Abstract:
Devices for and methods that can be used in endoscopic surgery, and more particularly, devices and methods that can be used for endoscopically applying surgical sealants and other fluids to internal organs and tissues.

Description:
TECHNICAL FIELD 
       [0001]    This document relates to devices that can be used in endoscopic or open surgery, and particularly to devices that can be used for applying surgical sealants or other fluids to organs and tissues. 
       BACKGROUND 
       [0002]    Surgical sealants (e.g., the SYLYS® sealant available commercially from Cohera Medical, Inc.; Pittsburgh, Pa.) can be used to prevent leakage of fluids or gas post-surgery. There currently is no applicator available to efficiently and safely apply surgical sealants during endoscopic procedures or during open procedures in the body. 
       SUMMARY 
       [0003]    This document is based at least in part on the development of a device designed for endoscopic (e.g., laparoscopic) application of surgical sealants. The device also can be an effective tool for application of various types of fluids that require endoscopic or open delivery in the body. This device can allow a user to maneuver into a body cavity during endoscopic or open surgery, articulate a delivery tube to a desired application angle, and readily apply an appropriate volume of sealant (or any suitable fluid) to the surface of a desired area. For example, the device can be used to reach into the lower pelvis of a patient and apply a sealant during bowel anastomosis procedures, including open bowel anastomosis procedures and endoscopic procedures. 
         [0004]    In one aspect, this document features an endoscopic device having: an elongate outer tube having a first end, a second end, and a lumen extending axially between the first and second ends of the outer tube, wherein the outer tube comprises a rigid material; an elongate inner tube having a first end, a second end, and one or more lumens and a wire core that extend axially between the first and second ends of the inner tube, wherein the inner tube comprises a flexible material, and wherein the inner tube is positioned within the outer tube; a hub configured to receive and retain the first end of the outer tube and the first end of the inner tube; and a connector fitting configured to engage the hub and a vessel. 
         [0005]    The outer tube can contain stainless steel. In some embodiments, the outer tube can have a length between about 33 cm and about 43 cm, and an external diameter between about 4 mm and about 6 mm. 
         [0006]    The inner tube can have four lumens extending axially between the first and second ends of the inner tube, and/or a polyether block amide formulation. In some embodiments, the inner tube can have a length between about 35 cm and about 45 cm, and an external diameter between about 2 mm and about 4 mm. The wire core can contain stainless steel. In some embodiments, the wire core can have a diameter between about 0.5 mm and about 2 mm. 
         [0007]    The inner tube can be positioned within the lumen of the outer tube such that the first end of the inner tube extends beyond the first end of the outer tube, and the second end of the inner tube extends beyond the second end of the outer tube. 
         [0008]    The hub can have a first end, a second end, a lumen extending axially between the first and second ends of the hub, and an interior surface that defines a protrusion, wherein the protrusion defines the boundaries of a first cavity and a second cavity. The first cavity can be configured to receive and engage a connector fitting, and the second cavity can be configured to receive and retain the first end of the outer tube. The first end of the outer tube can be secured within the second cavity of the hub by a laser weld. The interior surface of the first cavity can define threading configured to receive threading on the connector fitting, such that the connector fitting can be engaged within the first cavity. The connector fitting can be secured within the first cavity by an adhesive. In some embodiments, the connector fitting can be a female connector fitting. 
         [0009]    The device can further have a collar positioned within the second cavity of the hub, wherein the collar is configured to engage the first end of the inner tube. The first end of the inner tube can be attached to the collar by an adhesive. 
         [0010]    In another aspect, this document features a method for applying a surgical fluid to a tissue in a patient. The method can include (a) providing an endoscopic device having (i) an elongate outer tube having a proximal end, a distal end, and a lumen extending axially between the proximal and distal ends of the outer tube, wherein the outer tube comprises a rigid material; (ii) an elongate inner tube having a proximal end, a distal end, and one or more lumens and a wire core that extend axially between the proximal and distal ends of the inner tube, wherein the inner tube comprises a flexible material, and wherein the inner tube is positioned within the outer tube such that the distal end of the inner tube extends from the distal end of the outer tube; (iii) a hub configured to receive and retain the proximal end of the outer tube and the proximal end of the inner tube; and (iv) a connector fitting engaged with the hub and a vessel containing the surgical fluid; (b) inserting a portion of the endoscopic device into the patient such that the distal tip of the inner tube is positioned adjacent to the tissue to which the surgical fluid is to be applied; (c) manipulating the distal end of the inner tube, to direct the distal end toward the portion of the tissue to which the surgical fluid is to be applied; and (d) actuating the vessel such that the surgical fluid passes through the one or more lumens of the inner tube and contacts the tissue. 
