Sheath for gastrostoma, sheathed dilator, sheath for gastrostoma with insertion aid, gastrostomy catheter kit, and method of splitting sheath for gastrostoma

Abstract

The present invention provides a sheath for gastrostoma ( 1 ), a sheathed dilator, a gastrostomy catheter kit and a method of splitting a sheath for gastrostoma. The sheath for gastrostoma ( 1 ) includes a sheath body ( 11 ) in which a gastrostomy catheter ( 2 ) is inserted and a handle ( 12 ). The sheath for gastrostoma ( 1 ) lowers the insertion resistance of a gastrostomy catheter when inserted in a fistula before insertion of the gastrostomy catheter in the fistula for replacement in the patient's body. According to the invention, a sheath for gastrostoma, a sheathed dilator, a sheath for gastrostoma with insertion aid, a gastrostomy catheter kit and a method of splitting a sheath for gastrostoma which can lower the insertion resistance during placement of a catheter in the patient's body, facilitate air supply control of an endoscope and stabilize endoscopic visual field during surgery are provided.

1 . A sheath for gastrostoma comprising:
 the sheath for gastrostoma used for gastrostomy and replacement of the gastrostomy catheter in which a gastrostomy catheter is inserted in a fistula for placement, the gastrostomy catheter including a tubular section which includes an inner path for introducing a nutrient or a chemical into the stomach from outside of the body, and an indwelling section attached to a distal section of the tubular section and formed as a dome protruding radially outward of the tubular section, the indwelling section being able to reduce its diameter by an extending force applied by an obturator, which is used to extend the indwelling section:   a cylindrical sheath body in which the gastrostomy catheter is inserted; and   a handle provided to protrude at one longitudinal end of the sheath body.   
     
     
         2 . The sheath for gastrostoma according to  claim 1 , further comprising:
 a lid which is provided pivotably via a hinge section at a base end of the sheath body which is an end at the side of the handle and is disposed in an inner path which is a through-hole defined inside the sheath body, the lid opening and closing the inner path of the sheath body through pivotation about the hinge section, wherein:   the sheath body is provided with a lid abutting section against which the lid is made to abut at a distal end which is an end opposite to the base end of the sheath body through pivotation about the hinge section; and   the lid is made to abut against the lid abutting section in its closed position where the lid closes the inner path and is pivoted from the closed position toward the distal section of the sheath body to release the inner path.   
     
     
         3 . The sheath for gastrostoma according to  claim 2 , wherein the lid abutting section is provided in the sheath body at a side opposite to the hinge section across the inner path and an end of the lid opposite to the side of the hinge section abuts against the lid abutting section. 
     
     
         4 . The sheath for gastrostoma according to  claim 2 , wherein the handle is pivotably provided at the base end of the sheath body via the hinge section, and the lid is provided to protrude in the inner path from the handle to open and close the inner path of the sheath body through integrated pivotation with the handle. 
     
     
         5 . The sheath for gastrostoma according to  claim 2 , wherein the hinge section is an elastic support member which elastically supports the lid at the closed position while allowing pivotation of the lid from the closed position in an open direction. 
     
     
         6 . The sheath for gastrostoma according to  claim 2 , further comprising:
 an elastic member which functions as an elastic support member that applies an urging force to the handle so as to elastically support the lid at the closed position while allowing pivotation of the lid from the closed position in an open direction.   
     
     
         7 . The sheath for gastrostoma according to  claim 1 , further comprising:
 a lid which is provided in the handle via the lid hinge section and disposed in the inner path which is a through-hole defined in the sheath body, wherein:   the handle is provided pivotably at the base end which is an end at the side of the handle of the sheath body via a hinge section other than the lid hinge section; and   the lid is disposed in its closed position at which the lid closes the inner path and is able to open and close the inner path of the sheath body through pivotation about the lid hinge section.   
     
