WO2014118752A2

WO2014118752A2 - Laparoscopic trocar

Info

Publication number: WO2014118752A2
Application number: PCT/IB2014/058717
Authority: WO
Inventors: Antonino Cuzzucoli
Original assignee: Medi-Line S.R.L.
Priority date: 2013-02-01
Filing date: 2014-01-31
Publication date: 2014-08-07
Also published as: WO2014118752A3; ITRC20130001A1

Abstract

A laparoscopic Trocar (1) comprising a cannula (2) and an obturator (3) adapted to be housed inside the cannula (2) during crossing of the abdominal wall. The obturator (3) is provided with a tip (11) comprising, in turn, a frustoconical dilation portion (8a), a blade (10a) which protrudes from the frustoconical dilation portion and a retractable protection portion (9a), arranged around the blade (10a) and adapted to run inside the frustoconical dilation portion (8a) to move between a rest position, in which the blade (10a) is covered, and an active position, in which the blade (10a) is uncovered. The frustoconical dilation portion (8a) comprises a closed lateral wall (8b) tapering towards a free end thereof defining a circular aperture (8c) from which the blade (10a) and the protection portion (9a) protrude when in the rest position.

Description

"LAPAROSCOPIC TROCAR

TECHNICAL FIELD

The present invention concerns a laparoscopic surgery entry device, commonly called "Trocar".

Trocar devices are designed to provide communication between the inside and outside of the abdomen. The type of Trocar used in surgery can vary according to the type of operation.

BACKGROUND ART

Generally, Trocars are composed of a cannula and an obturator which in use is housed inside the cannula. The obturator has a distal portion, called tip, which protrudes from the cannula and has the function of making an opening in the abdominal wall, passing through the peritoneum. Once, the intra-abdominal area has been reached, the obturator is slipped out of the cannula which remains, constituting an entry channel to the inside of the intra-abdominal area for a camera and/or for surgical instruments.

As will be evident to a person skilled in the art, one of the problems with the use of Trocars concerns safety during their insertion into the abdomen. In this regard, the type of tip used is all - important .

Currently, laparoscopic Trocars exist with cutting tip and with dilating cone-shaped tip. The laparoscopic Trocars with cutting tip represent the type of Trocar most commonly used. These Trocars comprise a blade with a very broad cutting surface, proportional to the diameter of the cannula, a cone-shaped dilating tip, the largest dimension of which is the size of the maximum width of the blade and slightly smaller than the diameter of the cannula .

For these Trocars, therefore, the larger the diameter of the cannula, the larger the surface of the blade exposed during entry. In this way, the cut made by the blade is of dimensions such as to permit simple entry of the cannula without a particular penetration effort.

In particular, the Trocars with blade comprise a retractable tip, which is forced by elastic means to assume a position in which it covers the blade. During insertion of the Trocar, the retractable tip is forced by the abdominal wall to run inside the cannula, thus exposing the blade. Once the retractable tip has passed through the peritoneum and reached the abdominal cavity, it is no longer withheld by the abdominal wall and, due to the action of the elastic means, returns to its rest position until it covers the blade, thus ensuring the safety thereof. In this type of trocar, due to the considerable width of the blade, both the dilating tip and the retractable tip are provided with at least two opposite longitudinal apertures adapted to house the lateral edges of the blade .

This type of Trocar suffers from the drawbacks resulting from the presence of a blade with dimensions comparable to those of the diameter of the cannula. In fact, in this case the dimensions of the blade are such as to cause cutting of the vessels with consequent bleeding. For a more complete evaluation of the gravity of the problem, it should be remembered that during surgery, the walls of the cannula may block the bleeding of the cut vessels. In this way, the surgeon may not notice the damage caused and, once the patient has come out of the operating theatre at the end of the operation, he/she may suffer a haemorrhage. Laparoscopic Trocars with dilating cone-shaped tip without blade are less traumatic than those with blade, but have a lower penetration coefficient and, therefore, require greater force during insertion. With this type of Trocar, the tissue is simply moved rather than being cut, thus preserving the fascia. In this case the -advantage is not only minimisation of the risk of cutting the vessels when passing through the abdominal wall, but also the extent of fascial defects is reduced, diminshing the risk of post operative hernia. However, this entry system has the drawback of being less penetrating and, consequently, requires a greater pushing force by the operator, resulting in reduced control of the device once the space of the abdominal cavity has been reached. The consequence of this drawback is necessarily a high risk of lesions to the internal organs since the conical tips have no system for protection of the point.

The need was therefore felt for a laparoscopic Trocar comprising a tip with technical characteristics such as to solve the drawbacks of the tips of the -known art described above .

DISCLOSURE OF INVENTION

The subject of the present invention is a laparoscopic Trocar, the essential characteristics of which are described in claim 1, and the preferred and/or auxiliary characteristics of which are described in claims 2-5.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment example is described below for purely illustrative non- limiting purposes with the help of the accompanying figures, in which:

figure 1 is a lateral view of the laparoscopic Trocar subject of the present invention according to a preferred embodiment; figure 2 is an exploded view of the laparoscopic Trocar of figure 1;

figure 3 is a lateral view of a portion of the laparoscopic Trocar of figure 1 in a first operative configuration thereof; figure 4 is a lateral view of the portion of figure 3 in a second operative configuration thereof.

BEST MODE FOR CARRYING OUT THE INVENTIO

In figures 1 and 2, a laparoscopic Trocar according to the present invention is indicated as a whole by the number 1.

As illustrated in figure 2, the laparoscopic Trocar 1 substantially comprises a cannula 2 and an obturator 3 in use housed inside the cannula 2. The cannula 2 is composed of its own head portion 4 adapted to contain a group of sliding seals known and not described in detail, a duct 5 with open ends and extending from the head portion 4 and a tap 6 also extending from the head portion 4, - the function of which is known.

The obturator 3 comprises its own head portion 7 which, as illustrated in figure 1, when the obturator 3 is arranged inside the cannula 2, slots into the head portion 4 of the cannula 2 to provide one single handgrip la.

The obturator 3 furthermore comprises an outer tube 8 with open end extending at the bottom from the head portion 7 , an inner tube 9 housed with freedom of movement (as will be described below) inside the outer tube 8 and a sharp point 10 (visible only in figure 4) housed in the inner tube 9 and fixed with respect to the outer tube 8. In the attached figures, only end portions 9a and 10a of the inner tube 9 and sharp point 10 respectively can be seen. In particular, the end portions 9a and 10a protrude from an end portion 8a of the outer tube 8. The end 10a (visible only in figure 4) of the sharp point 10 is made of carbon fibre and constitutes the blade of the obturator 3. Below, therefore, "the blade" will be indicated by the reference number 10a. As illustrated in figures 3 and 4, the assembly formed by the end portions 8a, 9a and 10a constitutes the tip 11 of the laparoscopic Trocar of the present invention.

The end portion 8a of the outer tube _.8 forms a "dilation portion" (below indicated by reference number 8a) of the tip 11 and has a frustoconical shape consisting of a closed lateral wall 8b tapering towards a free end thereof where it defines a circular aperture 8c. The lateral wall 8b comprises two diametrically opposite longitudinal tabs 12 which function as separators. Again on the lateral wall 8b a plurality of longitudinal grooves 13 are obtained having an anti- friction function.

The end portion 9a of the inner tube 9 forms a "protection portion" (indicated below by the reference number 9a) of the tip 11 and has a substantially cylindrical shape extending from the circular aperture 8c defined by the lateral wall 8b of the end portion 8a of the outer tube 8. As illustrated in figure 4, since the inner tube 9 is mobile inside the outer tube 8, overcoming the action of elastic means known and not described, the protection portion 9a is retractable inside the dilation portion 8a to leave the blade 10a uncovered.

The movement of the inner tube 9 and, therefore, of the protection portion 9a, is possible only after release of a safety device by operation of the button 14 (setting it to a retracted position) arranged on the head 7 of the obturator 3.

In particular, the point 10a of the tip 11 has a flat shape and two lateral edges which are housed by sliding inside two longitudinal apertures obtained in the protection portion 9a.

From what is described above, the tip of the laparoscopic Trocar comprises a dilation portio 8a having at any point a diameter always greater than the maximum surface of the blade 10a, the dimensions of which are only comparable to those of the circular aperture 8c. Due to the above dimensional characteristic, the dilation portion 8a of the Trocar of the present invention differs from the dilation portions of the Trocars of the known art in that it is composed of a closed wall. The Trocars of the known art, on the other hand, having a blade with a surface of dimensions comparable to the maximum diameter of the dilation portion, must necessarily have a dilation portion with two longitudinal apertures to house the lateral edges of the blade. ,

In the same way, the protection portion 9a has a diameter comparable to that of the circular aperture 8c and the blade 10a. The' substantial coincidence between the diameter of the protection portion 9a and the blade 10a means that in the same protection portion 9a two longitudinal apertures must be obtained to house the lateral edges of the blade 10a housed in it. In use, once the obturator 3 has been coupled to the cannula 2 and the button 14 has been operated, the Trocar 1 is moved forward to the established entry point and an appropriate pressure is exerted. The pressure exerted on the tissue causes retraction of the protection portion 9a and simultaneous exposure of the blade 10a, which has the job of making a small opening which is then dilated by the dilation portion 8a. The dilation is facilitated by the presence of the longitudinal tabs 12 and by the grooves 13. Once the abdominal cavity has been reached, the protection portion 9a is no longer withheld by the abdominal wall and returns to the position in which it covers the blade 10a. Since the protection portion 9a, like the blade 10a, has small dimensions, automatic activation of the protection is immediate and. thus avoids prolonged exposure of the blade 10a in the abdominal cavity. Furthermore, the fact that the blade 10a is made of carbon fibre gives it a lower risk margin than the blades of the Trocars of the known art .

Once the protection portion 9a returns to the position in which it covers the blade 10a, the button 14 returns to an advanced position and the mobility of the same protection portion 9a is blocked.

Since the diameter of the duct 5 of the cannula 2 varies according to the type of instrument to be used, the diameter of the dilation portion 8a of the tip 11 will also vary according to the dimension of the duct 5, while the dimensions of the protection portion 9a and the blade 10a will always remain the same. This demonstrates that the incidence of the cut is always the same, regardless of the dimensions of the duct 5 and, therefore, of the gauge of the trocar to be used. The Trocar subject of the present invention has the great advantage of comprising a blade and a protection portion of considerably smaller dimensions than those of the cannula, with the consequence of minimising the risk of cutting the vessels, and therefore bleeding, and obtaining immediate automatic activation of the protection.

To conclude, the laparoscopic Trocar according to the present invention comprises a tip which, although provided with blade, does not have the drawbacks of the Trocars of the known art with obvious advantages in terms of safety; at the same time, it maintains part of the components unchanged regardless of the gauge of the trocar with obvious advantages in terms of productivity and use.

Claims

1. A laparoscopic Trocar (1) comprising a cannula (2) and an obturator (3) adapted to be housed inside the cannula (2) during crossing of the abdominal wall; said obturator (3) is provided with a tip (11) comprising a frustoconical dilation portion (8a) , a blade (10a) which protrudes from said frustoconical dilation portion and a retractable protection portion (9a), arranged around the blade (10a) and adapted to run inside the frustoconical dilation portion (8a) to move between a rest position, in which the blade (10a) is covered, and an active position, in which the blade (10a) is uncovered; said Trocar being characterised in that said frustoconical dilation portion (8a) comprises a closed lateral wall (8b) tapering towards a free end thereof defining a circular aperture (8c) from which the blade (10a) and said protection portion (9a) protrude when in the rest position.

2. Laparoscopic Trocar according to claim 1, characterised in that. said blade (10a) is made of carbon fibre.

3. Laparoscopic Trocar according to claim 1 or 2, characterised in that said blade (10a) has a flat shape.

4. Laparoscopic Trocar according to claim 3, characterised in that said protection portion (9a) has a substantially cylindrical shape having two opposite longitudinal apertures adapted to house in a sliding manner the two lateral edges of said blade (10a) with flat shape.

5. Laparoscopic Trocar according to one of the preceding claims, characterised in that said lateral wall (8b) of the frustoconical dilation portion (8a) comprises a pair of longitudinal tabs (12) arranged diametrically opposite to each other and a plurality of longitudinal grooves (13) .