FR2727849A1 - Trocar for use in human or veterinary coeloscopy - Google Patents

Abstract

The trocar consists of a hollow tube which allows an instrument to be inserted through it, and a system for introducing a gas through a supple duct connected to the proximal end of the tube. The end of the tube has a stopper to prevent a back-flow of gas, made in the form of a cylindrical body (25) and at least two elastically deformable lips (31,32). The body of the stopper ends in two straight transverse edges or a membrane (36) with an aperture (37) which is slightly smaller than the instrument to be inserted through it. The stopper is made e.g. from silicone, and its outer surface has annular sealing ribs.

Description

 TROCART FOR ENYINR 0U VETBRIXAIRB COELIOSCOPY.

 The present invention relates to a trocar for human or veterinary laparoscopy.

Such trocars are known in the prior art, and reference may be made to French patents
FR2697150 or FR2689384 for the general characteristics.

 However, the prior art trocar has several drawbacks with regard to cleaning after use.

 The state-of-the-art trocars are of relatively complex mechanical construction, which makes removal difficult and even more so the cleaning of each of the parts making up said valve. In addition, it is frequent that certain parts, such as the spring or the ball of the valve are lost.

 Patent FR2689384 proposes a sealing element, the distal part of which has a housing normally closed by a plastic membrane.

This solution is not completely satisfactory because it requires additional disassembly during cleaning. However, the multiplication of the number of parts is always a source of errors and risks of forgetting during sterilization operations.

 The object of the present invention is to provide an improved trocar avoiding these drawbacks.

 To this end, the trocar according to the invention comprises a hollow tubular element suitable for allowing the passage of a tool and provided with means for insufflating a gas coming from a flexible duct connected to the proximal part of the hollow tubular element, the trocar comprising a means for preventing the return of the gas in the channel formed in the tubular element, characterized in that said sealing means is constituted by a removable plug, capable of being sealed in a cavity provided at the proximal end of the tubular element, and comprising at least two elastically deformable lips.

 Advantageously, the tubular element has at its proximal end a cylindrical cavity and in that the plug is formed by a cylindrical body whose outer surface is adapted to tightly match the inner surface of said cavity.

 According to a variant, the plug has on its outer surface at least one annular protuberance to reinforce the seal.

 Preferably, the cylindrical body is provided with two lips extending in the distal direction and ending with substantially rectilinear transverse edges.

 According to a variant, the stopper also has a substantially transverse sealing membrane, pierced by an orifice of a section slightly smaller than the section of the instrument passing through the trocar.

 According to an advantageous variant, the trocar according to the invention further comprises at least one adapter constituted by a tubular element having an outside diameter substantially equal to the inside diameter of the stopper and an inside diameter suitable for the passage of a laparoscopy instrument.

The invention will be better understood on reading the following description, referring to the accompanying drawings where
- Figure 1 shows a cross-sectional view of the trocar with the valve in the open position
- Figure 2 shows an enlarged view of the plug
- Figure 3 shows a view along a section plane AA 'of the plug.

 We will first describe the general characteristics of the trocar.

 The trocar according to the invention comprises a tubular element constituted by a piece of stainless steel, and Teflon or polyacetal, having a proximal part (1), an intermediate part (2) and a distal part (3), of decreasing sections. The proximal part opens at the back to allow the insertion of a surgical instrument. The distal part (3) has on its outer surface a thread or annular protrusions to facilitate the insertion of the trocar into the peritoneum. The end of the distal part (3) is constituted by a smooth cylindrical zone (4), the last annular protuberance (5) or the distal end of the screw thread being disposed at a determined distance from the end of the distal element to provide the surgeon with an indication of the depth of penetration of his tool.

 The intermediate zone (2) has an annular groove (6). At this annular groove (6), the wall is pierced by a plurality of orifices (7, 8), for example 6 in number distributed regularly spaced. On either side of this annular groove (6) are O-rings (9, 10), engaged in annular grooves. A third O-ring (11) is arranged in an annular groove provided behind (towards the proximal end) of the two previous O-rings (9, 10).

 Around the intermediate zone (2) is a movable sleeve (11). This movable sleeve (11) consists of a cylindrical element coaxial with the intermediate zone (2), and of an internal section adapted to allow movement in translation relative to the tubular element of the trocar and to ensure the sealing of the space between the inner wall of the sleeve (12) and two consecutive seals (9, 10) or (10, 11), at the usual pressures during gas blowing.

 The sleeve (12) has a conduit (13) opening radially and making it possible to connect the gas inlet conduit. This conduit communicates with the interior of the sleeve.

 The sleeve is movable between two extreme positions. In the open position, as shown in Figure 1, it abuts against a ring (14) screwed onto the end of the intermediate zone (2). In this position, the device has an annular chamber delimited by the inner wall of the sleeve (12), by the two O-rings (9, 10) arranged on either side of the annular groove (6), and by the wall outside of the intermediate zone (2) comprising said annular groove (6). The annular chamber thus formed communicates on the one hand with the gas inlet duct via the connection duct (13), and on the other hand with the internal channel (15) of the tubular element, by the 'through the 6 passages (7, 8).