     
         8 . The sheath for gastrostoma according to  claim 7 , wherein:
 the sheath body is provided with a lid abutting section against which the lid is made to abut at a distal end which is an end opposite to the base end of the sheath body through pivotation about the hinge section; and   the lid is made to abut against the lid abutting section in its closed position where the lid closes the inner path and is pivoted from the closed position toward the distal section of the sheath body to release the inner path.   
     
     
         9 . The sheath for gastrostoma according to  claim 8 , wherein the hinge section and the lid hinge section are provided in the sheath body at a side opposite to the lid abutting section across the inner path and an end of the lid at the side opposite to the lid hinge section is made to abut against the lid abutting section. 
     
     
         10 . The sheath for gastrostoma according to  claim 7 , wherein:
 the lid hinge section is disposed at an end of a stopper projection piece which is provided to protrude from the handle, inserted in the sheath body and is disposed along an inner surface of the sheath body at a side opposite to the lid abutting section across the inner path; and   when the lid receives a force to cause the same to pivot from the closed position in an open direction, the stopper projection piece is pressed against the inner surface of the sheath body to restrict pivotation of the stopper projection piece with respect to the sheath body.   
     
     
         11 . The sheath for gastrostoma according to  claim 10 , wherein the stopper projection piece is made of a material with rubber elasticity. 
     
     
         12 . The sheath for gastrostoma according to  claim 7 , wherein the lid hinge section is made of a material with rubber elasticity and constitutes a lid elastic support member for elastically supporting the lid at the closed position. 
     
     
         13 . The sheath for gastrostoma according to  claim 7 , wherein the lid hinge section and the lid are formed from a material with rubber elasticity. 
     
     
         14 . The sheath for gastrostoma according to any one of  claims 7  to  13 , wherein a mounting section which constitutes a part of the handle, the lid hinge section and the lid is formed from synthetic resin. 
     
     
         15 . The sheath for gastrostoma according to  claim 2 , wherein a recess for housing the lid is formed on an inner surface of the inner path of the sheath body. 
     
     
         16 . The sheath for gastrostoma according to  claim 15 , wherein an expanded section is provided at the base end of the sheath body, the expanded section being formed so that the sheath body is expanded radially outward, wherein the recess for housing the lid is a space provided so as to extend the inner path toward the inside of the expanded section. 
     
     
         17 . The sheath for gastrostoma according to  claim 1 , wherein a handle main piece which constitutes a part or all of the handle, the sheath body and the hinge section is formed integrally as one component from synthetic resin. 
     
     
         18 . The sheath for gastrostoma according to  claim 1 , wherein a grasping ring is provided at a side opposite to the hinge section of the handle to allow a user to insert finger (s) for grasping. 
     
     
         19 . The sheath for gastrostoma according to  claim 1 , wherein one or more notch sections are formed which facilitate vertical splitting of the sheath body in a longitudinal direction. 
     
     
         20 . The sheath for gastrostoma according to  claim 19 , wherein the notch section is a notched groove formed in the sheath body so as not to penetrate the sheath body in the thickness direction, and an uncut portion is provided by locally reducing the thickness of the sheath body at a bottom side of the notched groove. 
     
     
         21 . The sheath for gastrostoma according to  claim 20 , wherein the sheath body includes a V-shaped distal notch section configured to recess from an end surface at the base end of the sheath body and the notched groove is formed to extend toward a distal end of the seal body from a depth section of the distal notch section. 
     
     
         22 . The sheath for gastrostoma according to  claim 19 , wherein:
 the notch section is a slit formed to extend along the longitudinal direction of the sheath body, the slit being formed at a part along the longitudinal direction of the sheath body and being shorter than the entire longitudinal direction length of the sheath body; and   the sheath body has an uncut portion at which no slit is formed along a virtual extended line of the slit.   
     
     
         23 . The sheath for gastrostoma according to  claim 20 , wherein a load applied to the inner surface of the sheath body is not smaller than 0.5N to not greater than 5N in order to fracture at least one of the uncut portions. 
     
