distal end12dof the handle assembly12, and an end effector50at a distal end14dof the shaft14. Because the illustrated embodiment is a surgical stapler, the end effector50has jaws52,54, although other types of end effectors can be used with the shaft14, handle assembly12, and components associated with the same. The surgical stapler10includes opposed lower and upper jaws52,54with the lower jaw52including a staple channel56(FIG. 4) configured to support a staple cartridge60, and the upper jaw54having an inner surface58that faces the lower jaw52and that is configured to operate as an anvil to help deploy staples70of the staple cartridge60. The jaws52,54are configured to move relative to one another to clamp tissue or other objects disposed therebetween, and components of a firing system can be configured to pass through at least a portion of the end effector50to eject the staples into the clamped tissue. In various embodiments a knife blade81can be associated with the firing system to cut tissue during the stapling procedure. At least one of the opposed lower and upper jaws52,54will be moveable relative to the other lower and upper jaws52,54. At least one of the opposed lower and upper jaws52,54may be fixed or otherwise immovable. In some embodiments, both of the opposed lower and upper jaws52,54will be movable.

Operation of the end effector50can begin with input from a clinician at the handle assembly12. The handle assembly12can have many different configurations designed to manipulate and operate the end effector50associated therewith. In the illustrated embodiment, the handle assembly12has a pistol-grip type housing18with a variety of mechanical and/or electrical components disposed therein to operate various features of the instrument. For example, the handle assembly12can include a rotation knob26mounted adjacent a distal end12dthereof which can facilitate rotation of the shaft14and/or the end effector50with respect to the handle assembly12about a longitudinal axis L of the shaft14. The handle assembly12can further include clamping components as part of a clamping system actuated by a clamping trigger22and firing components as part of the firing system that are actuated by a firing trigger24. The clamping and firing triggers22,24can be biased to an open position with respect to a stationary handle20, for instance by a torsion spring. Movement of the clamping trigger22toward the stationary handle20can actuate the clamping system, described below, which can cause the jaws52,54to collapse towards each other and to thereby clamp tissue therebetween. Movement of the firing trigger24can actuate the firing system, described below, which can cause the ejection of staples from a staple cartridge disposed therein and/or the advancement the knife blade81to sever tissue captured between the jaws52,54. A person skilled in the art will recognize that various configurations of components for a firing system, mechanical, hydraulic, pneumatic, electromechanical, robotic, or otherwise, can be used to eject staples and/or cut tissue, and thus a detailed explanation of the same is unnecessary.

As shown in more detail inFIG. 4, the end effector50of the illustrated embodiment is a surgical stapling tool having a lower jaw52that serves as a cartridge assembly or carrier and an opposed upper jaw54that serves as an anvil. The staple cartridge60, having a plurality of staples70therein, is supported in a staple tray57, which in turn is supported within the cartridge channel of the lower jaw52. The upper jaw54has a plurality of staple forming pockets366(FIG. 11), each of which is positioned above a corresponding staple from the plurality of staples370a,370bcontained within the staple cartridge60. The upper jaw54can be connected to the lower jaw52in a variety of ways, although in the illustrated embodiment the upper jaw54has a proximal pivoting end54pthat is pivotally received within a proximal end56pof the staple channel56, just distal to its engagement to the shaft14. When the upper jaw54is pivoted downwardly, the upper jaw54moves the anvil surface58and the staple forming pockets366formed thereon move toward the opposing staple cartridge60.

Various clamping components can be used to effect opening and closing of the jaws52,54to selectively clamp tissue therebetween. In the illustrated embodiment, the pivoting end54pof the upper jaw54includes a closure feature54cdistal to its pivotal attachment with the staple channel56. Thus, a closure tube82, whose distal end includes a horseshoe aperture82athat engages the closure feature54c, selectively imparts an opening motion to the upper jaw54during proximal longitudinal motion and a closing motion to the upper jaw54during distal longitudinal motion of the closure tube82in response to the clamping trigger22. It will be appreciated by a person skilled in the art that opening and closure of the end effector50may be effected by relative motion of the lower jaw52with respect to the upper jaw54, relative motion of the upper jaw54with respect to the lower jaw52, or by motion of both jaws52,54with respect to one another.

The firing components of the illustrated embodiment can include a firing bar84, as shown inFIG. 5, having an E-beam86on a distal end thereof. The firing bar84is encompassed within the shaft14, for example in a longitudinal firing bar slot14sof the shaft14, and guided by a firing motion from the handle12. Actuation of the firing trigger24can affect distal motion of the E-beam86through at least a portion of the end effector50to thereby cause the firing of staples70contained within the staple cartridge60. In the illustrated embodiment, guides85projecting from a distal end of the E-Beam86can engage a wedge sled90, which in turn can push staple drivers92upwardly through staple cavities68formed in the staple cartridge60. Upward movement of the staple drivers92applies an upward force on each of the plurality of staples70within the cartridge60to thereby push the staples70upwardly against the anvil surface58of the upper jaw54and to create formed staples70′.

In addition to causing the firing of staples, the E-beam86can be configured to facilitate closure of the jaws52,54, spacing of the upper jaw54from the staple cartridge60, and/or severing of tissue captured between the jaws52,54. In particular, a pair of top pins87and a pair of bottom pins89can engage one or both of the upper and lower jaws52,54to compress the jaws52,54toward one another as the firing bar84advances through the end effector50. Simultaneously, a knife81extending between the top and bottom pins87,89can be configured to sever tissue captured between the jaws52,54.

In use, the surgical stapler10can be disposed in a cannula or port and disposed at a surgical site. A tissue to be cut and stapled can be placed between the jaws52,54of the surgical stapler10. Features of the stapler10can be maneuvered as desired by the clinician to achieve a desired location of the jaws52,54at the surgical site and the tissue with respect to the jaws52,54. After appropriate positioning has been achieved, the clamping trigger22can be pulled toward the stationary handle20to actuate the clamping system. The trigger22can cause components of the clamping system to operate such that the closure tube82advances distally through at least a portion of the shaft14to cause at least one of the jaws52,54to collapse towards the other to clamp the tissue disposed therebetween. Thereafter, the trigger24can be pulled toward the stationary handle20to cause components of the firing system to operate such that the firing bar84and/or the E-beam86are advanced distally through at least a portion of the end effector50to effect the firing of staples70and optionally to sever the tissue captured between the jaws52,54.

Another embodiment of a surgical instrument100is illustrated inFIG. 6. Like surgical instrument10, surgical instrument100includes a handle assembly112with a shaft114extending distally therefrom and having an end effector150on a distal end thereof for treating tissue. Upper and lower jaws154,152of the end effector150can be configured to capture tissue therebetween, staple the tissue by firing of staples from a cartridge160disposed in the lower jaw154, and/or to create an incision in the tissue. In this embodiment, an attachment portion116on a proximal end of the shaft114can be configured to allow for removable attachment of the shaft114and the end effector150to the handle assembly112. In particular, mating features125of the attachment portion116can mate to complementary mating features123at a distal end112dof the handle assembly112. The mating features123,125can be configured to couple together via, e.g., a snap fit coupling, a bayonet type coupling, etc., although any number of complementary mating features and any type of coupling can be used to removably couple the shaft114to the handle assembly112. Although the entire shaft114of the illustrated embodiment is configured to be detachable from the handle assembly112, in some embodiments the attachment portion116can be configured to allow for detachment of only a distal portion of the shaft114. Detachable coupling of the shaft114and/or the end effector150can allow for selective attachment of a desired end effector150for a particular procedure, and/or for reuse of the handle assembly112for multiple different procedures.

The handle assembly112can have one or more features thereon to manipulate and operate the end effector150. By way of non-limiting example, a rotation knob126mounted on a distal end of the handle assembly112can facilitate rotation of the shaft114and/or the end effector150with respect to the handle assembly112. The handle assembly112can further include clamping components as part of a clamping system actuated by trigger122and firing components as part of a firing system that can also be actuated by the trigger122. Thus, in some embodiments, movement of the trigger122toward a stationary handle120through a first range of motion can actuate clamping components to cause opposed jaws152,154to approximate toward one another to a closed position. Further movement of the trigger122toward the stationary handle120through a second range of motion can actuate firing components to cause the ejection of staples from the staple cartridge160and/or the advancement of a knife to sever tissue captured between the jaws152,154.

Yet another embodiment of a surgical instrument200is illustrated inFIG. 7. Like surgical instruments10and100, surgical instrument200includes a handle assembly212with a shaft214extending distally therefrom and having an end effector250on a distal end thereof for treating tissue. The end effector250can include a cartridge assembly252and an anvil254, each having a tissue-contacting surface260p,260dthat is substantially circular in shape. The cartridge assembly252and anvil254can be coupled together via a shaft262extending from the anvil254to the handle assembly212of the stapler200, and manipulating an actuator222on the handle assembly212can retract and advance the shaft262to move the anvil254relative to the cartridge assembly252. In one embodiment, the shaft262can be formed of first and second portions (not shown) configured to releasably couple together to allow the anvil254to be detached from the cartridge assembly252, allowing greater flexibility in positioning the anvil254and the cartridge assembly252in a body. For example, the first portion of the shaft can be disposed within the cartridge assembly252and extend distally outside of the cartridge assembly252, terminating in a distal mating feature. The second portion of the shaft214can be disposed within the anvil254and extend proximally outside of the cartridge assembly252, terminating in a proximal mating feature. In use, the proximal and distal mating features can be coupled together to allow the anvil254and cartridge assembly252to move relative to one another. The anvil254and cartridge assembly252can perform various functions and can be configured to capture tissue therebetween, staple the tissue by firing of staples from a cartridge assembly252and/or can create an incision in the tissue. In general, the cartridge assembly252can house a cartridge containing the staples and can deploy staples against the anvil254to form a circular pattern of staples around a circumference of a tubular body organ.