         [0011]    The outer tube can contain stainless steel. The inner tube can have four lumens extending axially between the proximal and distal ends of the inner tube. The inner tube can have a polyether block amide formulation. The wire core can contain stainless steel. The vessel can be a syringe. The method can include inserting a portion of the endoscopic device into the patient through an opening in the body (e.g., through a trocar). The method can include manipulating the distal end of the inner tube with a grasping device inserted into the patient. 
         [0012]    The surgical fluid can be a sealant. The patient can be undergoing closure of an anastomotic junction in the gastrointestinal tract, a bowel anastomosis procedure, or an arthroscopic procedure. 
         [0013]    Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although methods and materials similar or equivalent to those described herein can be used to practice the invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting. 
         [0014]    The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0015]      FIG. 1A  is a side view of an embodiment of an endoscopic applicator device as provided herein. 
           [0016]      FIG. 1B  is an exploded view of the embodiment shown in  FIG. 1A . 
           [0017]      FIG. 2A  is an exploded view of an outer tube and a hub from an embodiment of an endoscopic device as provided herein. 
           [0018]      FIG. 2B  is a side view of the outer tube of  FIG. 2A  assembled with the hub. 
           [0019]      FIG. 3A  is a cross-sectional view of an embodiment of a hub as provided herein. 
           [0020]      FIG. 3B  is a cross-sectional view of the hub of  FIG. 3A , engaged with an end of an outer tube. 
           [0021]      FIG. 4A  is a cross-sectional view of an embodiment of an inner tube that can be included in an endoscopic device as provided herein, where the inner tube has one lumen. 
           [0022]      FIG. 4B  is a cross-sectional view of an embodiment of an inner tube that can be included in an endoscopic device as provided herein, where the inner tube has two lumens. 
           [0023]      FIG. 4C  is a cross-sectional view of an embodiment of an inner tube that can be included in an endoscopic device as provided herein, where the inner tube has four lumens. 
           [0024]      FIG. 5A  is a cross-sectional view of an embodiment of the distal end of a device as provided herein, showing an inner tube protruding from the distal end of an outer tube. 
           [0025]      FIG. 5B  is a side view of a distal end as shown in  FIG. 5A , where the distal end is in a bent configuration. 
           [0026]      FIG. 6A  is a cross-sectional view of an embodiment of the proximal end of a device as provided herein, showing a hub engaged with an outer tube, a collar, and an inner tube. 
           [0027]      FIG. 6B  is a cross-sectional view of a proximal end as shown in  FIG. 6A , with the hub being further engaged with a connector fitting. 
       
    
    
       [0028]    Like reference symbols in the various drawings indicate like elements. 
       DETAILED DESCRIPTION 
       [0029]    This document provides devices and methods for targeted delivery of surgical sealants (or other fluids) within the body during endoscopic or open surgeries. The devices provided herein can allow a user to maneuver into a body cavity during a surgical procedure, articulate a delivery tube to a desired application angle, and apply an appropriate volume of fluid to a desired area. For example, the devices disclosed herein can be used to reach into the lower pelvis of a patient and apply a sealant during a bowel anastomosis procedure. 
         [0030]    In general, the devices provided herein include an elongate outer tube and an elongate inner tube, where the inner tube has a co-extruded wire core and two or more lumens extending between its first and second ends. The outer tube can be rigid, while the inner tube can be flexible. The inner tube fits within the outer tube, and a first end (e.g., the proximal end) of each tube is held within a single hub. The second end (e.g., the distal end) of the inner tube extends beyond the second end of the outer tube, and due to the presence of the co-extruded wire core, can be bent by a user to a desired angle. The hub also has a means for connecting to a vessel (e.g., a syringe) containing a fluid to be delivered through the device. 
