JPH0638972A - Cannula needle - Google Patents

Abstract

PURPOSE:To provide a cannula needle which enables the insertion of a medical apparatuses with various shapes of curving and bending through a pallial tube stuck and retained in a body wall of a patient, the preventing of leak of a positive pressure gas in a body cavity and damage to an organ during the sticking thereof and the fixing of the pallial tube on the body wall. CONSTITUTION:In a body part 4 of a pallial tube which comprises an inner needle (a) and the pallial tube (b), a spiral body 12 is arranged between an inner layer 10 and an outer layer 11. An internally elastic bag 14 which comprises a flexible tube body reinforced by injecting a sealing material 13 into a gap thereof and is provided on an internal wall near a base end part 5 can be expanded by a gas or the like being sent from a branch tube 7. An elastic bag is provided on the external surface of the pallial tube to be retained and fixed on a body wall.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention punctures the body surface of a patient,
The present invention relates to a trocar for inserting an outer tube by inserting it into a body wall and inserting an endoscope, an inspection instrument, a surgical treatment instrument or the like through the tube.

[0002]

2. Description of the Related Art In recent years, a surgical method has been widely used in which a trocar is punctured on the body surface of the abdomen, chest, etc. to place an outer tube, and a laparoscope or a thoracoscope is inserted from there to perform an examination or an operation. It is taking place. As a trocar needle used in such an operation, a trocar that is generally used can be inserted into and removed from the outer tube inserted into the body wall from the body surface and left indwelling, and the lumen of the outer tube. The sharp tip for easy insertion into the body surface,
And an inner needle having a handle for grasping and pressing outside the body.

Such an outer needle is provided with a valve mechanism, and gas blown in order to secure a operative field by making a positive pressure in the body cavity leaks from a gap between the inserted medical instrument and the outer tube. Then, it is general to prevent the positive pressure from being released. A slide type opening / closing device or an flutter opening / closing device (Japanese Patent Laid-Open No. 1-209056) that can be freely opened / closed by an operator is adopted, but since many mechanically accurate parts are used, the manufacturing cost is high. Becomes higher,
There is a problem that it is difficult to maintain airtightness for various inserts having different cross-sectional shapes.

[0004] As another idea, means for forming a valve mechanism by inflating an internal balloon (Abstracts of the First Endoscopic Surgery Research Society, page 22, (3.3.
2)) is proposed. According to this report, it is reported that the force-tightness is not impaired even if forceps or clips whose shaft shape is not a perfect circle are used. However, the molded product at the proximal end of the outer tube has an inflating member that bulges inward. Has been. Inward bulging during balloon deflation increases resistance to the insert, and since the proximal end of the valve mechanism is positioned on the body surface so as to join the outer tube body, it can be used for sharply curved inserts. However, there is a problem of forming unnecessary straight portions.

The outer tube is generally made of a rigid material such as metal. On the other hand, since a rigid endoscope such as a laparoscope or a treatment instrument that has been conventionally used has a linear shape, the user has not felt any trouble so far even if it is rigid. However, in view of the current situation in which surgical operation has been attempted through the mantle tube even in cases in which various surgical instruments such as forceps having a curved or bent shape suitable for the operative field have been conventionally performed by laparotomy. With the treatment tools such as forceps and clips designed under the dimensional constraint that they can be inserted within the range of the inner diameter of the rigid tube, dissatisfaction with the surgical operation has come to be seen.

As a manifestation of this, the above-mentioned report using the balloon system proposes a flexible silicon soft trocar for the outer tube itself. As a result,
It became possible to insert curved forceps, and it was less likely to cause damage due to the operation of excluding the liver. However, in order to maintain the shape of the mantle tube against the axial body wall puncture resistance and the compression force of the surrounding tissues, it is inevitable that the wall thickness is increased to some extent in terms of strength, and the puncture hole is enlarged or There is a problem of increasing the invasion of the patient, such as the need for a small incision in advance.

Further, as a safety device for preventing unnecessary damage caused by hitting internal organs when the tip portion of the inner needle punctures into the body cavity, a sleeve having a spring mechanism on the proximal side is used as a safety device. In preparation for the outer circumference, when the resistance to piercing the body wall has decreased,
That is, a mechanism has been devised to protect the inner needle tip portion by protruding the sleeve when the inner needle tip portion punctures into the body cavity (JP-A-2-65854). It is popular because it allows the surgeon to insert it with peace of mind, but since this has a mechanism in which the sleeve slides in the gap between the inner needle and the outer tube, it is desirable that the outer tube be rigid and highly accurate. There is a cost problem that requires various parts.