The handle assembly212of the stapler200can have various actuators disposed thereon that can control movement of the stapler. For example, the handle assembly212can have a rotation knob226disposed thereon to facilitate positioning of the end effector250via rotation, and/or a trigger222for actuation of the end effector250. Movement of the trigger222through a first range of motion can actuate components of a clamping system to approximate the jaws, i.e. move the anvil254toward the cartridge assembly252. Movement of the trigger222through a second range of motion can actuate components of a firing system to cause the staples to deploy from the staple cartridge assembly252and/or cause advancement of a knife to sever tissue captured between the cartridge assembly252and the anvil254.

The illustrated embodiments of surgical stapling instruments10,100, and200provide only a few examples of many different configurations, and associated methods of use, that can be used in conjunction with the disclosures provided herein. Although the illustrated embodiments are all configured for use in minimally invasive procedures, it will be appreciated that instruments configured for use in open surgical procedures, e.g., open linear staplers as described in U.S. Pat. No. 8,317,070, can be used in conjunction with the disclosures provided herein. Greater detail on the illustrated embodiments, as well as additional exemplary embodiments of surgical staplers, components thereof, and their related methods of use, that can be used in accordance with the present disclosure include those devices, components, and methods provided for in U.S. Publication No. 2013/0256377, U.S. Pat. Nos. 8,393,514, 8,317,070, 7,143,925, U.S. patent application Ser. No. 14/074,884, entitled “Sealing Materials for Use in Surgical Procedures, and filed on Nov. 8, 2013, U.S. patent application Ser. No. 14/074,810, entitled “Hybrid Adjunct Materials for Use in Surgical Stapling,” and filed on Nov. 8, 2013, U.S. patent application Ser. No. 14/075,438, entitled “Positively Charged Implantable Materials and Method of Forming the Same,” and filed on Nov. 8, 2013, U.S. patent application Ser. No. 14/075,459, entitled “Tissue Ingrowth Materials and Method of Using the Same,” and filed on Nov. 8, 2013, U.S. patent application Ser. No. 14/074,902, entitled “Hybrid Adjunct Materials for Use in Surgical Stapling,” and filed on Nov. 8, 2013, U.S. patent application Ser. No. 14/226,142, entitled “Surgical Instrument Comprising a Sensor System,” and filed on Mar. 26, 2014, each of which is incorporated by reference herein in its entirety.

End Effector Variations

End effectors of the surgical stapling instruments described herein can have one or more features for adjusting an amount of compression applied to tissue captured by the end effector. In some embodiments, the end effector can be configured to create a desired compression profile in tissue captured therein, for example a profile that helps to minimize bleeding, tearing, and/or leakage of the treated tissue. By way of non-limiting example, the desired tissue compression profile can be obtained using variations in a gap between upper and lower jaws of the end effector and/or variations in the orientation, size, and/or shape of staples applied to tissue by the end effector. As described in detail herein, adjunct material(s) used in conjunction with such an end effector can be configured to assist in creating the desired tissue compression profile and/or to accommodate features used to create the desired tissue compression profile.

Any such variations described herein can be used alone or together to provide the desired tissue compression profile. Although exemplary end effectors and components thereof are described in conjunction with a particular surgical instrument, e.g., instruments10,100, and200, it will be appreciated that the end effectors and components thereof can be configured for use with other embodiments of surgical instruments as described herein.

In some embodiments, a staple cartridge disposed within an end effector of a surgical stapling instrument can have a first portion configured to compress tissue captured by the end effector more than a second portion when the end effector is in a closed position. The first portion of the cartridge can be spaced longitudinally and/or laterally from the second portion to create a desired compression gradient. For example, as shown inFIGS. 4 and 8, the staple cartridge60can have a stepped tissue contacting surface. In particular, the cartridge60can have an inner tissue contacting surface62and outer tissue contacting surfaces64that extend upwardly to a taller height than the inner tissue contacting surface62. In this way, when the upper jaw54is in the closed position in close approximation with the cartridge60, the anvil surface58can be configured to compress the outer surfaces64more than the inner surface62due to the taller height of the outer surfaces64. In some circumstances, including circumstances where tissue positioned between the anvil surface58and the cartridge60has a constant, or at least substantially constant, thickness, the pressure generated within the tissue can be greater at outer portions of the end effector50than at inner portions of the end effector50. Whereas a compression gradient generated by the cartridge60varies in a stepped manner, it will be appreciated by a person skilled in the art that a gradual compression gradient can be generated within the tissue by a gradual increase in height of various portions of the cartridge60. It will also be appreciated that a compression gradient can be obtained by variations in height of the anvil surface58, alone or in combination with height variations of the cartridge60, and that height variations can be spaced laterally and/or longitudinally across the end effector50.

In some embodiments, one or more adjunct materials fixed to an end effector of a surgical stapling instrument can be used to create a desired compression profile in tissue captured by the end effector. Referring now toFIG. 9, a compressible, implantable staple cartridge360can be formed from one or more adjunct materials as described herein and can be configured to be seated within an end effector of a surgical instrument, e.g., an end effector350. The cartridge360can have a height that decreases from a tallest height H1at a distal end360dthereof to a smallest height H2at a proximal end360pthereof. In this way, when an upper jaw354of the end effector350is in the closed position in close approximation with the cartridge360, an upper jaw354of the end effector350can be configured to compress the distal end360dmore than the proximal end360p. Although the compression gradient created in the captured tissue by the cartridge360decreases linearly from the distal end360dto the proximal end360p, it will appreciated by a person skilled in the art that any compression gradient can be created by different shapes of the cartridge360. In at least one embodiment, a thickness of the cartridge360can vary across its width, similar to the cartridge360.

In some embodiments, staples contained within a staple cartridge of an end effector can be configured to create a desired compression profile within tissue captured by the staples. The desired compression profile can be created in stapled tissue, for example, where staples within the staple cartridge have different unformed staple heights. As shown inFIG. 10, an unformed height H of the exemplary staple70can be measured from a base74of the staple70to a top, or tip, of legs72a,72bof the staple70. Referring now toFIG. 11, which illustrates a cross section of the end effector350, a first group of staples370acan have first staple height H1that is taller than a second staple height H2of a second group of staples370b. The first group of the staples370acan be positioned in a first portion of the staple cartridge360, for example in an outer portion, and the second group of staples370bcan be positioned in a second portion of the staple cartridge360, for example in an inner portion. In the illustrated embodiment, the cartridge360, and therefore the compression gradient, can be configured to be symmetrical about a slot367configured to receive a cutting instrument, e.g., the E-beam86, therethrough. It will be appreciated by a person skilled in the art that the first and second groups of staples370a,370bcan be arranged in any pattern and can be spaced laterally and/or longitudinally along the cartridge360. In certain embodiments, a plurality of staple groups, each group having different unformed staple heights, can be utilized. In at least one such embodiment, a third group having an intermediate staple height can be positioned in the cartridge intermediate the first group of staples and the second group of staples. In various embodiments, each staple within a staple row in the staple cartridge can comprise a different staple height. In at least one embodiment, the tallest staple within a staple row can be positioned on a first end of a staple row and the shortest staple can be positioned on an opposite end of the staple row. In at least one such embodiment, the staples positioned intermediate the tallest staple and the shortest staple can be arranged such that the staple heights descend between the tallest staple and the shortest staple, for example.

Similarly, staples within a staple cartridge can have different crown widths to create a desired compression profile in the stapled tissue. As shown inFIG. 10, a crown width W of the exemplary staple70can be measured from one side of the base74of the staple70to an opposite side. Like the above-described variations in staple height H, variations in the staple width W can be spaced throughout the staple cartridge to create a plurality of staple groups dispersed longitudinally and/or laterally across the cartridge. By way of non-limiting example,FIG. 12illustrates a staple cartridge260for use with the surgical instrument200and having staples270therein with different crown widths W. The staple cartridge260houses three groups of staples270a,270b,270c, each having different widths W1, W2, and W3, respectively, although any number of staple groups is possible. As shown, the groups of staples270a,270b,270ccan be arranged in circumferential rows, with the staples270chaving the largest width W1positioned on an outermost edge of the cartridge260and the staples270ahaving the smallest width W3positioned on an innermost edge of the cartridge260. In other embodiments, staples having a larger crown width can be positioned near an inner most edge of a cartridge and staples having a smaller crown width can be positioned near an outer edge of the cartridge. In still further embodiments, staples along the same row can have different crown widths.

Additionally or alternatively, it may be possible to create a desired tissue compression profile by the creation of different formed (final) staple heights.FIG. 13illustrates an exemplary embodiment of lines of formed staples470′ installed using a surgical stapling instrument as described herein and configured to apply staples470′ having different formed heights as well as to cut tissue to thereby create a cut line494. As shown inFIG. 13, formed heights F1of a first group of staples470a′ in a first row that is the farthest distance away from the cut line494are greater than formed heights F3of a third group of staples470c′ in a third row that is closest to the cut line494. A second group of staples470b′ in a second row that is formed between the first and third rows can have staples470b′ with a formed height F2that is between the heights F1, F3. In other embodiments, formed heights of the staples can decrease from an innermost row to an outermost row. In still further embodiments, formed heights of the staples in a single row can increase or decrease from staple to staple.

Referring again toFIG. 11, differences in formed staple heights can be attained by, for example, altering a staple forming distance A. Forming distances A1, A2can be measured from a seat of staples370a,370b, respectively, within the cartridge360, and an apex of a corresponding forming pocket366of the anvil surface358when the upper jaw354is in the closed position. In one embodiment, for example, a first staple forming distance A1is different from a second staple forming distance A2. Because the forming distance A1is greater than the forming distance A2, the staples370aare not compressed as much as the staples370b, which can alter the formed heights of the staples370a,370b. In particular, greater amounts of compression, corresponding to smaller forming distances, can result in staples with smaller formed (final) heights. It will be understood that similar results may be attained in any desired pattern.

