GB2284452A

GB2284452A - Sealing

Info

Publication number: GB2284452A
Application number: GB9324879A
Authority: GB
Inventors: William Henry Yates Franklin; Peter Roland Meldrum
Original assignee: ADVANCED SURGICAL DEVICES LIMI
Current assignee: ADVANCED SURGICAL DEVICES LIMI
Priority date: 1993-12-03
Filing date: 1993-12-03
Publication date: 1995-06-07
Also published as: GB9324879D0

Abstract

A seal (optionally for surgical endoscopic environments), comprising: at least one first resilient seal body or portion (1) having a bore (2) therethrough for sealingly engaging with at least a portion of an object, e.g. an obturator (T); and at least one second resilient seal body or portion (3) spaced apart from and/or touching at least part of said first resilient seal body or portion, the second resilient seal body or portion comprising a resilient tongue or tongue portion (4) that may be flexibly displaced by at least a portion of said passed object from said first resilient seal body or portion, so as to provide a passage through said second seal body or portion for that at least a portion of said object, said flexibly displaced tongue or tongue portion optionally being able to return to or towards its original position (when said object is withdrawn from said seal). The seal may provide sealing against e.g. pressures in the ranges 3 to 20mm and 5 to 15mm of mercury. The seal may be contained in any suitable wall of containment, e.g. a trocar cannula (W). <IMAGE>

Description

SEALING There is continuing need for providing seals in various applications. One application of interest is the provision of seals in surgery, e.g. in surgical endoscopic environments (see later below).

It has now been found in accordance with the present invention that at least one seal may be embodied for providing sealing against gas pressures and/or liquid pressures. The seal may be embodied for any suitable application whether or not in surgery.

A first aspect of the present invention provides at least one seal, comprising: at least one first resilient seal body or portion, having a bore therethough optionally for sealingly engaging with at least a portion of -an object to be passed at least partly therethrough; and at least one second resilient seal body or portion, spaced apart from and/or touching at least part of said first resilient seal body or portion, the second resilient seal body or portion comprising a resilient tongue or tongue portion that may be flexibly displaced by at least a portion of said passed object from said first resilient seal body or portion, so as to provide a passage through said second seal body or portion for that at least a portion of said object, said flexibly displaced tongue or tongue portion optionally being able to return to or towards its original position (when said object is withdrawn from said seal) and thereby optionally seal said bore.

A second aspect of the invention provides at least one seal arrangement, assembly, or system, comprising a plurality of seals of the first aspect of the invention.

A third aspect of the invention provides a kit of parts for providing the first or second aspect of the invention, the kit comprising at least one said first resilient seal body or portion, and at least one said second resilient seal body or portion.

A fourth aspect of the invention provides at least one said first seal body or portion, and/or at least one said second seal body or portion.

A fifth aspect of the invention provides a method of sealing, optionally in surgical endoscopic environments, comprising utilising the first, second, third, or fourth aspect of the invention.

The present invention may be embodied in any suitable manner(s) for any suitable application(s), e.g. for surgical endoscopic trocars (see later below). No restriction is placed upon the seal(s) and their components or manners of use other than suitability for use according to the application(s) required. Any suitable flexible material(s) may be utilised in making seal(s) of the invention. Such materials may be of natural and/or synthetic origin, e.g. chosen from: natural latices, synthetic latices, neoprene rubbers, silicone rubbers, thermoplastic rubbers, polytetrafluoroethylenes,and polyurethanes. The seals may have any suitable shapes and sizes. The seals may be embodied so as to be sterilisable by any suitable sterilising method, e.g. comprising utilising superheated steam, ethylene oxide, or gamma irradiation. Preferably, the seal is not permanently distorted when an object (e.g.

an instrument) is passed therethrough. Preferably, the first seal body or portion and the second seal body or portion do not undesirably interfere with each other, e.g.

a seal body or portion does not invaginate through the other seal body or portion. The flexibility of the seal allows easy entry and passage therethrough of e.g.

instruments, suture needles, etc., and the same when said objects are withdrawn. The flexibility allows such passage without snagging or catching.

When there is a plurality of first seal bodies or portions, the plurality may have different or same shape(s) and/or size(s), e.g. differently shaped or sized bores.

Said bore may have any suitable shape(s) and/or size(s) and/or optional feature(s), e.g. optional wiper lip(s) for providing wiper action on the object when the object is inserted into or withdrawn from a seal.

The resiliency of the tongue or tongue portion should act as memory for its original state so as to aid and/or enable the tongue or tongue portion to return to its original position when said object is removed from the seal.

Said tongue or tongue portion may be shaped in any suitable manner(s), e.g. to aid and/or enable said resiliency memory. The flexibly displaced tongue or tongue portion may have any suitable angles of flexure.

Engagement of the flexibly displaced tongue or tongue portion with the received object may have any suitable shape and area of contact with the received object, (e.g.

any amount of wrapping contact), optionally to engage sealingly with the received object. Some examples of providing the tongue or tongue portion comprise cutting and/or moulding the second seal body or portion.

The overall size of the first seal body or portion and the overall size of the second seal body or portion may change relative to the size of an object received by a said seal. Changes in those overall sizes may change the size of said bore and the size of said tongue.

The present invention may comprise further component(s). For example, at least one seal may further comprise at least one annular washer above and/or below at least one seal body or component. Gas tight sealing and/or liquid tight sealing may be aided by providing permanent and/or temporary lubricant(s) between interfacing surfaces or portions of the seals, e.g. a silicone oil or a "stilting" lubricant, for instance a corn starch. Gas-tight sealing and/or liquid tight sealing may be aided by suitably roughening or profiling interfacing surfaces or portions of the seals.

Any seal of the present invention preferably provides sealing when the seal does not contain the received object. For example, said tongue may act as a flap closing said bore comprised by the first seal body or portion. However, some applications for the invention may not be provided with such closure. Optionally, said bore may itself be closed by resiliency of the first seal body or portion when the object is absent.

In use, at least one seal of the invention may be contained within any suitable "wall of containment", e.g.

tubing or a trocar cannula. The location of the at least one seal may be provided in any suitable manner(s). Some examples of the location may be chosen from one or more of: at least one seal being an interference fit with the wall of containment (for instance when seals are gripped by the wall of circumjacent tubing, etc.); the external peripheries of at least one seal may be seated in at least one optional recess comprised by the wall of containment; the external peripheries of at least one seal may receive or abut at least one optional abutment comprised by the wall of containment (for instance a ridge, shoulder or sill); at least one clip means (for instance a spring clip); or adhesive bonding. In general, permanent or temporary retention of at least one seal within a wall of containment may be provided in any suitable manner(s).

The seal(s) in use may occupy any suitable plane(s), e.g.

seal(s) may be horizontally or substantially horizontally disposed or otherwise angularly disposed.

Any suitable objects may enter into sealing engagement with seal(s) of the present invention, e.g. a said object may be an obturator (see later below) for use with a trocar. Some preferred embodiments of the seal(s) of the invention are especially suitable for providing gas-tight sealing and/or liquid-tight sealing in surgery, preferably in and or relating to endoscopic trocars.

Below is a summary of nomenclature relating to endoscopic applications. Some examples of sealing against pressures are sealing against pressures in the range substantially 3 to substantially 20 mm of mercury or in the range substantially 5 to substantially 15 mm of mercury, such a pressure being able to act so that in some embodiments of the invention the non-displaced or returned tongue or tongue portion may seal the bore in the upper seal body or portion. However, other optional means (e.g. an optional profile comprised by a tongue or tongue portion) may aid or enable such closure, for instance by overlying and/or penetrating said bore.

EXMIPLE Summary Endoscope An Illuminated Optical Viewing instrument used for direct visual inspection of a hollow organ or cavity.

Endoscopv A General term recognised as meaning 'To examine within" Laparoscopy Tb examine within the Abdominal Cavity Thoracoscopv Go examine within the Thoracic Cavity 'I'rocar An instrument used to gain entry to a body cavity. A trocar consists of a Cannula or conduit through which a sharp pointed Obturator is positioned.

The tip of the obturator protrudes further than the end of the cannula when in the working position. This tip may be guarded, or not, depending on the specific usage of the trocar. It provides, when inserted into a body cavity, a conduit through which an endoscope may be inserted to view internal viscera.

Further trocars may be used to enable the entry of surgical instruments. l'hese trocars enable diagnostic or therapeutic procedures to be performed in a "minimally invasive" fashion and thus reduce the morbidity associated with large conventional incisions.

Trocars are available in different lengths and diameters to enable different sizes of instruments to be used. Typical instrument diameters are 5mm/lUmmll2mm/18mm/33mm.

Insertion A trocar is inserted through a body wall using the sharp tip of the obturator.

Once the trocar is inserted, the obturator is then removed leaving the cannula in place, thus creating the means of access into the body cavity.

lnsumation This is the action of inflating a body cavity with Co2 (Carbon Dioxide). 'i'his is carried out to enable the viscera to be viewed more easily, and to allow sufficient space to carry out the surgical procedures. This Co2 inflation is achieved using an insufflation machine which is a pump that inflates to the desired pressure and then maintains the pressure overcoming any loss through leakage during the procedure.

Pneumoperitoneum Refers to insulation within the abdomen.

Pneumothorax Refers to insufflation with the thoracic cavity.

Carbon Dioxide Co2 is the gas of choice for insufflation. It is an inert gas which will not ignite in the presence of sparks associated with dissection methods such as 'Laser' or monopolar diathermy.

Another characteristic of Co2 is that it is easily absorbed into the human body if small pockets of gas are left in the "Gutters" of the abdomen after Desufflation.

Desufflation describes the action off releasing the CO2 from the body cavity after the procedure.

Insufflation Pressure Abdominal cavity: No more than 14mm mercury Thoracic Cavity : No more than 5mm mercury.

Seal A requirement of a trocar used in endoscopic surgery is that it must maintain the Co2 pressure within the body cavity. The seal, which may be one or a series of seals, is used to prevent or minimise gas loss.

It is important to understand that the seal system must maintain insufflation pressure under 2 different conditions : Condition 1: When no instrument is present the seal must be closed to hold insufflation pressure.

Condition 2: When an instrument is in place the seal must circumscribe the instrument shaft to retain the insufflation pressure.

In the accompanying drawings, which are schematic examples of the present invention, and may be utilised in e.g. surgical endoscopy: Fig. 1 shows one example of a composite seal comprising an upper seal body and a lower seal body spaced apart from each other.

Fig. 2 shows the composite seal of Fig. 1 when containing a received object.

Fig. 3 shows one example of a composite seal comprising an upper seal body and a lower seal body touching each other.

Fig. 4 shows the composite seal of Fig. 3 when containing a received object.

Fig. 5 shows one example of a seal arrangement, assembly or system comprising two spaced apart composite seals of Fig. 3.

Fig. 6 shows the seal arrangement, assembly, or system of Fig. 5 when containing a received object.

Fig. 7 shows one example of a unitary seal comprising an upper seal body portion and a lower seal body portion in contact with each other.

Fig. 8 shows the unitary seal of Fig. 7 when containing a received object.

Fig. 9 shows one example of a lower seal body of Fig.l when modified to contain a yieldable aperture, as a further component.

Fig. 10 shows the lower seal body of Fig. 9 when containing a received object.

In Fig. 1, an upper seal body 1 is a disc of suitably flexible material having a central bore 2 (it need not be centrally located in some other embodiments) whose periphery may sealingly engage the periphery of an object T (shown inserted in Fig.2)e.g. an obturator. A lower seal body 3 is a disc of suitably flexible material having a central tongue 4 (it need not be centrally located in some other embodiments). The periphery of the tongue may be provided in any suitable manner e.g. separation 9 provided by using a knife and/or a laser beam, and may have any suitable shapes (e.g. parallel and/or sloping sides or edges). The tongue 4 may sealingly or otherwise engage a portion of the periphery of the object T when that object has displaced the tongue downwards upon the object T being received in the lower seal body 3. Tongue 4 will return to or towards its original position when the object is withdrawn from the lower seal body 3. The returned tongue will act as a flap closing the bore 2.

The upper seal body 1 and lower seal body 3 are located in a wall of containment W constructed by a trocar cannula.

The resilient seal bodies 1,3 may be inserted into wall W and then abut against optional sills 5,6 comprised by the wall of containment, e.g. sill 5 or 6 constructed by a moulding forming part of the wall W and/or an annulus and/or a circumferential clip.

Figs. 3,4 correspond to Figs. 1,2 except that Figs.

3,4 show the upper seal body 1 and lower seal body 3 in touching contact.

Figs. 5,6 correspond to Figs. 3,4 except that Figs.

5,6 show two seals spaced apart from each other.

Fig. 7 shows a unitary seal-comprising an upper seal body portion 21 and a lower seal body portion 23, the portion 21 having a central bore 22, and the portion 23 having a flexible tongue 24. The portions 21,23 and the bore 22, tongue 24 correspond to the items 1,2,3,4 in Figs. 1,2.

Figs. 9,10 show a unitary seal of Figs. 7,8 except that the seal is provided with a yieldable aperture 7 in the hinge region or root region of the tongue 4, such that when the object T is received by the lower seal body 3, yieldable aperture 7 will yield when the passage created by the insertion of object T to displace tongue 4 enables that yielding. The yielding will reduce excess pressure (if any) on the hinge or root region of tongue 4, thereby improving the ability of tongue 4 to return to its original position when object T is removed.

The seals according to the drawings may be embodied for sealing with a trocar used in endoscopic surgery, so that the trocar has a carbon dioxide gas tight seal to that the trocar has a carbon dioxide gas tight seal to enable the retention of a gas insufflation within a body cavity. In general, the present invention as shown in the drawings may be embodied in any suitable manner(s), e.g.

as described before the first reference to the drawings.

The present invention includes equivalents and modifications arising from all the disclosures of the present specification, e.g. from the description given before the first reference to the drawings, and also the disclosures of the drawings. Seal(s) of the present invention may be embodied and utilised in any suitable manner(s) for any suitable walls of containment and applications.

Claims

1. A seal (optionally for surgical endoscopic environments), comprising: at least one first resilient seal body or portion, having a bore therethrough optionally for sealing engaging with at least a portion of an object to be passed at least partly therethrough; and at least one second resilient seal or portion, spaced apart from and/or touching at least part of said first resilient seal body or portion, the second resilient seal body or portion comprising a resilient tongue or tongue portion that may be flexibly displaced by at least a portion of said passed object from said first resilient seal body or portion, so as to provide a passage through said second seal body or portion for that at least a portion of said object, said flexibily displaced tongue or tongue portion optionally being able to return to or towards its original position (when said object is withdrawn from said seal) and optionally seal said bore, said seal optionally providing sealing when said bore does not contain a said object.

2. A seal as claimed in claim 1, wherein at least one said first resilient seal body or portion has a bore therethrough for sealing engaging with at least a portion of said object.

3. A seal as claimed in claim 1 or 2, wherein said flexibly displaced tongue or tongue portion is able to return to or towards its original position (when said object is withdrawn from said seal) and optionally seal said bore.

4. A seal as claimed in any one of claims 1 to 3, wherein said seal is adapted not to distort permanently when said object engages said bore.

5. A seal as claimed in any one of claims 1 to 4, wherein said first seal body or portion and/or the second seal body of portion are adapted not to invaginate through the other said seal body or portion.

6. A seal as claimed in any one of claims 1 to 5, wherein said bore has optional wiper lip(s) for providing wiper action on said object when said object is inserted into or withdrawn from a said seal.

7. A seal as claimed in any one of claims 1 to 6, when contained within a suitable wall of containment.

8. A seal as claimed in claim 7, when said wall of containment is tubing.

9. As seal as claimed in claim 7, when said wall of containment is constituted by a trocar cannula.

10. A seal as claimed in any one of claims 7 to 9, when an interference fit with a wall of containment.

11. A seal as claimed in any one of claims 7 to 9, when the external periphery of said seal is seated in a recess comprised by a wall of containment.

12. A seal as claimed in any one of claims 7 to 9, when the external periphery of said seal receives or abuts at least one abutment comprised by a wall of containment.

13. A seal as claimed in any one of claims 7 to 9, when clipped to a wall of containment.

14. A seal as claimed in any one of claims 7 to 9, when adhesive bonded to a wall of containment.

15. A seal as claimed in any one of claims 1 to 14, when adapted to seal against pressure in the range substantially 3 to substantially 20mm of mercury.

16. A seal as claimed in claim 15, when adapted to seal against pressure in the range substantially 5 to substantially 15mm of mercury.

17. A seal, substantially as hereinbefore described with reference to and as shown in any one of the accompanying drawings.

18. A seal as claimed in any one of claims 1 to 17, when sealing engaging a said object.

19. A seal as claimed in claim 18, wherein said object is an obturator.

20. A seal arrangement, assembly or system, comprising at least one seal as claimed in any one or more of claims 1 to 17.