The mantle tube placed on the body wall is
Since instruments such as an endoscope and forceps are frequently pulled out and replaced, a means for securely fixing them to the body wall and preventing natural deviation during surgery is required. As an example of the means, a member has been disclosed in which a trocar is inserted into the body surface, and a helical projection provided on the proximal end of the outer tube is twisted and fixed to body wall tissue (clinical surgery). , 46 (8), 943 to 953 (199
1)). Although this method is highly evaluated for its certainty, it has a problem of significantly damaging body wall tissue. As another method, it is disclosed that an elastic member that comes into contact with and fixes to the inner wall surface of the insertion hole is inflated as a balloon (Japanese Utility Model Publication No. 2-17105). This method is excellent in that it can be airtightly fixed without sharply damaging the body wall tissue, but bulging from the outer wall of the trocar is inevitable, and there is a problem that the resistance to trocar needle insertion increases. .

[0009]

SUMMARY OF THE INVENTION The present invention has been made as a result of various studies in order to solve the above-mentioned problems associated with a trocar, and the object of the present invention is to determine the surgical field. It has a flexibility to insert treatment tools such as various curved and bent forceps, prevents gas leakage from body cavity and damage to internal organs at the time of puncture, reduces puncture resistance, and ensures safety. An object of the present invention is to provide a trocar that can fix an outer tube to a body wall.

[0010]

A trocar according to the present invention for achieving the above object is formed so as to be inserted into and removed from an outer tube inserted into and fixed to a body wall and an inner cavity of the outer tube. And a trocar consisting of an inner needle having a puncture portion at the tip and a grip portion at the rear end, wherein the outer cannula has a bendable flexible main body portion reinforced with a spiral body, and a collar. An inner elastic bag that is bulged on the inner surface near the base end of the main body,
A branch pipe A in gas-liquid communication with the inner elastic bag is provided in the pipe wall near the base end portion, and the branch pipe A is branched at the rear surface of the base end portion.

Further, an expanding / contracting portion is provided near the tip of the outer tube body so as to extend and contract a helical body contained in the tube wall in the longitudinal direction, or near the tip of the outer tube body. And / or an outer elastic bag capable of bulging is provided on the outer surface in the vicinity of the base end, and a branch pipe B in gas-liquid communication with the outer elastic bag is provided in the pipe wall of the main body. It is characterized by branching on the rear surface of the end.

The present invention will be described in detail below with reference to the illustrated embodiments. FIG. 1 is a diagram showing an entire trocar needle according to an embodiment of the present invention, FIG. 2 is a diagram for explaining an inner elastic bag provided in the vicinity of a proximal end portion of an outer tube, and FIG. 3 is a diagram showing an outer tube. FIG. 4 is a view for explaining the expansion / contraction portion formed near the tip portion, and FIG. 4 is a view for explaining the outer elastic bag provided on the outer surface of the outer tube.

The trocar according to the present invention comprises an outer tube comprising a main body (4), a tip (6) and a collar-shaped base (5) as shown in FIG. Basically, the inner needle has a puncture portion (needle tip 1) at the tip and a grip portion (handle 3) at the rear end as shown in a). FIG. 1 (c) shows a branch tube (7) which is inserted from the inner needle of the mantle tube and emerges from the proximal end.
1 shows an overview of the entire trocar with a pilot balloon (8) and a check valve (9) attached.

The inner needle has a sharp puncture portion (needle tip 1) which serves as a puncture and puncture portion at the tip of the needle body (2) and has a handle (3) which serves as a grip portion at the rear end. , It may be one that has been used conventionally, and is not particularly new. The size depends on the thickness of the body wall of the site to which it is applied, the outer diameter and the effective length of the instrument used, and in the case of the abdomen, for example, the needle tip (1) and the needle body (2 The outer diameter of () is 3 to 20 mm, and the length up to the base of the handle (3), that is, the effective length of the mantle tube is suitably 40 to 200 mm.

The needle tip (1) has a sharp cutting edge at the tip such as a polygonal cone having one to a plurality of slopes such as an arrowhead, or a conical shape, and has a sharpness for piercing living tissue such as skin or muscle layer. Is required. However, when using a large diameter outer tube, a needle tip with a large outer diameter is inevitably necessary, and in this case it is difficult to puncture and insert with only the needle tip, so the body surface Sometimes a puncture is made after incising a part of the. In the method of use premised on such a body surface incision, the needle tip does not necessarily need to be sharp, and a hemispherical rounded shape may be preferred in order to protect a body cavity organ. As the material of the needle tip, metals such as stainless steel, titanium alloy, and aluminum alloy are generally used.