     
         24 . The sheath for gastrostoma according to  claim 19 , wherein the notch section is formed in a wedge-shaped cross-section with its opening width increasing from an inner surface toward an outer surface of the sheath body. 
     
     
         25 . The sheath for gastrostoma according to  claim 19 , wherein the notch section is formed through a laser processing of the sheath body. 
     
     
         26 . The sheath for gastrostoma according to  claim 25 , wherein the sheath body is made of a FEP-containing material and a portion of the sheath body where the notch section has been formed is whitened by the laser processing. 
     
     
         27 . The sheath for gastrostoma according to  claim 19 , wherein the handle is provided at a position where the handle does not interfere with the notch section in a circumferential direction of the sheath body. 
     
     
         28 . The sheath for gastrostoma according to  claim 27 , wherein the notch section is formed only at one position along the circumferential direction of the sheath body and only one handle is provided. 
     
     
         29 . The sheath for gastrostoma according to  claim 1 , wherein the sheath body is oriented in the longitudinal direction thereof. 
     
     
         30 . The sheath for gastrostoma according to  claim 1 , wherein an end surface of the sheath body at the side of the base end is inclined with respect to an axial center of the sheath body. 
     
     
         31 . The sheath for gastrostoma according to  claim 1 , wherein an inner diameter of the sheath body is larger than an outer diameter of the tubular section of the gastrostomy catheter. 
     
     
         32 . The sheath for gastrostoma according to  claim 1 , wherein the material of the sheath body contains fluororesin. 
     
     
         33 . The sheath for gastrostoma according to  claim 32 , wherein the fluororesin comprises any one of PTFE, ETFE and FEP. 
     
     
         34 . The sheath for gastrostoma according to  claim 1 , wherein the sheath body can be removably disposed outside of a dilator used for forming a fistula. 
     
     
         35 . The sheath for gastrostoma according to  claim 34 , wherein the dilator includes a guidewire path which penetrates the dilator in the longitudinal direction. 
     
     
         36 . The sheath for gastrostoma according to  claim 34 , wherein the dilator has a scale on a peripheral surface thereof for measurement of a distance between an inner stomach wall and an outer body surface. 
     
     
         37 . The sheath for gastrostoma according to  claim 36 , wherein the sheath body has transparency that enables the scale of the dilator to be viewed from outside. 
     
     
         38 . The sheath for gastrostoma according to  claim 34 , wherein the dilator has a narrow-diameter dilator and a large-diameter dilator which are integrated together, the narrow-diameter dilator including the guidewire path inside thereof and the large-diameter dilator being disposed outside of the narrow-diameter dilator and assembled to the narrow-diameter dilator. 
     
     
         39 . The sheath for gastrostoma according to  claim 1 , wherein an inner diameter of the sheath body is smaller than the maximum outer diameter of the indwelling section of the gastrostomy catheter which adopts a reduced-diameter state due to the extending force applied by the obturator. 
     
     
         40 . The sheath for gastrostoma according to  claim 39 , wherein the sheath body is vertically splittable when the gastrostomy catheter is inserted with the indwelling section being in its reduced-diameter state by the obturator. 
     
     
         41 . The sheath for gastrostoma according to  claim 1 , wherein the sheath body is formed of a stretch-deformable material and is thus radially expandable. 
     
     
         42 . The sheath for gastrostoma according to  claim 1 , wherein an inner diameter of the sheath body is larger than the maximum outer diameter of the indwelling section of the gastrostomy catheter which adopts a reduced-diameter state due to the extending force applied by the obturator. 
     
     
         43 . The sheath for gastrostoma according to  claim 1 , wherein the sheath body is configured such that a sheath insertion aid having a rod-shaped appearance can be inserted in the sheath body and the sheath insertion aid includes a rod-shaped body and a tapered distal section having a tapering configuration provided to protrude at one longitudinal end of the rod-shaped body. 
     