Varied tissue compression gradients can be obtained via patterns in staple orientation within a staple cartridge, for example by the patterns illustrated inFIGS. 14 and 15. In the embodiment depicted inFIG. 14, staple cartridge560can include at least one first staple cavity568aand at least one second staple cavity568bfor housing staples570therein. The first cavity568acan be situated on first lateral side563of the cartridge560and the second cavity568bcan be situated on a second lateral side565of the cartridge560, the first and second lateral sides563,565being separated by a slot567configured to receive a cutting instrument, e.g., the E-beam86, therethrough. The first cavity568acan define a first longitudinal axis569aand the second cavity568bcan define a second longitudinal axis569b. In the illustrated embodiment, the first axis569ais perpendicular, or substantially perpendicular, to the second axis569b. In other embodiments, the first axis569acan be transverse to the second axis569bsuch that axes569a,569bcan create an acute or obtuse angle therebetween. In still other embodiments, the first axis569acan be parallel to, or substantially parallel to, the second axis569b. In some embodiments, at least a portion of the staple cavities568a,568bcan overlap, such that staples570therein can be interlocked when formed. The cartridge560can have a plurality of each of the first and second cavities568a,568b, which can be arranged in any pattern on first and second sides563,565of the cartridge560, for example in rows extending along both sides563,565of the cartridge560along a longitudinal axis Lc of the cartridge560. The staples570housed within the cavities568a,568bcan be implanted into tissue in a pattern determined by the orientation and positioning of the cavities568a,568b. The cartridge560, for example, can be used to implant staples570having different orientations of the staples570on opposite sides of an incision line created by a surgical instrument carrying the cartridge560.

In other embodiments, for example the embodiment of a cartridge660illustrated inFIG. 15, staple cavities668aand668bhaving different orientations can both be disposed on a single lateral side of the cartridge660. As shown inFIG. 15, an axis669aof the first staple cavity668ais perpendicular, or substantially perpendicular, to an axis669bof the second staple cavity668b, both of which are disposed on each of first and second lateral sides663,665of the cartridge660. In other embodiments, the axes669a,669bcan form an acute or obtuse angle therebetween, or can be parallel to one another. A plurality of the first and second cavities668a,668bcan be aligned in adjacent rows along a longitudinal axis Lc′ of the cartridge660on each of the first and second sides663,665of the cartridge660. In this embodiment, staples670housed within the cavities668a,668bcan be implanted into tissue in a symmetrical pattern about an incision line created by a surgical instrument carrying the cartridge660. Greater detail on staple patterns, as well as additional embodiments of such patterns, can be found in U.S. Publication No. 2011/0192882, incorporated herein by reference in its entirety.

Exemplary Compositions for Adjunct Materials

Regardless of the configuration of the surgical instrument, the present disclosure provides for the use of implantable materials, e.g., synthetic and/or biological materials, collectively “adjunct materials,” in conjunction with instrument operations. As shown inFIG. 16, the end effector50can include at least one piece of adjunct material30positioned intermediate the lower and upper jaw members52,54and it can be releasably retained to one of the staple channel56and/or the anvil surface58. In use, the adjunct material30and patient tissue can be captured by staples70when the staples70are fired. Then, the adjunct material30can be separated from the surgical stapler and can remain in the patient when the stapler is removed from the patient. Exemplary devices and methods for attaching one or more adjunct materials to an end effector of a surgical instrument can be found in U.S. Publication No. 2013/0256377 and U.S. Publication No. 2013/0153641, incorporated herein by reference in their entirety.

Adjunct material used in conjunction with the disclosures provided for herein can have any number of configurations and properties. Generally, they can be made from a bioabsorbable material, a biofragmentable material, and/or a material otherwise capable of being broken down, for example, such that the adjunct material can be absorbed, dissolved, fragmented, and/or broken down during the healing process. In at least one embodiment, the adjunct material can be configured to degrade over time to form a gel, e.g., a sealant, to assist in wound healing. In other embodiments, the adjunct material can include a therapeutic drug that can be configured to be released over time to aid the tissue in healing, for example. In further various embodiments, the adjunct materials can include a non-absorbable and/or a material not capable of being broken down, for example.

Some particularly advantageous adjunct materials can include porous polymer scaffolds that can be configured to be broken down, for example by exposure to water such that the water attacks the linkage of a polymer of the material. The degraded material can be configured to gel over a wound site to thereby coat the wounded tissue, e.g., wounded soft tissue, which can aid in compressing, sealing and/or generally creating an environment at the wound site that promotes healing of the tissue. In particular, such degradable polymers can allow for the tissue itself to become the weight-bearing component. In some embodiments, the degraded material can include chemoattractant agents that attract natural healing compounds to the wound site. The polymer scaffolds can be configured to have a desired rate of degradation, for example within minutes to hours after attachment to tissue, to thereby assist in the healing process almost immediately after attachment. For more details on porous polymer scaffolds as described herein, see Q. Chen et al., Elastomeric biomaterials for tissue engineering, Progress in Polymer Science 38 (2013) 584-671, incorporated herein by reference in its entirety.

In some embodiments, the porous polymer scaffolds described herein can be physically crosslinked, which can allow for shaping of the polymer into various complicated three-dimensional shapes, e.g., fibers, sheets, films etc., having any desired porosity, surface-to-volume ratio, and mechanical properties. The scaffold can be shaped into a desired form via a number of methods, for example by extrusion, wet spinning, electrospinning, thermally induced phase separation (TIPS), salt leaching/freeze-drying, etc. Where the scaffold is formed into a film or sheet, the film or sheet can have any desired thickness, for example in a range of about 50 to 750 μm or in a range of about 1 to 3 mm, depending on the desired application.

One embodiment of a porous polymer scaffold includes multiple layers, each of which can perform different wound healing functions. In an exemplary embodiment, the scaffold includes three layers. The first layer can be made from polyester carbonate urethane urea (PECUU), the second layer can be made from poly(ester urethane) urea (PEUU), and the third layer can be made from poly(carbonate urethane) urea (PCUU) lysine triisocyanate (LTI) or hexamethylene diisocyanate (HDI). A person skilled in the art will appreciate that the properties of each layer can be optimized to achieve desired results and performance. In some embodiments, the desired properties of the scaffold can be achieved by blending or copolymerizing the material of the third layer or copolymerized with various polymers or copolymers. By way of non-limiting examples, the material of the third layer can be blended with a polyester copolymer, for example polycaprolactone (PCL), polyglycolic acid PGA, poly(D,L-lactic acid) (PDLLA), PGA, and/or polyethylene glycol (PEG). Where the material of the third layer is blended with both the polyester copolymer and the PEG, a ratio of the polyester to the PEG in the third layer can be about 50:50. In another exemplary embodiment, the PCL can be present in a range of about 60-70% weight/volume, the PGA can be present in a range of about 20-30% weight/volume, the PEG can be present in a range of about 50% weight/volume, and the PDLLA can be present in a range of about 10% weight/volume.

The three-layered film can be configured to degrade almost immediately upon attachment to tissue, for example within about 1 to 2 hours after attachment, although each of the three layers can be configured to degrade differently to have different healing benefits. The order, number, and thickness of each of the layers can vary, and can be tailored to create desired degradation and/or compression ratios. In some embodiments, the first, second, and third layers can be formed on top of a base material or substrate, for example on top of PCL, which can be configured to aid in mechanical compression of the wounded tissue.

Another exemplary embodiment of a porous polymer scaffold can be synthesized from polyhydroxyalkanoate (PHA). In an exemplary embodiment, the PHA can be naturally produced from a variety of microorganisms, e.g., Gram-negative or Gram-positive bacteria, or it can be synthesized, e.g., similar to the production of Biopol®, available from Zeneca of London, United Kingdom. Because PHAs are very quick to dissolve, scaffolds made from PHA can begin to degrade within 20 to 30 minutes after attachment to tissue via contact with heat and/or water. Where the PHA scaffold has a higher molecular weight, the degradation time can be higher, for example in a range of about 30 minutes to about 10 hours. The PHA can be formed into a very thin film, for example a film having a thickness of less than 0.1 mm, e.g., in a range of between 50 to 750 μm. In some embodiments, the PHA can be copolymerized and/or blended with one or more additional materials. By way of non-limiting example, the PHA can be copolymerized with hydroxlvalerate (HV), hydroxylbutyrate (HB), and/or hydroxylhexanoate (HH), which can reduce a level or crystallinity and/or brittleness of the PHA. In other embodiments, the PHA can be blended with one or more thermoplastics, e.g., poly(lactic acid) (PLA), PGA, PCL, starch, etc., to thereby customize a molecular weight and resultant mechanical properties of the scaffold. In certain aspects, one or more of the polymers can be a thermoplastic polymer.

In other embodiments, the scaffold can be synthesized from poly(polyol sebacate) (PPS), e.g., from poly(glycerol-sebacate) (PGS). Such scaffolds can be particularly biocompatible and can provide an additional advantage of reducing a risk of infection in addition to promoting healing. Other exemplary embodiments can be synthesized from xylitol-based elastomers, for example polyxylitol sebacates (PXSs), which can offer structural stability over a clinically required period and/or can enter the metabolic pathway slowly without causing rapid fluctuations of blood glucose levels. Scaffolds made from PXS's can be formed into a thicker film to thereby provide greater compression to the wound site, and can be configured to degrade within a range of about 10 hours to 8 days after attachment. Still other exemplary embodiments can be synthesized from poly(glycerol sebacate-co-acrylate) (PGSA), which can promote tissue in-growth into the scaffold, particularly when formed as a fiber, and/or can serve as an antibacterial agent. PGSA scaffolds can be useful as a replacement for traditional surgical sutures and staples, and/or can serve as a waterproof sealant for hollow organ anastomoses (e.g., ducts, intestine, etc.), 2D mesh grafts (e.g., treatment of hernias, ulcers, burns, etc.), and/or wound dressings (e.g., hemostatic patches, etc.). The PGSA can be combined with glycerol, which can allow the scaffold to last longer in situ, for example up to 20 days.