The needle body (2) may be integrally formed of the same material as the needle tip (1), but may be made separately from the needle tip and joined as shown in FIG. In that case, even if it is the same metal material as the needle tip, it can be made lightweight by making it into a hollow pipe shape, and it is also possible to use ABS resin, polycarbonate resin, nylon resin, hard vinyl chloride resin, polysulfone resin, etc. It can also be made of rigid hard plastic or ceramic material.

The handle (3) may have various shapes such as a cylindrical shape having an outer diameter of 30 to 80 mm, a spherical shape, an elliptical shape, or a cubic shape, but the handle (3) has such a size and shape that it can be easily held in the palm of the operator. There is a need. Normally, it is grasped together with the proximal end portion (5) of the mantle tube and strongly pressed against the body surface, so that it is thicker than the inner diameter of the proximal end portion (5) so as to catch the mantle tube that is pushed back by puncture resistance and retracts. It is necessary to provide the abutment surface at its root. The material of the handle (3) is not particularly limited. The needle tip (1) and the needle body (2) may be integrally formed of the same material, or may be made of different materials and assembled, but injection molding of hard plastic is relatively inexpensive. It is preferable because it can be manufactured.

Next, the outer tube has an inner layer (10) and an outer layer (1).
1), a spiral body (12) is arranged, and the void is filled with an encapsulating material (13), and a tip (6) is provided at the tip and a collar-like body is provided at the rear end of the body (4). The base part (5) is connected, and the main body part (4) has a bendable flexibility, and has a structure in which an inner needle can be inserted into and removed from the inlet of the base part (5) in its lumen. There is. Then, the inner layer (10) is separated from the layer of the encapsulating material (13) in the vicinity of the base end portion (5) to form the inner elastic bag (14), and the inner elastic bag (14) and the encapsulating material (13). The distal end of the branch pipe (7), which serves as a narrow passage for gas-liquid flow for inflating and contracting the inner elastic bag (14), is inserted and attached to the gap between the two.

The outer tube has a lumen diameter of 3 to 20 mm and a total length of 40 to 200 mm, and is selected according to the thickness of the body wall at the site to be treated, the shaft outer diameter of the surgical instrument to be used, the effective length and the like.
With the inner needle attached as shown in FIG. 1 (c), the distance from the position where the slope forming the cutting edge of the needle tip (1) ends to the tip surface of the tip (6) is about 0 to 10 mm. It is appropriate to do so, and the shorter one is preferable in order to avoid piercing into the body cavity to a depth more than necessary. Further, the outer diameters of the tip (6) and the main body (4) determine the substantial puncture hole in the body wall, so if the lumen diameter of the mantle tube is the same, the degree of invasiveness to living tissue is reduced. In order to reduce the thickness, it is desirable that the thickness is thin, and therefore the thickness is preferably 3 mm or less.

The tip (6) has a thin tip in order to reduce puncture resistance at the time of puncture, and preferably has a rounded tip so as not to damage a body cavity organ, and the tip (1) ) And a small gap is desired. Further, the rear end side is sandwiched between the inner layer (10) and the outer layer (11), and the spiral body (12) is formed.
And / or has a connecting part for connecting with the encapsulating material (13),
Adhesive fixed. Furthermore, it is preferable that both the inner and outer surfaces of the connecting portion are smoothly finished so that unnecessary insertion resistance and frictional resistance with the inner needle do not occur.

The base portion (5) has a collar portion projecting from the outer periphery of the main body portion (4) by 5 to 20 mm, and its plane shape is circular,
It may have various shapes such as an ellipse and a rectangle, but as described above, the shape is not particularly limited as long as it can be easily accommodated in the operator's palm together with the handle (3) of the inner needle, and its thickness is 3 to 8 mm. It is a degree. Also, on the tip side, the main body (4)
Sandwiched between the inner layer (10) and outer layer (11) of the spiral body (1
2) It has a connecting part for connecting with and is fixedly adhered to these. The overall length should be as short as possible,
It is preferable that the opening of the rear end surface of the proximal end portion (5) be chamfered in a tapered shape or a rounded shape so that the inner needle can be easily inserted.