         [0031]    An exemplary embodiment of such a device is depicted in  FIGS. 1A and 1B . The device  100  can have an outer tube  110 , an inner tube  120 , and a hub  130 . In addition, the device  100  can include a connector fitting  140  that can be connected to the hub  130 , and a collar  150  that can fit within the hub  130  for attachment of the inner tube  120 , as described below. In some embodiments, the connector fitting  140  can be a luer fitting. As depicted in  FIG. 1B , the device  100  also can include a first adhesive  160  and a second adhesive  170 , which can attach various elements of the device  100  to one another. 
         [0032]    With further reference to  FIGS. 1A and 1B , and also to  FIGS. 2A and 2B , the device  100  can have an outer shell that includes the outer tube  110  and the hub  130 . The outer tube  110  can have a proximal end  112 , a distal end  114 , and a lumen extending axially through the outer tube  110  between the proximal and distal ends  112  and  114 . The proximal end  112  of the outer tube  110  can be configured to fit snugly into the hub  130 . The outer tube  110  can be made from a rigid material (e.g., stainless steel, extrudable plastics such as polypropylene or polyethylene, or other commonly used, surgically safe machinable metals), which can provide sufficient structural support to allow a user to readily maneuver the distal end  114  to the intended application area. The outer tube  110  can have a length between about 7 cm and about 67 cm. In some embodiments, for example, the outer tube  110  can have a length between about 7 and about 27 cm (e.g., for open procedures), between about 30 and about 40 cm (e.g., for general procedures), or between about 57 and about 67 cm (e.g., for bariatric procedures). In some embodiments, the outer tube  110  can have a length between about 33 and about 43 cm. In addition, the outer tube  110  can be configured to fit through a trocar or surgical opening. Thus, the exterior diameter of the outer tube  110  can be limited by the dimensions of the trocar or opening created for the procedure. In some embodiments, for example, the outer tube  110  can have an external diameter between about 4 mm and about 10 mm (e.g., between about 4 and about 6 mm, between about 5 and about 7 mm, between about 6 and about 8 mm, between about 7 and about 9 mm, or between about 8 and about 10 mm). In some embodiments, the exterior diameter of the outer tube  110  can be between about 4 and about 5 mm. Further, the lumen of the outer tube  110  can have a diameter between about 2 mm and about 9 mm (e.g., between about 2 and about 4 mm, between about 3 and about 6 mm, or between about 5 and about 7 mm). In some embodiments, for example, the lumen of the outer tube  110  can have a diameter between about 3 and about 4 mm. Typically, the lumen of the outer tube  110  can have a diameter that is coincident or slightly greater than the outer diameter of the inner tube  120 . 
         [0033]    Referring now to  FIGS. 3A and 3B , the hub  130  can have a proximal end  132 , a distal end  133 , and an interior surface  135  defining a lumen that extends axially between the proximal and distal ends  132  and  133 . The interior surface  135  can define a proximal cavity  136 , a distal cavity  137 , and a circumferential protrusion  138  that can define the boundaries of the proximal and distal cavities  136  and  137 . The distal cavity  137  can be configured to receive the proximal end  112  of the outer tube  110 , which can be secured within the distal cavity  137  using a suitable means (e.g., a laser weld or a press fit, or with an adhesive such as an epoxy). The hub can be made from, for example, stainless steel, machinable plastics such as polypropylene or polyethylene, or surgically safe, machinable metal. The length of the hub  130  between the proximal end  132  and the distal end  133  can be sufficient to effectively secure the outer tube  110  to the distal end  133  and create an interface at the proximal end  132  for the attachment of the connector fitting  140 . For example, in some embodiments, the hub  103  can have a length between about 1 cm and about 6 cm. In some embodiments, the length of the hub  130  can be between about 1 and about 3 cm, between about 2 and about 4 cm, or between about 4 and about 6 cm. In some cases, the hub  130  can have a length between about 1 and about 2 cm, or between about 2 and about 3 cm. Since the distal cavity  137  can be configured to receive the proximal end  112  of the outer tube  110 , diameter of the distal cavity  137  can be dependent on the external diameter of the outer tube  110 , such that it is slightly greater than the external diameter of the outer tube  110 . In some embodiments, the diameter of the distal cavity  137  can be between about 5 mm and about 14 mm (e.g., between about 5 and about 8 mm, between about 6 and about 9 mm, between about 7 and about 10 mm, between about 8 and about 11 mm, between about 9 and about 12 mm, between about 10 and about 13 mm, or between about 11 and about 14 mm). 