In yet another embodiment, the scaffold can be made from poly(ε-caprolactone) (PCL), which can be blended with silk fibroin (SF) and which can be formed into a very thin film. The PCL/SF blend can have highly biocompatible properties and/or can improve cell attachment and/or proliferation to the scaffold. For example, when implanted onto tissue, the scaffold can release fibroin into the tissue to thereby promote faster healing, nearly immediate hemostasis, and/or to attract fibroblasts in greater numbers. The PCL component can further assist in the healing process by providing mechanical compression of the wounded tissue. A higher PCL content can provide better mechanical properties, while a higher SF content can provide better degradation properties. In general, the PCL content can be in a range of about 50 to 90% weight/volume and the SF content can be in a range of about 10 to 50% weight/volume. More details on the properties and manufacturing methods for scaffolds made from PCL and SF can be found in Jun Sik Lim et al., Fabrication and Evaluation of Poly(epsilon-caprolactone)/Silk Fibroin Blend Nanofibrous Scaffold, Biopolymers 97: 265-275 (2012), incorporated herein by reference in its entirety.

In still further embodiments, the scaffold can include PCL coated with a gelatin. The scaffold can be arranged in one or more layers, for example with the PCL serving as a substrate. The PCL can function to increase a mechanical strength of the scaffold and/or can support fibroblast adhesion and cell proliferation. More details on the properties and manufacturing methods for scaffolds made from gelatin-coated PCL can be found in Pengcheng Zhao et al., Biodegradable fibrous scaffolds composed of gelatin coated poly(ε-caprolactone) prepared by coaxial electrospinning, J. Biomed Mater Res 83A: 372-382 (2007), incorporated herein by reference in its entirety.

Table 1 below outlines exemplary molecular weight ranges, approximate absorption times, and average dimensions of films made from the aforementioned porous polymer scaffold materials. It will be appreciated by a person skilled in the art that the ranges provided in Table 1 are not intended to be limiting, and that a molecular weight of any of the polymers described herein can be altered to obtain the desired degradation properties.

Other suitable adjunct materials can include absorbable polyurethanes, e.g., polyurethanes derived from aromatic absorbable isocyanates that can be similar to methylene bis(phenyl isocyanate) (MDI) and chain extender diols. The absorbable polyurethanes can be configured to hydrolytically degrade into safe and biocompatible products upon hydrolysis. Non-limiting examples of hydrolysable aromatic isocyanates that can be used to form the absorbable polyurethanes include glycolate-diisocyante, caprolactone-diisocyanate, glycolate-ethylene glycol-glycolate, glycolate-diethylene glycol-glycolate, lactate-diethylene glycol-lactate, trimester of gycolic acid with trimethylpropane, and tetraester of glycolic acid with pentaerythritol.

Another particularly advantageous adjunct material that can be used in conjunction with the disclosures provided herein are the materials that form the multilayered dressings disclosed in U.S. Publication No. 2006/0257458, incorporated herein in its entirety, which are particularly suited to absorb and retain fluids when compressed, e.g., by the application of staples. Other exemplary, non-limiting examples of synthetic materials that can be used in conjunction with the disclosures provided for herein, e.g., as a buttress, include biodegradable synthetic absorbable polymer such as a polydioxanon film sold under the trademark PDS® or with a Polyglycerol sebacate (PGS) film or other biodegradable films formed from PGA (Polyglycolic acid and various forms thereof, marketed under the trademarks Vicryl, Dexon, and/or Neoveil), PCL (Polycaprolactone), PLA or PLLA (Polylactic acid), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25, sold under the trademark Monocryl), PANACRYL (Ethicon, Inc., Somerville, N.J.), Polyglactin 910, Poly glyconate, PGA/TMC (polyglycolide-trimethylene carbonate sold under the trademark Biosyn), polyhydroxybutyrate (PHB), poly(vinylpyrrolidone) (PVP), poly(vinyl alcohol) (PVA), polydioxanone (PDO) and various forms thereof (e.g., marketed under the trademark PDS) or a blend or copolymerization of any of the above. Blends and/or copolymerizations of any of the aforementioned materials can be tailored to have a desired molecular weight and/or degradation rate.

Some non-limiting examples of biologic derived materials that can be used in conjunction with the disclosures provided for herein, e.g., as a sealant material, include platelet poor plasma (PPP), platelet rich plasma (PRP), starch, chitosan, alginate, fibrin, thrombin, polysaccharide, cellulose, collagen, bovine collagen, bovine pericardium, gelatin-resorcin-formalin adhesive, oxidized regenerated cellulose, regenerated cellulose, mussel-based adhesive, poly (amino acid), agarose, polyetheretherketones, amylose, hyaluronan, hyaluronic acid, whey protein, cellulose gum, starch, gelatin, silk, Progel®, available from Davol Inc. of Warwick, R.I., TachoSil®, available from Baxter of Deerfield, Ill., or other material suitable to be mixed with biological material and introduced to a wound or defect site, including combinations of materials, or any material apparent to those skilled in the art in view of the disclosures provided for herein. Biologic materials can be derived from a number of sources, including from the patient in which the biologic material is to be implanted, a person that is not the patient in which the biologic material is to be implanted, or other animals.

Additional disclosures pertaining to synthetic or polymer materials and biologic materials that can be used in conjunction with the disclosures provided herein can be found in U.S. Pat. No. 7,772,352, PCT Publication No. WO 2014/016819, U.S. Patent Application Publication No. 2006/0257458, U.S. Patent Application Publication No. 2012/0080335, U.S. Patent Application Publication No. 2012/0083835, U.S. Patent Application Publication No. 2013/0256372, U.S. Patent Application Publication No. 2013/0256365, U.S. Patent Application Publication No. 2013/0256376, U.S. patent application Ser. No. 13/710,931, entitled “Electrosurgical End Effector with Tissue Tacking Features,” and filed on Dec. 11, 2012, and U.S. patent application Ser. No. 13/763,192, entitled “Multiple Thickness Implantable Layers for Surgical Stapling Devices,” and filed on Feb. 8, 2013, each of which is incorporated by reference herein in its entirety.

Adjuncts Having Strain Relieving Features

A tissue adjunct can have various configurations, but can generally be configured to contact tissue as the tissue is clamped between a cartridge assembly and an anvil of a surgical stapler. One advantage of tissue adjuncts is their propensity to prevent or minimize leaks, such as fluid or gas leaks. Tissue adjuncts can perform this function by one or more of the following mechanisms: plugging holes or tears that occur at the staple puncture sites; restricting movement of tissue around staple puncture sites to prevent an increase in the size of staple holes and/or to prevent tissue tears; and minimizing strain gradients that occur between constrained tissues within the staple line and free tissue adjacent to the staple line.

In certain aspects, the adjunct material can be used to distribute the compressive clamping force over the tissue, absorb and retain beneficial fluids at the treatment site, improve the purchase of the staples, and/or promote hemostasis. In some embodiments, a first piece of adjunct material can be attached to a cartridge assembly and a second piece of adjunct material can be attached to an anvil; however, any suitable number of adjunct materials can be situated within the end effector.

The tissue adjunct can include various features and be formed from various materials for assisting with sealing of tissue at a staple line and/or for preventing the formation of leaks in the tissue. For example, a tissue adjunct can have a central region configured to be deployed onto tissue and attached thereto via staples. The tissue adjunct can further include an outer region, also referred to herein as a wing region or wing portion, which can be positioned outside of a staple line when the adjunct is stapled to tissue. The wing portion can help to more evenly distribute strain and/or minimize strain gradients across a tissue as the tissue deforms or otherwise expands and contracts during normal bodily functions. In some embodiments, a sealant can be used in conjunction with the adjunct to help seal the stapled tissue. The sealant can be introduced into a patient in a first, liquid state and can be configured to transition to a second, hardened or solid state after a predetermined amount of time. When the sealant is in the first, liquid state, the sealant can seep into the adjunct and/or the staple line and then harden therein, thereby facilitating complete sealing of the tissue. The adjunct and the sealant can thus cooperate to provide a better, more complete seal of the staple line than if only the tissue adjunct or the sealant were used.

Exemplary adjuncts having central and wing regions are shown deployed onto tissue inFIGS. 17A and 17B. As shown inFIG. 17A, an adjunct1000can include a central region1002for receiving staples therethrough and a wing portion1004adjacent to the central region1002. The central region1002of the adjunct1000can be sized and shaped to correspond to a size and shape of a cartridge assembly52and/or an anvil (not shown). For example,FIG. 17Aillustrates an adjunct1000having a central region1002that corresponds in size and shape to a tissue-contacting surface of the cartridge assembly52. That is, the central region1002can be substantially equal in size to the tissue-contacting surface. The central region1002of the adjunct1000shown inFIG. 17Acan have a substantially elongate rectangular shape defined by proximal and distal edges1002p,1002dand first and second lateral edges1002a,1002b. The proximal edge1002pof the central region1002can terminate in a proximal mating feature1006for coupling to a distal end14dof a shaft14of a stapler10. At least two of the remaining three edges of the central region1002can include a wing portion1004extending therearound and forming a perimeter of the adjunct1000. For example, as shown inFIG. 17A, the wing portion1004of the adjunct1000can extend around the first and second lateral edges1002a,1002band can extend distally beyond the distal edge1002dof the central region1002. In one embodiment, adjunct1000is sized and position in such a way on cartridge assembly52so that in can be separated by a cutting member in the stapler during use. In fact, a distal region of the wing portion1004is always cut. As shown, the wing portion1004can have a modified structure that is different from a structure of the central region1002. In the illustrated embodiment, the central region1002can be substantially solid, e.g. a film, and the wing portion1004can be a mesh. As shown inFIG. 17B, when the adjunct1000is stapled to tissue T, the central region1002can have one or more rows/lines of staples1008extending therethrough and the wing portion1004can extend laterally away from the staples1008. As shown, the adjunct1000stapled to the tissue T includes half of the adjunct shown inFIG. 17Abecause the cutting member in the stapler severs the tissue while the staples1008are deployed thereon. The meshed wing portion1004can flex as the tissue expands and contracts and more evenly distribute a strain (or minimize a strain gradient) across a greater area of tissue than if the adjunct1000only included the central region1002. For example, the wing portion1004can expand and contract in a direction transverse to the longitudinal axis LC of the central region1002. This can help prevent the formation of pressure points which can create leaks in the stapled tissue after repeated expansion and contraction of the tissue. In certain aspects, the mesh can be formed from threads of the same film material as the central region1002extending in a criss-cross pattern. The longitudinal axis of half of the threads L1can be disposed at an angle θ1of about a 45 degrees relative to the longitudinal axis LC of the central region1002, as shown, and a longitudinal axis L2of the other half of the threads can be disposed at an angle θ2of about a 45 degree angle relative to the longitudinal axis LC of the central region1002, or can be positioned at other angles relative to the central region1002. As will be appreciated by a person skilled in the art, the wing portion1004of the adjunct1000can be formed using various known manufacturing techniques, such as laser cutting or punching shapes such as squares, circles, diamonds, out of the film to produce a mesh wing region and the solid central region1002. Two identical adjuncts1000,1000′ can be stapled to tissue, as shown inFIG. 17B, and in certain aspects, these adjuncts1000,1000′ can be substantially the same in size, shape, and configuration.