 In this position, it is possible to inject gas. The proximal area (1) is closed by a plastic plug (16) which fits tightly in the cavity provided for this purpose in the proximal part (1). This plug (16) has two lips (17, 18) or any other equivalent means for sealing the plug (16). These lips (17, 18) are directed in a distal direction so that the pressure of the gas pushes the lips (17, 18) against each other and improves the sealing of the stopper.

When an instrument is inserted into the trocar, it pushes the lips (17, 18) which move apart to let said instrument pass and conform to the external surface of said instrument. Sealing in the presence of an instrument is improved by the presence of an annular sealing collar (19) which is pressed against the body of the instrument.

 When the sleeve is in the closed position, it is moved in the proximal direction and abuts against a shoulder (20). The inner channel (1) is then isolated from the gas inlet pipe, by the median O-ring (10). The connection conduit (13) opens into a space sealed in a sealed manner by the inner wall of the sleeve (12), the outer wall of the intermediate zone (2), by the median O-ring (10) and by the proximal O-ring. (11).

 The device according to the invention is essentially composed of three parts: the tubular element machined or molded in a single part, the ring (14) and the sleeve (12). To these three main parts are added the three O-rings (9, 10, 11). These parts are easy to disassemble and reassemble.

Cleaning and sterilization is easy. As a result, the device according to the invention not only improves the ergonomics of the trocar, but responds to the constant concern, in the operating room, of making sterilization of the instruments as simple and effective as possible.

 FIGS. 2 and 3 represent enlarged views of the plug, according to two perpendicular cutting planes and according to an alternative embodiment different from that described with reference to FIG. 1.

 The stopper has a cylindrical silicone body (25) having on its outer surface rings (26, 27, 28) having a face (30) directed towards the conical distal end forming a slope of the order of 45 degrees relative to in the transverse plane (29) and a proximal face substantially parallel to the transverse plane (29) of the plug. At the proximal end of the stopper, the cylindrical body (25) is provided with a disc extension extending outward in the transverse plane, and coming to bear on the end of the tubular element of the trocar to contribute to the sealing of the device.

 Inside the body (25), the plug has two lips (31, 32) symmetrical with respect to a median plane (33) perpendicular to the transverse plane (25). The two lips (31, 32) are connected to the inner wall of the cylindrical body (25) along two semi-circular lines. The end (34, 35) of the lips has straight edges extending diametrically over the width of the stopper. The two edges (34, 35) are pressed against each other at rest, in a substantially rectangular area in the median plane (33), and thus ensure the sealing of the plug.

When the pressure on the distal side is greater than the pressure on the proximal side, the angle formed by the two lips (31, 32) results in a force comprising a radial component acting perpendicularly to the median plane and tending to reinforce the pressure the ends of the lips against each other.

 The distal end of the stopper is partially closed by a cover (36) in a transverse plane, pierced by an orifice (37) whose section is slightly smaller than the outside section of the laparoscopy instrument so as to allow a tight passage , but not prohibiting the degrees of freedom in longitudinal translation and in rotation relative to the longitudinal axis.

Claims (7)

RI'rIMDICATIOlS.  1 - Trocar for human or veterinary laparoscopy, of the type comprising a hollow tubular element suitable for allowing the passage of a tool and provided with a means for insufflation of a gas coming from a flexible duct connected to the part proximal of the hollow tubular element, the trocar comprising a means for preventing the return of gas in the channel formed in the tubular element, characterized in that said sealing means is constituted by a removable plug, capable of being housed in sealingly in a cavity provided at the proximal end of the tubular element, and comprising at least two lips (31, 32) elastically deformable.  2 - Trocar according to claim 1 characterized in that the tubular element has at its proximal end a cylindrical cavity and in that the plug is formed by a cylindrical body (25) whose outer surface is suitable for sealingly sealing the inner surface of said cavity.  3 - Trocar according to claim 2 characterized in that the plug has on its outer surface at least one annular protuberance (26, 27, 28) to improve the seal.  4 - Trocar according to any one of the preceding claims, characterized in that the cylindrical body is provided with two lips (31, 32) extending in the distal direction and ending with edges (34, 35) substantially rectilinear transverse.  5 - Trocar according to claim 4 characterized in that said edges (34, 35) meet at rest in a substantially rectangular area in the median plane (33).  6 - Trocar according to any one of the preceding claims, characterized in that the plug also has a substantially transverse sealing membrane (36), pierced by an orifice (37) of a section slightly smaller than the section of the pervasive crossing the trocar.  7 - Trocar according to any one of the preceding claims, characterized in that it also comprises at least one adapter constituted by a tubular element having an outside diameter substantially equal to the inside diameter of the plug and an inside diameter suitable for the passage of a laparoscopic instrument.