     
         44 . The sheath for gastrostoma according to  claim 43 , wherein the sheath insertion aid includes a guidewire insertion hole which penetrates the sheath insertion aid along the longitudinal direction. 
     
     
         45 . The sheath for gastrostoma according to  claim 43  or  44 , wherein the sheath insertion aid can function as a dilator used for forming a fistula. 
     
     
         46 . A sheathed dilator in which the sheath for gastrostoma according to  claim 1  is disposed outside the dilator used for forming a fistula. 
     
     
         47 . A sheath for gastrostoma with insertion aid in which a sheath insertion aid is inserted in the sheath body of the sheath for gastrostoma according to  claim 1 ,
 the sheath insertion aid being provided to protrude at a tapered distal section having a tapering configuration at one longitudinal end of a rod-shaped body.   
     
     
         48 . A gastrostomy catheter kit, comprising:
 a gastrostomy catheter for percutaneously feeding a nutrient or a chemical into the patient's stomach from outside of the body; an obturator; and one of the sheath for gastrostoma according to  claim 1  and the sheathed dilator according to  claim 46 , wherein:   the gastrostomy catheter includes a tubular section which includes an inner path for introducing a nutrient or a chemical into the stomach from outside of the body, and an indwelling section which is attached to a distal section of the tubular section and is formed as a dome protruding radially outward of the tubular section, in which the indwelling section can reduce its diameter due to the extending force applied by an obturator for extending the indwelling section;   the gastrostomy catheter in which an indwelling section in its reduced-diameter state by the obturator is inserted in a sheath for gastrostoma of the sheath for gastrostoma according to  claim 1  and a sheath for gastrostoma of the sheathed dilator according to  claim 46  while the sheath for gastrostoma is inserted in a fistula.   
     
     
         49 . The gastrostomy catheter kit according to  claim 48 , wherein:
 the obturator includes an outer case, a pushing rod for extension which includes a rod body inserted in the outer case to be movable in a longitudinal direction of the outer case and a stopper for anchoring the gastrostomy catheter to the outer case; and   in a state in which the gastrostomy catheter is anchored to the outer case with the stopper, an operator inserts a distal end of the pushing rod for extension protruding from the outer case of the rod body in the indwelling section of the gastrostomy catheter and presses the most distal section of the indwelling section so as to extend the indwelling section.   
     
     
         50 . The gastrostomy catheter kit according to  claim 48 , wherein the gastrostomy catheter and the obturator include a guidewire path and the obturator is configured to reduce the diameter of the indwelling section of the gastrostomy catheter in a state in which the obturator is disposed outside of the guidewire which is inserted in the gastrostomy catheter. 
     
     
         51 . The gastrostomy catheter kit according to  claim 48 , further comprising:
 the sheath for gastrostoma according to any one of  claims 1  to  45  as a sheath for gastrostoma used for replacement, wherein the gastrostomy catheter in which the indwelling section is in its reduced-diameter state by the obturator is inserted in the sheath for gastrostoma.   
     
     
         52 . The gastrostomy catheter kit according to  claim 51 , further comprising:
 the sheath for gastrostoma with insertion aid according to  claim 47  configured by using the sheath for gastrostoma used for replacement.   
     
     
         53 . A method of splitting a sheath for gastrostoma, comprising splitting one or more parts of a sheath body in a circumferential direction along the entire longitudinal direction length of the sheath body by inserting, in a sheath body of the sheath for gastrostoma according to any one of  claims 1  to  45 , a medical device having an outer diameter larger than an inner diameter of the sheath body. 
     
     
         54 . The method of splitting a sheath for gastrostoma according to  claim 53 , wherein the medical device is a gastrostomy catheter of which the indwelling section is in its reduced-diameter state due to the extending force from the obturator, and the maximum outer diameter of the indwelling section which adopts a reduced-diameter state due to the extending force applied by the obturator is larger than an inner diameter of the sheath body.