Another embodiment of an adjunct1010is shown inFIG. 18and also includes a central region and wing region. In this embodiment, a wing portion1014has a plurality of openings1018formed therein which can allow the wing portion1014to flex with the tissue T during expansion and contraction of the tissue T. The openings1018can have various sizes, shapes, and configurations, and can be circular, oval, rectangular, etc., and can be positioned at various locations across the wing portion1014. In the illustrated embodiment, the openings1018are slits positioned in multiple rows, the rows being substantially parallel to the longitudinal axis LC of a central region1012. A longitudinal axis of the slits1018can be parallel to a longitudinal axis LS of the staples1008. A number of longitudinal rows and a number of openings1018disposed in each row can vary. In the illustrated embodiment, a row adjacent to the central region1012can have a smaller number of openings1018than a row adjacent to an outermost edge1014aof the wing portion1014. For example, the row adjacent to the central region1012can have about three openings1018formed therein while the row adjacent to the outermost edge1014aof the wing portion1014can have about four openings1018formed therein. In this way, a flexibility of the wing portion1014can increase from the central region1012to the lateral edge and can further facilitate distribution of strain across the tissue T.

FIGS. 19A and 19Billustrate another embodiment of a tissue adjunct having wings for distributing strain across the tissue.FIG. 19Aillustrates an adjunct1020having a central region1022and a wing region1024, both regions being formed from a plurality of layers. As in the previous embodiments, the central region1022can have a substantially rectangular shape. A top layer of material can define the central region1022and both regions1022,1024can be formed from a plurality of layers. The central region1022can have a substantially rectangular shape, but can be shaped in other ways. As shown inFIG. 19A, a top layer of material1026tcan define the central region and can be formed from a flexible material, such as PDS®, PGA, Neoveil®, ORC or other polymers and biologically derived material constructs or combinations disclosed herein. Material geometry and structure (material thickness, fiber orientation, polymer chain orientation, hole patterns, etc.) may be used to create desired isotropic or anisotropic deformation characteristics. A bottom layer of material1026bcan also be substantially flexible, and in certain aspects can have a greater flexibility than the top layer1026t. The bottom layer1026bcan have a shape that corresponds to a shape of the top layer1026t, and is shown having a substantially rectangular shape. The bottom layer1026bcan have a larger surface area than the top layer1026tsuch that the bottom layer1026bextends beyond lateral edges of the top layer1026t. As shown, lateral edges of the bottom layer1026bcan be scalloped, having a plurality of semicircular protrusions1028along the wing portion1024. These semicircular protrusions can be spaced at equal distances apart along the edges, or can be spaced in groups of two, three, four, and the groups of protrusions can be disposed at equal distances apart along the edge. When the adjunct1020is stapled to tissue, the top layer1026tof material1026twill be positioned away from and will not directly contact the tissue, while the bottom layer1026bwill directly contact tissue. Additionally, the protrusions can be positioned away from the staple rows and can distribute a strain across the tissue T to prevent formation of leaks. The bottom layer1062bmay be formed from a flexible material, such as PDS®, PGA, Neoveil®, ORC or other polymers and biologically derived material constructs or combinations disclosed herein. Material geometry and structure (material thickness, fiber orientation, polymer chain orientation, hole patterns, etc.) may be used to create desired isotropic or anisotropic deformation characteristics. In an embodiment, at least one of top layer1062tand bottom layer1062bis at least partially comprised of PDS® to aid in attachment of adjacent layers. In an embodiment, both the top layer1062tand bottom layer1062bare created from absorbable materials.

The adjunct material can be constructed in various ways. For example, the adjunct material can be formed from a continuous material. That is, as shown inFIG. 19B, the adjunct1020can include a single layer with the central region1022and the wing portion1024having the plurality of protrusions1024for distributing a strain. In other aspects, the adjunct can include more than two layers of material. For example, one or more intermediate layers of material (not shown) can be positioned between the top layer and the bottom layer and can be more rigid than the top and bottom layers. The layers can be coupled together using known manufacturing techniques, such as lamination, adhesive, etc. The protrusions1028on the wing portion1024of the adjunct can also be formed using known manufacturing techniques, such as laser cutting, stamping, punching, etc.

Another exemplary adjunct is shown inFIG. 20and includes a wing region having a varied geometry. As shown, an adjunct1020′ can have a wing region1024′ extending around a perimeter of the central region1022′ and can have a plurality of surface features1028′ formed therein and spaced evenly along the wing region1024′. The surface features1028′ can be generally shaped as a boomerang and can include an elbow1023′ and first and second arms1025′,1027′ extending therefrom. As shown inFIG. 20, the elbow1023′ can be positioned along edges1022a′,1022b′,1022c′ of the central region1022′ while terminal ends of the arms1025′,1027′ can be positioned at an outer edge of the wing region1024′. In this way, a thickness of the wing region1024′ in a direction transverse to a longitudinal axis of the central region1022′ can vary and a thickness of the wing region1024′ in a direction parallel to the longitudinal axis of the central region1022′ can also vary. These surface features1028′ can be formed by removing a portion of the adjunct material1020′ using known manufacturing techniques, such as laser cutting, stamping, punching, etc.

FIGS. 21A-21Cillustrate adjunct material including wing portions with modified edges. For example, a wing portion1034of an adjunct1030ofFIG. 21Acan have an outer edge in the shape of a sine wave with peaks1034pand valleys1034valong its length so that the wing portion1034is atraumatic and does not increase a likelihood of forming leaks in tissue. A wing portion1034′ ofFIG. 21Bincludes a first material forming a central region1032′ and the wing portion1034′, the wing portion1034′ having curved edges which loop around and extend toward the central region1032′, and back toward the edge forming an oblong opening1035′. In certain aspects, a second material is disposed in the oblong, teardrop shaped openings1035′, such as by being laminated to the first material to form the adjunct1030′. A thickness of this second material can vary from a thickness of the first material. For example, the thickness of the second material can be less than the thickness of the first material1036′, as shown. A wing portion1034″ ofFIG. 21Ccan have a plurality of openings1035″ formed therein, such as triangular shaped openings, that can form protrusions similar to those protrusions1028shown inFIG. 19B, but the protrusions can have corners rather than rounded edges. The adjuncts1030,1030′,1030″ ofFIGS. 21A-21Ccan be formed from different materials, such as any flexible or stretchable polymer material described herein. In use, any one of the adjuncts1030,1030′,1030″ can be stapled to tissue and any of the respective wing portions can extend beyond the staple line. A shown inFIG. 21D, the adjunct1030can be stapled to tissue T and the wing portion1034can be positioned outside of the staples1008which form a staple line and the central portion1032can be positioned inside of the staple line. In certain aspects, as the tissue expands and contracts, the adjuncts can stretch or flex in a direction transverse to the staple rows or can be configured to stretch in multiple directions, such as along an outer surface of the tissue T as shown. A person skilled in the art will appreciate that the edges of the wing portions can be shaped in other ways than the illustrated embodiments.

FIGS. 22A-22Cillustrate another embodiment of adjunct material including a wing portion with modified edges. As shown inFIG. 22A, an adjunct material1040can be woven. A central region1042of the adjunct1040can be formed from a woven material of higher density than a woven material at a wing portion1044of the adjunct1040. In other aspects, a less dense woven material can encase a denser woven material on all sides, as shown inFIG. 22B. In both embodiments, the wing portion1044can have soft, atraumatic edges1046that have a decreased likelihood of puncturing or otherwise damaging the tissue and causing holes to form therein. The adjunct1040can be configured to wick and/or absorb liquid therein. For example, in the embodiment ofFIG. 22C, a top layer1048t′ of material of an adjunct1040′ is shown positioned over a bottom layer of material1048b′, liquid1047′ being wicked through the top layer of material and into a space between the top and bottom layers1048b′,1048t′. These adjunct materials can be formed from various woven materials known in the art, such as ETHISORB® (Ethicon, Inc., Somerville, N.J.). In one embodiment, central region1042may be a film comprised of solid, but deformable absorbable material.

