WO2008006380A1

WO2008006380A1 - A retainer for supporting viscera during open surgery of the abdomen

Info

Publication number: WO2008006380A1
Application number: PCT/DK2007/050090
Authority: WO
Inventors: Nessn Htum Majeed Azawi
Original assignee: Region Hovedstaden V/Herlev Hospital
Priority date: 2006-07-11
Filing date: 2007-07-10
Publication date: 2008-01-17

Abstract

A retainer for supporting viscera during open surgery in the abdomen of a patient, comprising a sheet structure having two sides and a peripheral edge, wherein at least part of said sheet structure is plastically formable to conform with the 5 contour of at least a portion of said viscera being relocated during surgery, and wherein at least part of the sheet structure is see-through.

Description

A RETAINER FOR SUPPORTING VISCERA DURING OPEN SURGERY OF THE ABDOMEN

The present invention concerns a retainer for supporting viscera during surgery and particularly during open surgery of the abdomen of a human or animal patient.

BACKGROUND OF THE INVENTION

During surgery of a patient it must be ensured that the actual site of surgery on the patient is as easily accessible to the surgeon or surgeons as possible, in such a way that the surgeon may perform the surgery in a secure and efficient manner. For example in open surgery in the abdominal cavity of a patient, typically, at least some of the viscera, e.g. the bowel, needs to be temporally dislocated and retained in a dislocated position with respect to its normal position in the abdominal cavity. Prior art surgical techniques require a number of retractors for dislocating and retaining individual parts of the viscera during such surgical procedure. The retractors are often supplemented by whatever means are handy, e.g. surgical napkins etc., in order to provide sufficient support for all parts of the temporarily removed viscera. Typically, at least one and often two or more aids to the surgeon are needed for the purpose of dislocating and retaining the viscera and/or to support the retractors and supplemental items in order to maintain a steady support of the viscera during the entire surgery. This is unfortunate, since the work space available to a surgeon during most surgical procedures is often very limited. The extra personnel who are only or mainly there for keeping the retractors may easily impede proper access for the surgeon to the surgery site. Also, when using a plurality of retractors and other available remedies it is difficult to provide a stable support for the dislocated viscera, which is needed for securing that the viscera is not damaged during surgery. Further, the number of hands and devices used makes it difficult for the surgeon to verify that a stable support for the viscera is obtained and maintained during surgery.

There is thus a need for a device for stably supporting the viscera during open surgery, a device which is easily adjustable and requires few or no extra tools/devices for retaining the viscera, a device which needs no or little human support to maintain correctly positioned during surgery. There is also a need for a device which allows for quick and easy verification that a correct support of all parts of the dislocated viscera has been obtained and is maintained during the entire surgery.

From the field of closed abdominal surgery nets for retaining viscera are known, e.g. as disclosed in FR 2805731 or DE 298 16 298 Ul. These documents disclose nets to be placed and fixed in the abdominal cavity to hold e.g. intestines away from a closed site of surgery. However, the configurations of the nets mean that it is difficult to support specific areas of the viscera more than others, if necessary. Furthermore, it may cause problems to fix the nets without risking damage to the tissue areas used for fixation. Another example of a viscera retainer is disclosed in US 2003/0004473. This retainer comprises an outer envelope of pliable material with sheets of material in the envelope and with an evacuation port for evacuating the envelope to obtain a more rigid structure. Such a solution may provide a better support than nets, but it is not possible, or at least very difficult, to perform any adjustment of the rigid configuration during surgery if needed. Further, this device will not allow the surgeon to verify the correct positioning of the device, and thus to verify that the retained viscera is properly supported.