The tip (6) is required to have hardness and elasticity so that it is not easily rolled up and deformed due to piercing resistance.
In addition, the base end portion (5) is required to have shape retention and hardness that can maintain a puncture hole against contraction pressure from the surrounding body wall and can serve as a gripping portion for postoperative removal. As materials for the tip (6) and the base (5) that can meet such requirements, general-purpose hard resins such as hard vinyl chloride resin, ABS resin, and polycarbonate resin, or soft vinyl chloride resin, polyurethane resin, polyethylene A general-purpose flexible resin such as resin, silicone rubber or natural rubber can be used, and can be easily molded by cutting, injection molding, compression molding or the like.

Next, the main body portion (4) is composed of the inner layer (10), the outer layer (11), the spiral body (12), and the encapsulating material (13) as described above. The wall thickness of is preferably 3 mm or less. As its material,
The inner layer (10) and the outer layer (11) can be made of rubber such as silicone rubber, natural rubber, polyurethane, soft vinyl chloride resin or soft synthetic resin, and are made by dipping molding, slush molding, extrusion molding, etc. 0.1-
It has a tube shape of 1.5 mm.

As the spiral body (12), stainless steel,
It is preferable to use a metal such as a nickel titanium alloy, preferably spring steel. Besides, a synthetic resin wire having elasticity and flexibility can also be used, and for example, a synthetic resin wire such as a polyamide resin or a polyester resin is used. The wire diameter is 0.1 to 1.5 mm, preferably 0.4 to 0.7 mm, and the spiral pitch is suitably 0.3 to 3 mm.

The encapsulating material (13) is composed of the inner layer (10),
The outer layer (11) and the spiral body (12) are adhered and fixed to be integrated, and these three parts can be easily combined by injecting a liquid resin into a necessary portion using a thin nozzle such as a combined injection needle. Can be manufactured. At this time, a part of the inner layer (10) located in the vicinity of the base end portion (5) is not adhered and fixed to the encapsulating material (13), that is, is peeled off, so that the swellable inner elastic bag (14) is formed. ) Is formed.
As the liquid resin used, for example, a synthetic resin having flexibility after curing such as silicone rubber or polyurethane resin is suitable. In addition, the inner layer (10), the outer layer (11) and the encapsulant (13) may be integrally formed, for example, by inserting the spiral body (12) into a liquid silicone rubber injection molding die instead of being an independent part. It is possible and, of course, within the scope of the invention.

As mentioned above, one end of the branch pipe (7) is
A gap between the encapsulating material (13) and the inner elastic bag (14), that is, an opening in the inner elastic bag (14) is open for gas-liquid flow, and the other end passes through the base end (5) and then It branches from the end face. As the material thereof, a material having appropriate flexibility and hardness such as soft vinyl chloride resin, urethane resin, silicone rubber, and natural rubber is preferable, and the extruded inner diameter is 0.3 to 2 mm and the wall thickness is 0.3. ~ 1.5mm, length 5 ~ 20cm
A degree of tubing is used.

At the rear end of the branch pipe (7), as shown in FIG. 1 (c), a pilot balloon (8) and a check valve (9) for inflating and deflating the inner elastic bag (14). ) Is connected to the expansion device. The pilot balloon (8) and the check valve (9) may use the components generally used in commercially available medical balloon products. The check valve (9) can be easily attached and detached to and from the injection cylinder, and the inner elastic bag (14) can be inflated or contracted by injecting or discharging gas or liquid. The pilot balloon (8) is for monitoring the expansion state of the inner elastic bag (14).
Even if it is replaced with a commercially available two-way or three-way cock, the function is satisfactory.

Next, the function of the inner elastic bag (14) will be described. When the trocar according to the present invention is pierced into the body surface and inserted into the body wall and the inner needle is removed, as shown in FIG. The positive pressure gas sent to inflate leaks. Therefore, when gas or liquid is injected from the branch pipe (7) to inflate the inner elastic bag (14), the lumen of the outer tube is closed as shown in FIG. 2 (b),
It is possible to prevent leakage of positive pressure gas. In addition, FIG.
As shown in Fig. 1, various medical devices (1
Even when 9) is inserted, by expanding the inner elastic bag (14), the gap between the outer tube and the handle of the medical device is filled, and airtight sealing can be achieved.