An adjunct material for use with a stapler that deploys variable thickness staples is shown inFIGS. 23A-23D. As shown, a thickness of an adjunct1050can vary from a central axis1056to an outer edge of the adjunct1050in a lateral direction indicated by arrows. That is, the adjunct1050can have a decreasing/tapering thickness from the central axis1056of the adjunct1050to the outer edge thereof in the lateral direction. As in the previous embodiments, the adjunct material1050can include a central region1052and wing portion1054. The adjunct1050can include an elongate slot1058formed along the central axis1056of the adjunct1050and having a size and shape that corresponds to a size and shape of a cutting member (not shown). In the illustrated embodiment, the elongate slot1058has a substantially rectangular shape.FIGS. 23B and 23Cprovide end views of a cartridge assembly52and an anvil54having a varying thickness in a lateral direction such that the stapler10can deploy staples (not shown) of varying heights. As shown, a thickness Taof the anvil54near the cutting member slot can be greater than a thickness Toof the anvil54near its lateral edge. The adjunct1050can be coupled to the cartridge assembly52and/or to the anvil54with at least the central region1052of the adjunct1050directly contacting the tissue-contacting surface60,58of the cartridge assembly52/anvil54. The tissue-contacting surface58of the anvil54can include one or more mating points attaching the adjunct1050to the anvil54, as shown. The wing portion1054of the adjunct1050can be folded around the cartridge assembly52and/or the anvil54and attached thereto, as will be described in greater detail below. In this way, a tissue-contacting surface1053of the first adjunct1050can be substantially planar and can be disposed parallel to a tissue contacting surface1053′ of the second adjunct1050′ disposed on the cartridge assembly52. When the adjuncts1050,1050′ are stapled onto tissue, as shown inFIG. 23D, the wing portion of the adjunct1050can be disposed between the staples1008and extend toward a cut terminal end TEof the tissue T, while a second portion of the adjunct1050can extend away from the cut terminal end TEof the tissue T and distribute strain to the tissue T, similar to the wing portions described above. The adjunct1050′ can have similarly positioned portions1052′,1054′, as shown.

Any of the adjunct materials can include various features for increasing friction between the adjunct material and the tissue to ensure that the adjunct material remains in a desired position. For example, adjuncts1060,1060′ inFIGS. 24A and 24Binclude a plurality of teeth1061,1061′ formed on a tissue-contacting surface thereof and terminating in points1063,1063′ that can penetrate into tissue. As shown, the plurality of teeth1061,1061′ can be spaced at equal distances apart in the lateral direction of the adjunct1060,1060′. The teeth1061,1061′ can be formed in the adjunct1060,1060′ using various known manufacturing techniques, such as via compression molding, cut/stamping, punching, etc. For example, the adjunct1060ofFIG. 24Acan be compression molded while the adjunct1060′ ofFIG. 24Bcan be formed from stamping slits1065′ into material to form the teeth1061′. The gaps between the teeth1061,1061′ can push into tissue T and create a lock that prevents sliding of the adjunct1060,1060′, as inFIG. 24Cwhich illustrates multiple rows of adjuncts1060′. In another embodiment shown inFIG. 25A, the adjunct1060″ can include a plurality of micropillars1063″ formed on a tissue-contacting surface thereof, the micropillars1063″ being shaped as needles configured to penetrate into tissue T. The teeth1061,1061′ and/or micropillars1063″ can directly penetrate into the tissue T as shown inFIGS. 24D and 25Band can thereby prevent the adjunct1060,1060″ from sliding relative to the staples1008as the tissue T expands and contracts. In certain aspects, the micropillars1063″ can have a diameter D1in the range of about 0.01 to 0.50 mm and a height H1in the range of about 0.05 to 0.50 mm.

Another embodiment of an adjunct material is shown inFIGS. 26A-26C. In this embodiment, an adjunct material such as the adjunct1000ofFIGS. 17A and 17Bis used in conjunction with a nose extension member1070that can be coupled to an anvil54and/or a cartridge assembly52of a surgical stapler10. As shown inFIG. 26A, a distal end1004dof the adjunct1000, that is, the distal end1004dof the wing portion1004can terminate at or proximal to a distal-most end52dof the cartridge assembly52. As shown inFIG. 26B, a distal end1004dof the adjunct1000, that is, the distal end1004dof the wing portion1004can terminate at or proximal to a distal-most end54dof the anvil54. The nose extension member1070can be added onto the cartridge assembly52and/or the anvil54to replace or supplement a distal portion of the adjunct material1000. A proximal end1070pof the nose extension member1070can have a cutout1072formed therein and sized so as to not obstruct or cover a slot formed in the anvil54for receiving a cutting member (not shown). The cutout1072can define first and second extension arms1074a,1074bwhich can be releasably coupled to the distal end54dof the anvil54along a curved portion of the anvil54that is distal to the anvil's54tissue contacting surface in various ways, such as using an adhesive. A distal-most end1070dof the nose extension member1070can be substantially rounded. A mechanism for releasing a distal portion1076of the nose extension1070from the proximal end1070pof the nose extension1070can also be provided. In certain aspects, this releasing mechanism can consist of a perforation1078extending transverse to a longitudinal axis LN of the nose extension member1070. In use, an adjunct1000can be positioned on the anvil54and the nose extension member1070can also be coupled to the anvil54. The anvil54and cartridge assembly52can grasp tissue T therebetween, and a portion of the adjunct1000can extend distally beyond the nose extension member1070, as shown inFIG. 26B. That is, the distal end1070dof the nose extension member1070can be positioned distal to the distal end1004dof the adjunct1000. The anvil54and the cartridge assembly52can deploy staples1008through the tissue T and through the adjunct1000, while the wing region1004of the adjunct1000does not include staples1008extending therethrough. The wing region1004of the adjunct1000can directly contact the tissue T and the nose extension member1070can be positioned above the wing region1004. In certain aspects, the nose extension member1070can be a semi-flexible material and can be used in conjunction with the adjunct1000to help relieve a strain on tissue T and/or provide strength to the adjunct1000. In use, the distal end of the nose extension member1070can be removed from the anvil54and/or the cartridge prior to, during, and/or after the tissue T is stapled.

While features of the adjunct described above were illustrated as separate embodiments, an adjunct can have any combination of features described above.

Mechanisms for Attaching and Releasing Adjuncts from an End Effector

Various mechanisms can be used to attach and then release an adjunct having wings from an end effector, e.g. a cartridge assembly52or an anvil54. While the embodiments described below include features formed on an anvil54, any of these features can be formed on a cartridge assembly52for mating an adjunct to the cartridge assembly52.FIGS. 27A-27Billustrate adjunct material1000′,1000″ having mating features keyed to corresponding mating features formed on an anvil54. More specifically,FIG. 27Ashows an adjunct1000′ having a plurality of cylindrical protrusions1003′ formed on a surface1007′ that is oriented away from a tissue contacting surface1005′ of the adjunct1000′. WhileFIG. 27Aillustrates three cylindrical protrusions1003′ spaced apart along an axis parallel to a longitudinal axis LA of the anvil54, any number of protrusions1003′ can be formed at various locations along the adjunct1000′. A lateral surface54L of the anvil54can have a plurality of depressions53configured to receive the plurality of protrusions1003′ from the adjunct1000′ therein. In one embodiment, a height (not shown) of the cylindrical protrusions1003′ can vary, and can be in the range of about 0.25 to 1.00 mm, the height measured perpendicular to the surface1007′ of the adjunct1000′. The protrusions1003′ formed on the adjunct1000′ can have other sizes and shapes. As shown inFIG. 27B, in another embodiment, an adjunct1000″ can have a single elongate rectangular protrusion1003″ extending parallel to the longitudinal axis LA of the anvil54. A lateral surface of the anvil54can also include a corresponding elongate rectangular depression53′ for receiving the rectangular protrusion1003″ therein when the adjunct1000″ is folded around the anvil54. A height (not shown) of the rectangular protrusion1003″ can also vary, but can be in substantially the same range as the height of the cylindrical protrusions1003′ described above. While only a first lateral surface54L of the anvil54is shown inFIGS. 27A and 27B, a person skilled in the art will appreciate that identical protrusion(s) can be formed on a second lateral surface (not shown) of the anvil54. Similarly, identical depression(s) can be formed on a second lateral surface (not shown) of the adjuncts1000′,1000″.

An adjunct can be coupled to an anvil/cartridge assembly in other ways. As shown inFIGS. 28A and 28B, a strand of suture can couple the adjunct to the anvil54. The suture can extend from the first lateral surface54L of the anvil54, across the tissue-contacting surface of the adjunct, and to the second lateral surface55L of the anvil54. First and second depressions53′″,55′″ can be formed in the first and second lateral surfaces of the anvil54, and a first terminal end of the suture can be received in the first depression53′″ and a second terminal end can be received in the second depression55′″. A length of the suture and/or a size of the depressions53′″,55′″ can be selected so that the suture is taut when the terminal ends of the suture1003′″ are positioned within the depressions53′″,55′″. As a cutting member59advances through the anvil54during and/or after the staples1008are deployed into the tissue T, as shown inFIG. 28B, the cutting member59can sever the suture, causing the terminal ends of the suture1003′″ to slide out of the depressions53′″,55′″ and thereby releasing the adjunct from the anvil.FIGS. 29A and 29Billustrate the strand of suture1003′″ extending around an anvil54and coupling a multi-layer adjunct1020to the anvil54. As in the previous embodiment, advancement of the cutting member (not shown) relative to the anvil54can sever the suture1003′″ and release the suture1003′″ from the depressions53′″,55′″ in the anvil54to release the adjunct1020. As will be appreciated by a person skilled in the art, any number of strands of suture can be used to couple the adjunct to one of the cartridge assembly52and the anvil54and the depressions formed therein can vary so long as they are configured to receive a portion of the suture therein.