OBJECT OF THE INVENTION

It is an object of the present invention to provide a retainer which overcomes problems of the prior art. It is a further object of the invention to provide an improved support for viscera during open surgery in the abdomen of a human or animal patient. It is another object of the present invention to provide a retainer which ensures that the supported viscera can be easily surveyed during surgery in order to verify that the optimal support for the viscera is maintained throughout the surgical procedure. It is yet another object of the present invention to provide a retainer that can be easily adjusted during surgery. It is yet a further object of the invention to provide a retainer that allows quick and safe dislocation (repacking) and retainment of viscera during surgery.

SUMMARY OF THE INVENTION

The object of the invention is obtained by a retainer for supporting viscera during open surgery in the abdomen of a patient, comprising a generally two-dimensional sheet structure having two opposed sides and a peripheral edge, wherein at least part of the sheet structure is plastically shapeable to retain and conform with the contour of at least a portion of said viscera being relocated during surgery, and wherein at least part of the sheet structure is see-through, i.e. allows obtaining a visual impression of objects or structures by seeing through the retainer.

Thus, after the initial deformation of the retainer, it may be re-formable to at least one other plastically deformed configuration. Thereby, the viscera can be efficiently supported due to the shapability of the retainer. When the retainer is see-through, the surgeon may easily secure that all parts of the viscera are properly supported, and he may at all times during surgery visually inspect that the viscera remains properly supported. Also, the surgeon may rapidly respond to any irregularities, e.g. bleeding and such, from the supported viscera.

Throughout this document the term "plastically formable" should be understood as the ability of a material to be shaped/transformed from one configuration to another (and back to the original configuration or to a third configuration), and remain in this configuration, by its own nature, without supporting or applying any force to the material to maintain its transformed configuration, and the material requiring a certain force for shaping the material from one configuration to another, in such a way that gravity on the material or the force from e.g. dislocated viscera slipping back into its natural position will not change the configuration of the material.

The sheet structure is preferably formable by hand. This makes it possible to ensure as good a support of the viscera as possible, even if it is appropriate to change the placing of the viscera during surgery. However, it may also be possible to deform the retainer by use of one or more tools either used for other purposes during surgery or made available particularly for this purpose. It is furthermore possible within the scope of the invention that the retainer comprises parts having different mechanical properties and thereby different deformability properties.

The term "formable by hand" in this document should be understood as malleable or formable by a normal adult person without using any tools or excessive force. The see-through properties of the sheet structure may be obtained by letting at least part of the sheet structure be formed in a transparent material, such as a transparent plastic or silicone material.

The see-through properties of the sheet structure may alternatively or additionally be obtained or improved by letting at least part of the sheet structure be formed as a mesh structure with openings.

The meshes may comprise any desired geometry, such as square, rectangular, polygonal or circular, or a combination thereof, and a retainer according to the invention may have a constant mesh geometry or a mesh geometry with different mesh sizes. The mesh size is preferably about 25 mm x 25 mm for use in human abdominal surgery, but depending on the actual use (adult or child, human or animal patient) the mesh size can have other appropriate dimensions. Thus, it is ensured that the sheet structure is see-through, and at the same time does not allow parts of the viscera to be caught in the mesh during surgery, whereby the risk of damages to the dislocated viscera is decreased.

The mesh can be made from and a thread material of a lead/tin alloy having about 40 % lead and 60 % tin and having a thread thickness between 0.5 and 5 mm, such as between 0.5 and 2 mm or between 2 and 5 mm, such as 2.5-3 mm. Other thread materials may be used, since what is important is the mechanical properties of the material.

Preferably, in either of the above embodiments at least an outer surface of the sheet structure is suitable for sterilization. Thus, the sheet structure may be formed in a plastically formable metal, or any other sterilizable, plastically formable material, or a combination thereof in different parts of the sheet structure.

