JPS627849B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a trocar for puncturing the abdominal wall of a rigid endoscope or the like prior to insertion into the abdominal cavity.

Generally, when a rigid endoscope or the like is inserted percutaneously into the abdominal cavity, pretreatment such as anesthesia is first performed, and then a pneumoperitoneum needle is inserted to perform pneumoperitoneum. A trocar is then punctured into the insufflated abdominal wall, and a rigid endoscope or the like is inserted into the abdominal cavity using the trocar as a guide.

However, conventional trocars consist of an outer tube and an inner needle that is removably inserted into the outer tube, and the inner needle has a tip with a sharp cutting edge that protrudes from the tip of the outer tube. When puncturing the abdominal wall with this trocar, a small incision is made in a part of the abdominal wall using a scalpel, and the tip of the trocar is inserted by strongly pushing into this small incision.

However, this method requires a high degree of skill to perform the puncturing operation, since the entire trocar is manually punched in to insert the trocar. Furthermore, since the sharp tip of the inner needle protrudes from the tip of the trocar's outer tube, there was a risk that if the needle was pushed in too far, it would reach internal organs and damage those organs.

On the other hand, conventionally, it has been considered that an inner needle protruding from the tip of an outer tube has a spiral threaded portion formed on the circumferential surface of the tip thereof so that the inner needle can be inserted by screwing.

However, this method also requires the same tapping and pushing operation as the above-mentioned trocar when inserting the mantle, and has the same drawbacks.

The present invention has been made focusing on the above circumstances,
The purpose is to provide a trocar that can be easily and safely inserted into the mantle without having to hit the tip of the trocar against the body wall.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a trocar, which is composed of an inner needle 1 and an outer cannula 2. As shown in FIG. The mantle tube 2 has a grip main body 4 provided at the proximal end of the insertion tube portion 3 thereof. The inner needle 1 is detachably inserted into the outer tube 2 from the side of the grip body 4, and its distal end 5 is attached so as to protrude from the distal end of the outer tube 2.
Further, the tip 5 of the inner needle 1 is formed into a conical shape,
A spiral threaded portion 6 is formed on the circumferential surface 5a of the distal end portion.

Furthermore, the distal end 7 of the outer tube 2 is formed as a conical circumferential surface that is continuous with the distal circumferential surface 5a of the inner needle 1, and a spiral threaded portion 8 is formed on the distal circumferential surface 7a. ing. The thread ridge direction, pitch, and number of threads of each of the threaded portions 6 and 8 are the same. A notch 9 is formed at the proximal end of the outer tube 2, and a locking pin 10 protruding toward the inner needle 1 is engaged with the notch 9. Then, by inserting the inner needle 1 into the outer tube 2 and fitting the locking pin 10 into the notch 9, the inner needle 1 and the outer tube 2 cannot rotate relative to each other. In other words, the notch 9 and the locking pin 10 constitute an engaging means for preventing relative rotation between the two.

Further, when the locking pin 10 is fitted into the notch 9 and locked, the ridge lines of the threads of the threaded portions 6 and 8 coincide as shown in FIG. 2. In other words, the positions are arranged so that the phases are continuous.

Next, when using the trocar, the patient is first anesthetized as a pretreatment and then insufflated with a pneumoperitoneum needle (not shown) to isolate the abdominal wall and organs. Next, make a small incision with a scalpel at the point where the trocar is to be punctured, and insert the tip 5 of the inner needle 1 into the outer mantle tube 2 into this incision.
The trocar is moved forward by gripping the grip main body 4 and rotating the entire trocar and screwing in the threaded portions 6 and 8 while applying the trocar. The inner needle 1 and the outer tube 2 are positioned and fixed by fitting and engaging a locking pin 10 into the notch 9, and can be rotated together. At the initial stage of this puncture operation, only the threaded portion 6 of the inner needle 1 engages with the abdominal wall, especially the peritoneum, which is the innermost layer.
As the needle moves further forward, the distal end 5 of the inner needle 1 penetrates the peritoneum, and then the threaded portion 8 on the side of the mantle tube 2 becomes engaged with the peritoneum. In this state, the threaded portion 6 on the inner needle 1 side does not engage with any part of the abdominal wall and protrudes into the abdominal cavity. In other words, the threaded portion 6 on the inner needle 1 side is released from the abdominal wall. Therefore, when the surgeon pulls the inner needle 1 toward the proximal side, the outer canal 2
It can be easily pulled out. This allows the operator to know that the internal needle 1 has finished penetrating the peritoneum.

Further, even if the inner needle 1 is pulled out from the outer tube 2 at this time, the threaded portion 6 of the inner needle 1 does not act when the outer tube 2 is advanced any further, so there is no problem even if the inner needle 1 is pulled out. Rather, since the sharp tip 5 of the inner needle 1 is removed without protruding, it is possible to prevent injury to the internal organs, which is extremely desirable for safety.

After pulling out the inner needle 1, rotate only the outer tube 2 and screw it into the abdominal wall using its threaded portion 8.
The puncturing operation of the trocar is completed by penetrating the abdominal wall. In this case, since a threaded portion 8 is formed at the distal end portion 7 of the mantle tube 2, the mantle tube 2 can be screwed into it. Furthermore, since this threaded portion 8 engages with the abdominal wall, the outer tube 2 will not come off even if the inner needle 1 is pulled out. In other words, the inner needle 1 can be safely pulled out.

Further, in the above embodiment, the locking pin 10 is provided in the notch 9.
By engaging the inner needle 1 and the cannula 2 and positioning them, the ridge lines of the threads of the threaded parts 6 and 8 are aligned, so the trocar screwing operation can be done without pulling the trocar until the cannula 2 penetrates the peritoneum. It can be done smoothly without getting stuck.

As explained above, in the present invention, threaded portions are formed on the peripheral surfaces of the distal ends of the inner needle and the outer tube of the trocar, so that puncturing can be performed by screwing not only the inner needle of the trocar but also the outer tube. In other words, it is possible to insert the trocar up to the mantle tube without having to forcefully push (beat) the trocar. Moreover, after the tip of the inner needle has penetrated, it can be pulled out, and it can thus be easily recognized that the tip of the inner needle has penetrated, for example, the peritoneum of the abdominal wall. Furthermore, since the threaded portion at the distal end of the outer tube is screwed into engagement with the abdominal wall, the inner needle can be pulled out with confidence. Furthermore, after the tip of the inner needle has penetrated, all you have to do is pull it out, so the sharp tip of the inner needle will not protrude from the tip of the outer tube, so you can safely screw in the outer tube. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a side view of a trocar showing an embodiment of the present invention, and FIG. 2 is a side sectional view of the distal end of the trocar. 1... Inner needle, 2... Outer tube, 5... Tip, 5
a...Tip circumference, 6...Threaded part, 7...Tip, 7a...Tip circumference, 8...Threaded part, 9...
Notch, 10...locking pin.

Claims (1)

[Scope of Claims] 1. In a trocar consisting of an outer tube and an inner needle that is detachably inserted into the outer tube, the peripheral surface of the tip of the outer tube and the circumference of the tip of the inner needle protruding from the tip of the outer tube. A trocar characterized by having a spiral threaded portion formed on each side so that it can be screwed into the body wall. 2. The trocar according to claim 1, further comprising an engaging means for engaging the outer tube and the inner needle and preventing relative rotation between the two. 3. Claim 2, wherein the engaging means is configured to engage the outer tube and the inner needle at a position where the respective ridge lines of the threaded portion of the outer tube and the threaded portion of the inner needle are continuous. Trocar as described in Section.