FIGS. 30A-30Billustrate other mechanisms for attaching an adjunct to an anvil/cartridge assembly. In this embodiment, the anvil54of a surgical stapler10includes a cutting member59that can advance within a slot61, referred to as a longitudinal track, and can move between proximal and distal ends61p,61dof the track61. A driver including first and second elongate members (not shown) can be disposed in the longitudinal track61, as inFIG. 30B. Three cylindrical protrusions (not shown) extend from the elongate members and into depressions53″″,55″″ formed in both lateral surfaces of the anvil54, but there can be any number of protrusions spaced along the driver and having various other shapes. As shown inFIG. 30C, a first driver1081acan be generally elongate and can have a plurality of protrusions1083, such as three protrusions1083, oriented transverse to a longitudinal axis of the driver, the protrusions1083being cylindrical shaped. A wing portion1084of an adjunct material1080can be disposed around a lateral surface of the anvil54and can include a plurality of protrusions1083′ oriented transverse to the longitudinal axis LA of the anvil54when the adjunct material1080is coupled thereto. As shown inFIG. 30D, the adjunct material1080can have a first set of protrusions1083′ for mating with the first lateral surface of the anvil54and a second set of protrusions1083″ for mating with the second lateral surface of the anvil54. Prior to use, the first driver1081acan be positioned on a first lateral wall of the track61and the second driver1081bcan be positioned on a second lateral wall of the track61. A proximal end of each driver1081a,1081bcan have an angled portion1085p,1087psuch that when the drivers1081a,1081bare disposed in the track61, a width W1between the drivers1081a,1081bat a proximal end of the track61is greater than a width W2between the drivers1081a,1081bat and/or distal to the protrusions1083′, the width being measured transverse to the longitudinal axis LA of the anvil54as shown inFIG. 30E. Additionally, the width W2between the drivers1081a,1081bdistal to the proximal end61pof the track61can be less than a width WC of the cutting member59. In this way, the cutting member59can be advanced toward the distal end54dof the anvil54and can increase a width between the drivers1081a,1081band the protrusions1083can push the corresponding protrusions1083′ on the adjunct1080off of and away from the anvil as inFIG. 30F, thereby releasing the adjunct from the anvil54. In certain aspects, the adjunct1080can be biased to a flattened, substantially planar configuration such that when the cutting member59advances within the track61and exerts a force on the drivers1081a,1081b, the adjunct1080is more able to release from the anvil54.

A loading mechanism for loading an adjunct onto an anvil/cartridge assembly is shown inFIGS. 31A-3B. A loading mechanism1090can have various sizes, shapes, and configurations, and can include a first curved arm1092aand a second curved arm1092bhaving a radius of curvature that corresponds to a radius of curvature of the first and second lateral surfaces54L,55L of the anvil54and the arms1092a,1092bcan terminate in angled features1093a,1093bthat can be grasped by a user. The loading mechanism1090can have a planar base1094from which each of the first and second curved arms1092a,1092bextend. The base1094of the loading mechanism1090can further include a track extension1094eextending perpendicular to the base1094and disposed along a central longitudinal axis of the loading mechanism1090for insertion into the cutting member slot54sin the anvil54, as shown inFIG. 31B. A first inner surface1094aof the loading mechanism1090can be defined by the first curved arm1092aand a first portion of the base1094from the first arm1092ato the track extension, as shown inFIG. 31A. Likewise, a second inner surface1094bof the loading mechanism1090can be defined by the second curved arm1092band a second portion of the base1094from the second arm1092bto the track extension1094e. In this way, the loading mechanism1090can be generally E-shaped for receiving the anvil54. An adjunct1000having a central region1002and a wing region1004can be positioned and sandwiched between inner surfaces of the loading mechanism1090and the tissue-contacting surface of the anvil54, as inFIG. 31B, the loading mechanism1090clamping onto the anvil54as shown. The track extension1094ecan facilitate achieving a tight fit between the loading mechanism1090, the adjunct1000, and the anvil54with substantially no gaps between. After the adjunct1000is coupled to the anvil54, such as using any attachment mechanisms described herein, such as attachment mechanisms1095, the loading mechanism1090can be removed from the anvil54. This can be accomplished, for example, by pressing the angled features1093a,1093bof the curved arms away1092a,1092bfrom one another, leaving the anvil54loaded with the adjunct1000as inFIG. 31C.

Another exemplary loading mechanism is shown inFIGS. 32A-32C. A loading mechanism1090′ can be packaged as a kit along with an end effector of a stapler. Alternatively, loading mechanism1090′ may be packaged separately. As inFIG. 32A, the anvil54and cartridge assembly52of the end effector50can include an adjunct material1000preloaded thereon or in another non-illustrated embodiment, the adjunct material1000can be fixed to the anvil54and the cartridge assembly52after being removed from packaging1100. This loading mechanism1090′ can be configured to wrap the wing portion1004of the adjunct1000around the lateral surfaces54L,53L of the anvil/cartridge assembly54,52such that the wing portion is passively coupled to the anvil/cartridge assembly54,52. As shown inFIG. 32B, the loading mechanism1090′ can be configured to contact the central region (not shown) of the adjunct1000against the tissue-contacting surface of the anvil/cartridge assembly54,52and, if needed, can be configured to shape the wing portion (not shown) around the anvil54. The loading mechanism1090′ can be formed of a single molded material having an upper retaining portion1104and a lower retaining portion1102, the retaining portions having a channel (not shown) sized and shaped for receiving the anvil/cartridge assembly54,52therein. A shape of the channel can be substantially similar to the shape of the loading mechanism1090previously described and can include any of the same features, such as the track extension. The upper and lower retaining portions1104,1102can be disposed at an angle θL relative to one another, the angle being in the range of about 10 to 40 degrees. A support member1106can extend between a lower surface of the upper retaining portion1104and an upper surface of the lower retaining portion1102such that the angle θL between the retaining portions1102,1104is fixed. The support member1106can be a substantially solid member, as shown, so as to provide rigidity to the loading mechanism1090′. A first end of the support member1106can terminate in a grasping feature1108, and the grasping feature1108can have first and second planar surfaces1108a,1108bconfigured to be grasped by a user, such as between a thumb and finger of a user. The grasping feature1108can further include one or more surface features1110for increasing friction between a user's fingers. A longitudinal axis of the grasping feature1108can be oriented perpendicular to a longitudinal axis of the stapler10or can be parallel to the longitudinal axis of the stapler10. In use, a user can grasp the grasping feature1108and position distal ends1102d,1104dof the retaining portions adjacent to proximal ends ends52p,54pof the cartridge assembly52and the anvil54. A user can advance the distal end of the loading mechanism1090′ toward the proximal end of the end effector50, as shown inFIG. 32B, and the retaining portions1102,1104can slide along the anvil/cartridge assembly54,52and force the adjunct material1000around the lateral surfaces thereof, as shown inFIG. 32C. This can temporarily secure the wing region1004along the lateral surfaces of the cartridge assembly52and the anvil54. With the wing region1004so positioned, a user can retract the loading mechanism1090′ in the opposite direction, distally away from the end effector50, leaving the end effector50prepared for insertion into a patient. While reference is made to a single adjunct material1000loaded onto the anvil54, adjunct material1000′ can similar be loaded onto the cartridge assembly52. The adjunct material1000, such as the material shown inFIGS. 32A-32C, can be a shape memory material such that the adjunct1000is biased to a substantially straightened configuration. That is, when the end effector50is positioned inside of the patient, the wing regions can automatically move back to the substantially straightened configuration prior to being deployed off of the end effector50and onto tissue.

Delivering Adjuncts into a Patient

End effectors having one or more adjuncts coupled thereto can be delivered into various areas of a patient, such as a chest cavity, stomach, etc. As will be appreciated by a person skilled in the art, an adjunct can be delivered through an access port, such as a trocar extending into the patient. Any of the adjuncts herein can include features that assist with delivery of the adjunct into a patient's body. For example,FIG. 33Aillustrate an adjunct1000having a solid central region1002and mesh wing region1004coupled to an anvil54of a surgical stapler10. While a single adjunct1000is shown coupled to the anvil54, another adjunct1000′ can be coupled to the cartridge assembly52prior to inserting the end effector50into a patient's body. A distal portion of the adjunct1000, such as a distal portion1004dof the wing region1004, can be configured to guide proximal portions1004pof the wing region1004around the lateral surfaces (not shown) of the anvil54so as to minimize width of the adjunct material, as shown inFIG. 33B. This can facilitate insertion of the end effector50and the adjunct1000into an access port, such as a port1202formed in a trocar1200, because a width of the anvil/cartridge assembly54,52including the adjunct1000thereon will be about the same as a width of the anvil/cartridge assembly54,52without an adjunct. In certain aspects, this distal portion1004dof the wing region1004can be formed from a more rigid material than remaining portions of the wing region1004to help guide the adjunct material1000into the port1202.

Stapling Adjuncts onto Tissue

An adjunct material can include features facilitating multiple firings of staples along tissue.FIG. 34Aillustrates an embodiment1300of an end effector50having first and second adjunct materials1400,1400′, the first adjunct material1400being coupled to the anvil54and the second adjunct material1400′ being coupled to the cartridge assembly52. As shown, each of the adjunct materials1400,1400′ can include multiple layers, and the layers can have various widths in the direction transverse to a longitudinal axis (not shown) of the anvil/cartridge assembly54,52. A first tissue-contacting layer1402,1402′ of each adjunct1400,1400′ can be positioned adjacent to tissue (not shown) when tissue is grasped between the anvil54and the cartridge assembly52. In certain aspects, the first tissue-contacting layer1402,1402′ can be formed from a material configured to seal around a staple line, such as an elastomeric material. The first tissue-contacting layer1402,1402′ can have a width W5in a direction transverse to the longitudinal axis LA of the anvil54that is substantially equal to a width WA of the anvil54, or the width W5of the first layer1402can be less than the width WA of the anvil54. As shown inFIG. 34A, the first tissue-contacting layer1402can include a first portion1402apositioned on a first side of the cutting member slot54sand a second portion1402bpositioned on a second side of the cutting member slot54srather than being formed from a continuous piece of material. In other aspects, the first layer1402can be a single continuous piece of material. A second layer1406,1406′ can be positioned closer to the tissue-contacting surface of the anvil54and can be formed from a substantially rigid material. As shown, a width W6of the second layer1406can be greater than the width WA of the anvil54. This second layer1406,1406′ can help prevent stretching of the tissue T near the staples1008. A third layer1408,1408′ can be positioned closest to the tissue-contacting surface of the anvil54such that the second layer1406,1406′ is sandwiched between the first and third layers1402,1402′ and1408,1408′. The third layer1408,1408′ can have a width W7that is greater than the width WA of the anvil54, but less than the width W6of the second layer1406, as shown. This third layer1408,1408′ can be semi-rigid to help relieve strain on tissue T as the tissue T expands and contracts. A longitudinal length of the layers can also vary, the length being measured in the direction transverse to the widths. Preferably, the third layer1408,1408′ has a longest length measured along the longitudinal axis of the anvil54compared to a longitudinal length of each of the first and second layers1402,1402′,1406,1406′. As shown inFIG. 34B, multiple adjuncts1400,1400′,1400″ can be sequentially deployed onto tissue in a row and the longitudinal lengths of the layers can result in regions1410a,1410bwhere the first layer1402of one adjunct1400overlaps with a first layer1402′ of another adjunct1400′. In this way, the staples1008can still penetrate through these overlapping regions than if multiple, e.g. three or more layers1402,1406,1408were positioned there.FIG. 33Cillustrates two adjuncts1400,1400′ stapled onto the tissue T at about a 90 degree angle relative thereto, the first adjunct1400having a first terminal end and the second adjunct1400′ having a second terminal end. The first and second terminal ends form the overlapping region1410a, as shown. These adjuncts1400,1400′ can be used to allow a user to deploy adjuncts to accommodate various geometries of tissue. These multilayer adjuncts1400,1400′ can vary in any number of ways. While the layers1402,1406,1408can have various thicknesses, in the illustrated embodiment the second layer1406has a smaller thickness than a thickness of each of the first and third layers1402,1408. For example, the first layer1402can be in the range of about 3 to 15 mm, the second layer1406can be in the range of about 5 to 20 mm, and the third layer1408can be in the range of about 3 to 20 mm. In certain aspects, these layers1402,1404,1406and1402′,1404′,1406′ can be laminated together prior to being coupled to the anvil/cartridge assembly54,52. In certain aspects, layers1406and1406′ may be at least partially comprised of an absorbable material such as PDS®.