In one embodiment the sheet structure comprises an inner, plastically deformable (or load carrying) layer or a core and an outer layer or coating. Thus, the inner layer may be plastically formable metal, e.g. in a mesh structure or a sheet metal form having apertures in order to make the sheet see-through. The outer layer is preferably a coating formed in a sterile, sterilizable [aseptic] material, in order to minimise the risk of infection in the surgery site. Examples of suitable materials are sterile silicone or sterile plastics. In the embodiment, where the sheet structure comprises a mesh structure, the outer layer or coating may cover only the threads, leaving open mesh-apertures in the sheet structure, or it may be a clear film formed such as to overlay or close some or all of the mesh-apertures of the thread mesh structure. The film can have optical, physical and other properties in common with Incise™ drape and Steri™ drape also used in surgery. Alternatively, some or all of the mesh-apertures of the thread mesh structure can be covered by a net with smaller meshes and with less or even no self-supporting properties, so that the corresponding meshes of the thread mesh structure are sub-frames carrying

The mesh may e.g. be made from load-carrying threads having a thickness of 2-3 mm covered by a layer having a thickness of less than 1 mm. However, any possible combination of mesh sizes and thicknesses of the layers will be covered by the scope of the invention. It will also be possible to have more than two layers.

The load-carrying material of the core may e.g. be a metal or an alloy of metals, a thermoplastic material or a composite material. An example of a possible material is an alloy of lead (Pb) and tin (Sn) in a ratio of e.g. 40/60 weight%, approximately. Alternatively, the lead/tin alloy may comprise a 45/55 weight% or 55/45 weight%, where the former will provide a more flexible or malleable sheet structure and the latter will provide a less malleable sheet structure as compared to the 50/50 weight% embodiment. Other alloys and materials are also conceivable.

In either of the embodiments it is preferred that the peripheral edge is substantially smooth, whereby the risk of damage and possible subsequent infection is minimised. In embodiments where the sheet structure is formed by a mesh structure the smoothness may be provided either via providing a coating (in e.g. a silicone or plastic material) enclosing at least the entire periphery of the sheet structure. However, in order to prevent penetration of such a coating by e.g. cut-off ends of the threads of such a thread mesh structure, the thread mesh structure may be formed having no cutting parts e.g. forming the mesh as a moulded structure or by softening points or burs by polishing, grinding, or heat treatment. Preferably, the corners, where the edges of the sheet structure meet, are rounded and smooth in order to prevent or at least minimize damage to the tissues of the patient during surgery.

In either of the embodiments it is preferred that the sides (or faces) of the sheet structure are substantially smooth, whereby the risk of damage and possible subsequent infection is minimised. In embodiments where the sheet structure is formed by a mesh structure this may be provided either via providing a coating (in e.g. a silicone or plastic material) enclosing at least the sides of the sheet structure. However, in order to prevent penetration of such a coating edges or cracks formed at connected crossing core threads, the thread mesh structure may be formed having no such connected parts e.g. forming the mesh as a moulded structure or by softening points, burs or cracks by polishing, grinding, or heat treatment.

The size of a retainer according to the present invention may be so that a maximum extent across a side of the sheet structure substantially corresponds to the size of the abdominal cavity of a human or animal patient to undergo surgery. In an embodiment the retainer is rectangular. However, the retainer may be formed in other geometrical shapes, e.g. round or oval, or it may be substantially rectangular, having rounded corners. Such a size may in the rectangular embodiment be e.g. in the order of 25 cm x 30 cm by side lengths of the sheet structure, but again, depending on the actual use (adult or child, human or animal patient) the retainer can have other appropriate dimensions. This size is advantageous for e.g. an Ileum surgical procedure. For some types of surgery it may, however, be appropriate to use one or more smaller retainers. In total colostomy, cystectomy or aorta aneurism surgical procedures a 40 cm by 30 cm retainer is suitable. In connection with pelvis or gynaecological surgical procedures a 35 cm by 20 cm retainer is suitable. A 20 cm by 20 cm retainer would be suitable in connection with prostate or gland staging surgical procedures, and may be used as a supplementary retainer during other types of surgical procedures as well. Different sizes of retainers can be obtained either by manufacturing them in the appropriate sizes, or by having one or a few standard size(s) that can be folded to the desired size. DESCRIPTION OF THE DRAWINGS

In the following the invention is described in further detail with reference to the drawings in which Figs. IA and IB show schematically a retainer according to the present invention in an un-deformed and a plastically deformed condition, respectively;

Fig. 2 shows an outline of a patient during surgery, where a retainer according to an embodiment of the invention is used for supporting the viscera of the patient; Fig. 3 shows schematically a retainer having regions formed as a mesh structure.

Fig. 4 shows schematically a retainer having a region pre-formed to a three-dimensional form;

Fig. 5 shows a section through a retainer having an inner layer and an outer layer

Fig. 6 shows a cut-out perspective view of a portion of an embodiment of the retainer shown in Fig. 5 where the retainer comprises a thread mesh structure having a coating providing open meshes, and

Fig. 7 shows a cut-out perspective view of a portion of an embodiment of the retainer shown in Fig. 5 where the retainer comprises a thread mesh structure having a coating completely covering the meshes of a thread mesh structure of the inner layer.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION Fig. 1 illustrates how the plastic deformability of a retainer 1 according to the present invention can be used to form the sheet structure 10 into a deformed configuration. The retainer has two sides 11, 12, of which only one 11 is visible in the figure, and a peripheral edge 13. The retainer 1 is shown with lines 50 to illustrate the deformation more clearly; these lines do not necessarily represent any physical features. However, they may represent a possible embodiment of the invention in which at least part of the retainer is formed as a mesh structure, the lines 50 resembling threads of a mesh. One purpose of such a mesh structure may be to establish or contribute to the deformability of the retainer. Another purpose may be to make the material see-through whereby the viscera can be observed during surgery. Fig. 2 illustrates a retainer 1 supporting viscera 120 such as the bowels being at least partially removed from the abdominal cavity 110 of a patient 100 during open surgery of the abdomen of the patient 100. In the figure the slaps of tissue 5 111, 112 have been parted (in a grossly exaggerated way for the illustrative purpose) to provide access to the abdominal cavity 110. By deforming the retainer 1 to a shape corresponding to the outer geometry of at least a portion 121 of the viscera 120 to be supported, the load on each area of the viscera 120 can be kept to a minimum, whereby the risk of damage to the viscera is also minimised. As

10 can be appreciated from the figure, the pliability and plastic formability of the retainer according to the invention allows the surgeon to manipulate the configuration of the sheet structure 10 of the retainer 1, but keeps the displaced (repacked) viscera in place. In the figure it is shown how viscera, such as bowels, is displaced and retained, as well as other tissues (in the fig. the slaps 111, 112)

15 are displaced and retained during surgery. The retainer 1 is preferably deformable by hand so that the shape of the deformed retainer 1 can be adjusted during surgery. The retainer 1 is illustrated as having a size corresponding largely to the size of the abdominal cavity 110 of the patient 100. However, it is also possible within the scope of the invention that the retainer has a different size, such as

20 being significantly smaller or larger. Such a retainer may e.g. be used when it is only necessary to support less or smaller viscera 120. It may also be used in combination with one or more other retainer(s) when such a set-up is considered to provide a more appropriate support.

25 Fig. 3 shows a retainer 1 in which only a part of the sheet structure 10 is formed as a mesh structure. Hereby it may e.g. be possible to combine a larger stiffness of the parts of the retainer not having a mesh structure and the see-through properties of the mesh structure. In another embodiment of the invention, the retainer has more than one part with mesh structure and these parts have the

30 same or different properties.

In Fig. 1 the whole retainer is illustrated as having a sheet structure. However, another possibility is that only part of the retainer has a sheet structure. An example of such an embodiment is shown in Fig. 4. The purpose of having a part 35 40 of the retainer 1 not being sheet-shaped may e.g. be ease of use by letting part 40 of the retainer be pre-shaped to match specific organ requiring special care being taken. In the figure this pre-shaped part 40 is shown as a cup-shaped part. However, such a pre-shaped part 40 may comprise any desirable shape preferably resembling a particular organ to be retained.

In Fig. 5 a section through a retainer according to an embodiment of the invention is shown. The retainer 1 comprises a sheet structure 10 having two sides 11, 12. The sheet structure comprises a core or inner layer 20 and an outer layer 30. The inner layer is formed in a load carrying and plastically formable material. The outer layer is formed in a sterilizable material such as a silicone or plastic. The outer layer 30 forms a coating, in order to make it sterilizable and/or to cover sharp points, edges or pinching cracks or fissures, that may be present when the inner layer is comprised by a mesh of interwoven or interconnected threads, the threads being connected at mesh points, in order to render the sides 11, 12 and/or edges 13 of the retainer 1 less traumatic to the supported viscera. Sections of such a coating may be formed in a transparent material, and other section may not be see-through.

As shown in Fig. 6, in one embodiment the core or inner layer 20 is comprised by a mesh structure formed in a plastically formable material, e.g. a metal or an alloy, and the outer layer 30 covers the threads 50 of the mesh structure in such a way that apertures 60 are formed, where the meshes of the mesh structures are formed. In Fig. 7 an alternative embodiment is shown, in which the outer layer entirely covers the meshes of the mesh structure in order to form a true sheet. The core can be a mesh of 2.5 mm wire of a lead/tin alloy with 40 % lead and 60 % tin coated by a layer of silicone. The lead/tin alloy gives such a retainer good shape retaining properties and it can be shaped by hand, and the silicone coating gives it a surface with good properties for the intended medical use in human and veterinarian surgery.

However, in another embodiment (which could be resembled by Fig. 1) the entire sheet structure may be formed in a transparent, plastically formable material, e.g. a plastic, or a composite material with similar properties.

Claims

CLAIMS:

1. A retainer (1) for supporting viscera (120) during open surgery in the abdomen of a human or animal patient (100), comprising a sheet structure (10) having two opposed sides (11, 12) and a peripheral edge (13), wherein at least part of said sheet structure (10) is plastically formable to conform with the contour of at least a portion (121) of said viscera (120) and to retain said viscera during the surgery, and wherein at least part of the sheet structure (10) is see-through.

2. A retainer (1) according to claim 1 wherein said sheet structure (10) is formable by hand.

3. A retainer (1) according to claim 1 or 2, wherein at least said see-through part of said sheet structure (10) is formed in a transparent material.

4. A retainer (1) according to any of the claims 1-3, wherein at least part of said sheet structure (10) is formed as a mesh structure.

5. A retainer (1) according to claim 4 wherein the mesh size is about 250 mm or smaller, such as smaller than 10 mm, such as between 1 mm and 5 mm.

6. A retainer according to any of the previous claims wherein at least an outer surface of the sheet (10) is suitable for sterilization.

7. A retainer (1) according to claim 6, wherein said sheet structure (10) comprises an inner, plastically deformable core (20) and an outer layer (30) covering the core (20).

8. A retainer according to claim 7, wherein said outer layer (30) is a coating of a sterile, sterilizable material.

9. A retainer according to any of the previous claims wherein said peripheral edge (13) is substantially smooth.

10. A retainer according to any of the previous claims wherein said sides (11, 12) are substantially smooth.

11. A retainer according to any of the previous claims wherein a maximum extent across a side (11, 12) of said sheet structure substantially corresponds to the size of the abdominal cavity of a person to undergo surgery.

12. A retainer according to any of the previous claims wherein said sheet structure (10) is substantially rectangular.

13. A retainer according to claim 12, wherein side lengths of said peripheral edges (13) are approximately 40 by 40 cm or smaller, such as substantially 40 by 30 cm, such as substantially 35 by 20 cm such as 20 by 20 cm.