Since the needle tip (1) has a sharp blade tip at the tip as described above, when the needle body (2) is inserted into the inner cavity of the outer tube body (4) and set, It is preferable for safety that the needle tip (1) is housed and hidden in the tip (6) of the main body (4) as shown in 3 (b).
Then, it is desirable that the tip tip (6) retracts spontaneously during puncture so that the needle tip (1) is completely exposed. As an example, a structure as shown in FIG. It is effective to provide.

That is, a part of the space between the inner layer (10) and the outer layer (11) forming the main body (4) of the outer tube, near the tip, is filled with the encapsulating material (13). Provided,
The expandable part (15) is formed by making the spiral body (12) contained in the tube wall expandable and contractable in the length direction. At the time of use, the surgeon grasps the handle (3) or the proximal end portion (5) and pierces the body wall, and when the needle tip (1) enters the biological tissue, the puncture resistance is applied to the tip (6). ) Receive the elastic part (1
The spiral body (12) contained in 5) is compressed, and the spiral body (12) of FIG.
As shown in (3), the tip (6) is retracted to expose the needle tip (1), and the puncture proceeds smoothly. Then, the needle tip (1)
When the tip chip (6) and the tip tip (6) have finished entering the body cavity, the puncture resistance decreases, and the elastic recovery force of the spiral body (12) restores the length of the expandable portion (15) to push out the tip tip (6). , The state where the needle tip (1) is stored, and the state of FIG.

As shown in FIG. 3 (c), when the expandable part (15) is compressed and deformed, the inner and outer layers (10, 11) forming the tube wall of the expandable part are folded in a bellows shape to form the spiral body (1).
Enter the gap of 2). The total length of the mantle tube is 1
Although it is determined in consideration of the shrinkage allowance of 5) and the blade tip length of the needle tip (1), it is generally preferable that the shrinkage allowance is about the blade tip length of the needle tip (1) + 5 mm. The outer diameter of the needle tip (1) is
The inner diameter of the tip (6) is set to be almost the same as that of the needle body (2) so that the living tissue does not enter the gap inside the tip (6) during the puncture to provide extra puncture resistance. The outer diameter may be smaller than the inner diameter of the outer tube, and has a small diameter in order to reduce slip resistance between the needle and the outer tube, or to absorb the bellows deformed portion of the tube wall layer of the expandable portion (15). The invention is also included in the scope of the present invention.

In order to prevent the outer tube from falling off the body wall or the tip of the outer tube from escaping from the body cavity when the outer tube is placed on the body wall by puncturing the trocar according to the present invention, As shown in FIG. 4, the outer elastic bag (16, 17) is provided on the outer surface of the outer tube main body (4) near the distal end and / or the proximal end (5). The method is
Similar to the inner elastic bag (14) shown in FIG. 2, the outer elastic bag (11) and the encapsulant (13) forming the tube wall of the corresponding portion are not adhered and fixed, but are peeled off to leave the outer elastic bag. (16, 17) is formed. Further, the elastic portion (15) may be applied to this. Then, the gap between the encapsulant (13) and the outer elastic bag (16, 17), that is, the outer elastic bag (16,
One end of the branch pipe (7, 18) that serves as a gas-liquid flow passage is opened in 17), and the other end passes through the pipe wall of the mantle tube and the base end portion (5) and comes out from the rear end face of the branch pipe. I am divided.

The branch pipe for the outer elastic bag (16) on the side of the proximal end (5) may be shared with the branch pipe (7) for the inner elastic bag (14), or provided separately. But it doesn't matter. When shared, it can be easily manufactured by gas-liquid communication with the inner elastic bag (16) without encapsulating the necessary part of the spiral body (12) with the encapsulating material (13). On the other hand, a branch pipe (18) is provided for the outer elastic bag (17) on the distal end side. At the rear end of each branch pipe, as shown in FIG. 4, an inner elastic bag (14) composed of a pilot balloon (8 ') and a check valve (9') for expanding and contracting the outer elastic bag is provided. )
Connect a similar expansion device used for.

After the trocar is punctured from the body surface and inserted to the target position, gas or liquid is injected by the inflator described above, and an outer elastic bag () located outside the body wall and / or inside the body cavity ( The outer tube can be fixed to the body wall by expanding (16, 17). Further, the dimension of the outer elastic bag (16, 17) in the length direction of the outer tube is not particularly limited,
If a wide range is set in advance, the part of the outer elastic bag located inside the body wall cannot expand when it is inserted into the body wall and left in place, so only the front and rear parts that sandwich the body wall will expand. It is preferable that the mantle tube can be placed and fixed at any position.

[0035]

The trocar according to the present invention comprises the body part (4) of the outer tube.
It is made of a flexible material with a spiral body (12) embedded in it and reinforced, and it is bendable due to its appropriate flexibility and elasticity, and it has sufficient hardness for puncturing and is indwelling on the body wall. The requirement of the trocar for reliable retention of the lumen of the trocar can be satisfied.

Further, the inner layer (10) and the outer layer (11) forming the tube wall of the main body (4) are partially separated from the encapsulating material (13) to form a gap, and a gas or liquid is injected from the expansion device. It is equipped with an elastic bag that can be expanded.
The swelling of these inner elastic bags (14) can surely block the leakage of positive pressure gas from the body cavity, and the swollen elastic bags have appropriate flexibility and elasticity. Widely conforming to the shape of (19), it is possible to perform an airtight seal without hindering the operation.

Furthermore, by utilizing the outer elastic bags (16, 17), the tissue damage at the body wall puncture can be suppressed to a necessary minimum and airtight fixation can be surely performed, and the peeling space of the outer layer (11). Since the position can be freely set, it is possible to provide a trocar that can be pressed and fixed at any portion of the puncture opening in the thickness direction of the body wall. Further, since these elastic bags are formed by using the outer tube constituting member, unnecessary inner and outer swelling does not occur.

Furthermore, the spiral body (1) for reinforcing the main body (4)
Since the elastic part (15) is provided by utilizing the impact resilience of (2), it is possible to simply provide a safety mechanism that prevents organ damage due to the needle tip (1) immediately after penetrating the body wall.

[0039]

As described above, by using the trocar according to the present invention, medical instruments such as forceps having various curved and bent shapes suitable for the operative field can be obtained without being dimensionally restricted by the inner diameter of the mantle tube. Since it can be inserted, it can be used for surgery and the range of instruments used can be expanded, and the safety and invasiveness of surgery can be reduced. Further, it is possible to provide desired functions as a trocar with a relatively simple mechanism such as leakage of positive pressure gas, airtight fixing of the body wall, and prevention of organ damage immediately after penetrating the body wall. It is useful as a trocar used for surgical treatment.

[Brief description of drawings]

FIG. 1 is a diagram showing the entire trocar needle according to an embodiment of the present invention, in which (a) is a schematic view of an inner needle, (b) is a cutaway sectional view of an outer tube, and (c) is an outer tube. It is a general-view figure of the state which inserted the inner needle.

FIG. 2 is a cross-sectional view in the vicinity of a base end portion of an outer tube.

FIG. 3 is a cross-sectional view of a telescopic portion of an outer tube according to an embodiment of the present invention and a schematic view showing an operating state.

FIG. 4 is a schematic view of an outer elastic bag provided on the outer surface of an outer tube according to an embodiment of the present invention.

[Explanation of symbols]

 1 Needle tip 2 Needle main body 3 Handle 4 Main body 5 Base end 6 Tip tip 7,18 Branch pipe 8,8 'Pilot balloon 9,9' Check valve 10 Inner layer 11 Outer layer 12 Helical body 13 Encapsulating material 14 Inner elastic bag 15 Elastic part 16,17 Outer elastic bag 19 Medical device

Claims (3)

[Claims] 1. An outer tube that is inserted into and fixed to a body wall, and an inner needle that is formed so as to be insertable into and removable from the inner cavity of the outer tube and that has a puncture portion at the tip and a grip portion at the rear end. A trocar,
The mantle tube is composed of a flexible main body which is bendable and is reinforced by a spiral body, and a brim-shaped base end portion, and an inflatable inner elastic bag is formed on the inner surface near the base end portion of the main body portion. A trocar that is provided with a branch pipe A in gas-liquid communication with the inner elastic bag inside the pipe wall near the base end, and the branch pipe A is branched at the rear surface of the base end. . 2. A trocar according to claim 1, further comprising an expanding / contracting portion formed near the distal end of the outer tube main body so as to extend / contract in a longitudinal direction a spiral body incorporated in the tube wall. Tube needle. 3. An outer elastic bag capable of bulging is provided on the outer surface of the outer tube body near the tip and / or the base end, and the outer elastic bag and the gas-liquid are provided inside the tube wall of the body. 3. The trocar according to claim 1 or 2, wherein a branched branch pipe B is provided, and the branch pipe B is branched at the rear surface of the base end portion.