Reinforcing Tissue with Sealant and Adjuncts

Any of the adjuncts herein can be used in conjunction with a sealant to help maintain a seal around staples as the tissue expands and contracts following a surgery. A sealant can have various formulations and differing viscosity and curing behavior. Generally, a sealant can be made from a biocompatible and bioabsorbable material that can be configured to transition from a first, liquid state to a second, hardened state via a curing process, such as a polymerization reaction. The first state can be a softened state, e.g., a fluid, a gel, a foam, etc. and the second state can be a hardened state, e.g., a solid, a rigid member, etc. When the sealant is in the first, softened state, the sealant can flow through the delivery tube and into the sealing cuff, as described in greater detail below. The sealant can transition from the first, softened state to the second, hardened state after a predetermined amount of time. In certain aspects, the sealant can be formed from biologic material. In some embodiments, the sealant can assist in wound healing by releasing various chemical compounds, during and/or after curing of the sealant in a patient's body. By way of non-limiting example, the sealant can be configured to release a therapeutic drug, such as promoters of wound healing (e.g., transforming growth factor-beta, etc.), antibacterial agents (e.g., triclosean, ionized silver, etc.), and other known agents over time to aid the tissue in healing near the location of the sealant in a body. In one embodiment, a fibrin sealant can include two reactive components combined immediately prior to delivery into a patient, such as Thrombin and a biologically active component (BAC2), Fibrinogen and Factor XIII In certain aspects, the components can be provided in a 5:1 volumetric ratio of BAC2 to Thrombin. In an alternative embodiment, the material may be the fibrin sealant sold under the trade name Evicel®. In another embodiment, the sealant can be blood, such as autologous blood.

FIG. 35Aillustrates the adjunct ofFIG. 17Bhaving sealant1500delivered thereon. As shown, the sealant1500can be delivered so that it substantially covers the central1002and wing regions1004of the adjunct1000or in another embodiment (not shown), the sealant1500can be selectively delivered onto only the central region1002and not onto the wing region1004.

The sealant1500can be delivered to an adjunct in other ways, and need not be delivered to an outer surface of the adjunct1000. For example,FIG. 35Billustrates multilayer adjuncts1700,1700′ stapled onto tissue T. The layers1702,1704can be formed from various materials, but in the illustrated embodiment include a first layer1702of fibrous scaffold positioned adjacent to the tissue T and a second layer1704consisting of an elastic film. A delivery tool1706having an injection needle1708can have a sealant1500disposed therein and can penetrate into the first layer1702of fibrous scaffold. The sealant1500can be delivered to this first layer1702, as inFIG. 35Cand the injection needle1708can be removed from the patient's body. The sealant1500can bind directly onto the tissue T and/or may be held in firm apposition to the tissue by layer1704, and as in other embodiments, can have a wing region1710,1710′ that distributes a strain to tissue beyond the staples1008at the staple line. When the sealant is Evicel®, the material forms a fibrin clot from fibrinogen. Without a loss in generality, other sealants form a hardened sealing structure by different mechanisms that are useful for sealing leak pathways. The combination of sealant1500and adjunct material1700can prevent formation of leaks as the tissue T expands and contracts. The adjuncts1700′ and layers1702′,1704′ can be substantially similar to the adjunct1700and1702,1704layers previously described.

A sealant can be used to reinforce tissue in other ways. For example,FIGS. 36A-36Cillustrate sealant1500being delivered to a chest cavity1800of a patient. As shown inFIG. 35A, a system1900for delivering a sealant1500can include a container or canister1902for receiving components A, B, C of a sealant1500therein. In certain aspects, the components A, B, C can include acid solubilized collagen A, fibrinogen B, and thrombin C. A trocar1200can extend through an incision1904formed in a patient1906and into the chest cavity1800. An applicator tool1908can have a shaft1910extending through the trocar1200, a distal end1910dof the shaft1910terminating in the chest cavity. A handle assembly1912can be formed on a proximal end1910pof the shaft1910and can be configured to be grasped be a user. The handle assembly1912can be a pistol-grip type handle assembly and can include one or more actuators, such as a lever1914that can be pivoted to actuate the device1908. The canister1902and the applicator tool1908can be coupled together in various ways, such as via a tube1916. This tube1916can be substantially flexible to facilitate movement of the applicator tool1908during a procedure. The canister1902can have a second tube1918coupled thereto and connected to a gas source S so that gas1920can be delivered to the canister1902. The gas1920can include, by way of non-limiting example, CO2, O2, etc. In certain aspects, the gas source S can be a continuous gas source such as a continuous CO2gas source available in hospital operating rooms. One or more valves (not shown) can be disposed in the tube1916, in the handle assembly1912, in the shaft1910, or in any other portion of the system1900and can be selectively opened and closed by activating the actuator, such as by pivoting the actuator1914on the handle assembly1912. For example, one valve can control influx of the gas1920into the canister1902and another valve can control delivery of the sealant1500into the applicator tool1908. After tissue T is stapled, such as by deploying one or more cartridges of staples onto lung tissue, the distal end1910dof the shaft1910of the applicator1908can be positioned near the staples1008as inFIG. 36B. Preferably, the distal end1910dof the applicator tool1908is positioned about 5 to 30 mm away from a staple line depending on the size of the region to cover. A user can grasp the handle assembly1912of the applicator tool1908and activate the actuator1914, such as by moving the pivotable lever1914proximally. This can open a valve disposed in the system1900and begin delivering the gas1920to the canister1902to nebulize the sealant1500so that it forms encapsulated liquid droplets that can be sprayed directly onto the tissue T, as shown. In this way, the sealant1500can be delivered onto the tissue along the staple line, as shown inFIG. 36C. The sealant1500can harden thereon, forming hardened regions1500hfacilitating formation and maintenance of a seal along the staples1008. The sealant1500can also be delivered onto an adjunct rather than directly onto the tissue T, such as any of the adjuncts described herein. As will be appreciated by a person skilled in the art, sealant can be delivered to any portion of the tissue, such as only the tissue at the staple line and/or beyond the staple line.

A sealant can be delivered in various ways. For example, a system1900′ for delivering a sealant1500is provided inFIG. 37Aand includes many of the features ofFIG. 36A, including a gas source, canister, etc. However, in this embodiment the system delivers a nebulized sealant1500directly through the trocar1200and does not include an applicator tool. In this embodiment, the system also need not include valves and the delivery of the gas1920to the canister1902can simply be controlled using a valve at the gas source. The delivery of gas into the canister1902can also nebulize the sealant1500, but rather than form encapsulated liquid droplets, the gas1920can be delivered at a higher pressure and rate to create a nebulized fog of sealant1600. As shown inFIG. 37B, this sealant fog1500can spread throughout the chest cavity of the patient and can harden on all surfaces of the tissue, such as forming hardened regions1500halong all surfaces of the patient's lungs.

In an embodiment in which the sealant is blood, such as autologous blood, the blood can be harvested from the patient and applied to the adjunct material. By way of non-limiting example, the adjunct material can be ORC, a known hemostatic agent, and the application of the blood to the ORC adjunct will cause the formation of a clot, resulting in an effective sealing structure. A person skilled in the art will appreciate that blood, such as autologous blood can be applied to a variety of adjunct materials to provide an enhanced sealing structure. Further, a person skilled in the art will appreciate that the volume of blood applied to the adjunct will vary depending upon a number of factors, including the type and location of tissue as well, the age and condition of the patient, and the identity of the adjunct. Generally, however, when the adjunct is an ORC material, the blood can be applied in an amount in the range of about 5-10 cc per line of staple used to affix the adjunct to the tissue.

In some embodiments, devices described herein can be processed before surgery. First, a new or used instrument, which can include an adjunct material, is obtained and if necessary cleaned. The instrument can then be sterilized. In some embodiments, the instrument can be dried, e.g., in an oven, together with a desiccant item, which can have a greater affinity for moisture than the adjunct material. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag or a foil bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. In another sterilization technique, the instrument is placed in a first container, such as a plastic or TYVEK bag, having a vapor permeable backing. The first container can then be packaged in a second container, e.g., a foil bag, which can be left open. The first and second containers, together with the instrument, can undergo ethylene oxide sterilization. The second container can then be sealed to prevent moisture exposure. Prior to sealing, a desiccant item may be included in at least one of the first and second containers to further prevent changes to one or more device components. In both techniques, the sterilized materials can then be stored in the sterile container(s) to keep the materials sterile until the container(s) is/are opened in the medical facility.