         [0034]    The interior surface  135  of the proximal cavity  136  can be tapped to define threading  139 . The threading  139  within the hub  130  can provide a junction for the connector fitting  140 . The connector fitting  140  can have, for example, threading  142  (e.g., 1/4-28 UNF threading) to mate with the threading  139  within the hub  130 , and a female fitting  144  to mate with a vessel containing a material to be applied. The connector fitting  140  can be attached to the hub  130  using, for example, the threading, first adhesive  160  (e.g., medical grade cyanoacrylate, epoxy, or another suitable adhesive), or any other appropriate type of interface. The female connector fitting  144  can allow any vessel (e.g., a syringe) to be attached to the device  100 . 
         [0035]    Within the outer tube  110  is the inner tube  120 , embodiments of which are shown in the cross-sectional views of  FIGS. 4A-4C . The inner tube  120  can have a proximal end  121  and a distal end  122  (shown in  FIG. 1B , for example), and can have one, two, three, four, or more than four lumens extending axially between the proximal and distal ends  121  and  122 . As shown in  FIGS. 4A-4C , for example, the inner tube  120  can have a core  123  and a lumen  124  ( FIG. 4A ), or a core  123  and lumens  124  and  125  arranged around the core  123  ( FIG. 4B ), or a core  123  and lumens  124 ,  125 ,  126 , and  127  arranged around the core  123  ( FIG. 4C ). The presence of more than one lumen can allow a fluid (e.g., a viscous surgical fluid such as a sealant) to flow through the device  100  in a restricted manner, thus limiting the amount of fluid applied. Restriction of flow can be dependent on the cross sectional area of the lumens, for example. The multiple lumens also can facilitate uniform application of the fluid over a desired area, and can minimize clogging by preventing sealant from curing within the lumens. If one lumen becomes clogged, pinched, or occluded, the fluid can flow through the remaining lumens. 
         [0036]    The length of the inner tube  120  can be dependent on the length of the outer tube  110 . For example, the inner tube  120  can have a length between about 18 cm and about 68 cm. In some embodiments, the inner tube  120  can have a length between about 18 and about 28 cm, between about 28 and about 38 cm, between about 38 and about 48 cm, between about 48 and about 58 cm, or between about 58 and about 68 cm. In some embodiments, the inner tube  120  can have a length between about 35 and about 45 cm. 
         [0037]    In addition, the inner tube  120  can be configured to fit through the lumen of the outer tube  110 . Thus, the external diameter of the inner tube  120  can be coincident or slightly smaller than the inner diameter of the outer tube  110 . In some embodiments, the inner tube  120  can have an external diameter between about 2 mm and about 7 mm (e.g., between about 2 and about 4 mm, between about 3 and about 5 mm, between about 4 and about 6 mm, or between about 5 and about 7 mm). In some embodiments, for example, the inner tube  120  can have an exterior diameter between about 2 and about 3 mm, or between about 3 and about 4 mm. In general, the inner tube  120  can have a length that is slightly longer than that of the outer tube  110 , such that when the inner tube  120  is placed within the lumen of the outer tube  110 , the proximal end  121  of the inner tube  120  extends beyond the proximal end  112  of the outer tube  110 , and the distal end  122  of the inner tube  120  extends beyond the distal end  114  of the outer tube  110 . For example, when the proximal end  121  of the inner tube  120  and the proximal end  122  of the distal end  122  are positioned within the proximal and distal cavities  136  and  137  of the hub  130 , the inner tube  120  can extend about 0.5 cm to about 5 cm (e.g., between about 0.5 and about 2 cm, between about 1 and about 3 cm, between about 2 and about 4 cm, or between about 3 and about 5 cm) beyond the distal end  114  of the outer tube  110 . It is to be noted that the overall length of the distal end  122  of the inner tube  120  extending beyond the distal end  114  of the outer tube  110  can be adjusted based on the procedure. 
         [0038]    The inner tube  120  generally is flexible, and can be made from any of a variety of suitable materials, including polyether block amide formulations, soft polyurethanes (e.g., PELLETHANE® 2363-80AE; Lubrizol Advanced Materials, Inc., Cleveland, Ohio), and soft polyvinylchloride (PVC) materials. In some embodiments, for example, the inner tube  120  can be made of the polyether block amide PEBAX® 3533 SA01 MED (Arkema Specialty Polyamides, France). 
         [0039]    The core  123  of the inner tube  120  can contain a co-extruded wire  128 , which can allow a user to bend the distal end  122  of the inner tube  120  into a desired position. As depicted in  FIGS. 5A and 5B , for example, the distal end  122  of the inner tube  120  can extend beyond the distal end  114  of the outer tube  110 , and the wire  128  can be bent by a user to direct the distal end  122  to a desired target within a body. The central position of the co-extruded wire  128  in the core  123  of the inner tube  120  can allow for equal bending of the distal end  122  in any direction. The co-extruded wire can be made from stainless steel, or from any other thin gage, surgically safe metal. The diameter of the wire  128  can be determined at least in part by the outer diameter of the inner tube  120 . For example, the wire  128  can have a diameter of about 0.5 mm to about 2 mm (e.g., between about 0.5 and about 1 mm, between about 1 and about 1.5 mm, or between about 1.5 and about 2 mm). The wire  128  can have a length that is essentially the same as the length of the inner tube  120  (e.g., between about 7 cm and about 67 cm). It is to be noted that the end of the wire  128  at the distal end  122  of the inner tube  120  can be trimmed back by about 0.3 to about 2 mm (e.g., about 0.3, 0.5, 0.7, 0.9, 1, 1.3, 1.6, or 2 mm) so that the wire  138  does not come into contact with bodily tissues or organs during use, thus reducing the risk of damage to tissue during application of a surgical fluid within a patient, for example. 
         [0040]    As shown in  FIGS. 6A and 6B , the proximal end  121  of the inner tube  120  can be secured within the hub  130  by the collar  150 . In some embodiments, the collar can be a one-sided part, which can facilitate assembly of the device  100 , and can create a seal within the hub  130 . The proximal end  121  of the inner tube  120  can be affixed to the collar  150  using the second adhesive  170  (e.g., a UV curable adhesive, epoxy, or cyanoacrylate). 
         [0041]    In some embodiments, during manufacturing and assembly of the device  100 , the hub  130  can be attached (e.g., welded) to the proximal end  112  of the outer tube  110 , the collar  150  can be adhered to the inner tube  120  (e.g., using an adhesive), and the distal end  122  of the inner tube  120  can then be passed through the hub  130  and the outer tube  110 , until the collar  150  comes into contact with the circumferential protrusion  138  of the hub  130 . The connector fitting  140  then can be installed via the threading  139  and the first adhesive, for example. 
         [0042]    In use, the distal tip  122  of the inner tube  120  can be manipulated manually or mechanically (e.g., using a grasper device inserted into the surgical field), until the distal tip  122  achieves a desired configuration. The distal tip  122  can retain its shape until it is again manipulated by a user. A vessel (e.g., a syringe) containing a sealant or other surgical fluid can be attached to the connector fitting  140 , and the vessel can be actuated to pass a sealant or other fluid through the device  100 . In addition to being useful with open bowel anastomosis procedures, the devices provided herein may be useful for endoscopic approaches to other sites in the gastrointestinal tract, such as the stomach (e.g., for obesity surgeries) or the esophagus, for example. Thus, in some embodiments, the devices and methods provided herein can be useful as an adjunct to closure of anastomotic junctions in the gastrointestinal tract. In some embodiments, the devices and methods provided herein also can be useful in arthroscopic procedures. 
       Other Embodiments 
       [0043]    It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims.