GB2267023A - Surgical thimble - Google Patents

Abstract

A surgical thimble 1 for needle stick protection comprises a flexible needle point resistant element adapted to conform to a digit to provide a continuous barrier to needle stick over a portion at least of said digit. The resistant element comprises a continuous corrugated configuration 2, 4 terminating in a needle point resistent end-cap 3. The cross-sectional shape of the corrugations may be of V-form (Fig. 6), Z-Form (Figs. 4 and 5) or "top-hat" form (as shown). <IMAGE>

Description

2267023 SURGICAL TI-IIMBLE The present invention relates to a surgical

thimble or glove.

The problem of needle stick in surgery is similar to the situation whereby a doctor is accidentally injured with a hypodermic needle which may or may not be contaminated with a highly infectious disease such as AIDS. In surgery, the nature of the injury is similar but, in surgery, the environment is bloody and a sharp suture needle is more likely to cause injury to the surgeon than a hypodermic needle to the doctor. Other diseases present in the environment of surgery may contribute to the added danger of suturing.

It has been the practice to utilise extra gloves to provide a little more protection, but being formed of latex such gloves offer an extra safeguard only against a superficial needle prick.

Full protection for a digit is needed so the surgeon can suture efficiently by holding tissue as required and taught in surgical training procedures, without the fear of needle stick in a digit involved in applying pressure to, or holding tissue during suturing, or any other procedure involving a sharp device.

A sewing thimble is commonly used by surgeons, but it is obviously limited in its action and its rigidity precludes extension further up the digit. Protection against the penetration of a needle must be by means of a material which is sufficiently hard to resist sharp needle penetration, while the material must also be flexible to an extent. As will be appreciated the point load on a suturing needle is very high, particularly where the suturing needle is required to pass through tough tissues during the suturing operation.

Accordingly it is difficult to provide an absolute protection in all circumstances. What is possibly more important is to provide a material which, even if marginally pierced by the suturing needle, is sufficiently strong to prevent the tip of the needle piercing the surgeon's skin, while at the same time alerting him to the presence of the needle tip.

needle.

Plastics materials may be utilised to protect the skin against needle stick; these allow flexibility, but without pores or gaps large enough to allow the entry of a sharp needle point such plastics sheet material is of limited utility because it is not flexible enough.

Metals are ideal, may be sterilised, and may be non-corrosive. Stainless steel is an ideal metal since it is autoclavable and is non-toxic during its temporary contact with tissue.

Metals also have the advantage of being radio-opaque in case of accidental loss into the body during surgery. Plastics in such circumstances require to be rendered radio-opaque by the addition of a media such as barium sulphite or bismuth. It has been found that gloves formed of a needle protective material do not provide the. quality of flexibility is required of a glove for surgical uses.

This invention is primarily concerned with surgical thimbles particularly for the digits such as the index finger and thumb which may be interconnected or separate. By use of protective devices the surgeon may then decide how tissue may be controlled in a procedure involving sharp devices so that the fingers of thumbs used are protected against injury.

US-A-4864661 provides a surgical glove with needle point resistant patches thereupon. These patches may be formed of a woven material or of a solid shaped material as 2 desired. Because solid shaped materials do not flex and bend adequately upon movement of the surgeon's fingers, the segments provided in this Patent must necessarily be small. Thus they can only cover a part of the flesh of a digit and accordingly, whereas these gloves are certainly better than no protection at all, they are of limited real utility.

EP-A-320541 similarly provides a surgical glove which is provided with two layers, an under-layer overlying the hand and an over-layer loosely fitted thereto; said over-layer being of a needle resistant material. Again the loose material, while providing a slanificant 4p cl measure of protection, much reduces the certainty with which a surgeon can suture a wound. Further, on gripping a suture between finger and thumb for example, the advantages of such a surgical glove are lost because the over-layer is no longer loose.

Because of the high point- loading of a suture needle point, woven protective materials as discussed in the Prior Art are of limited utility because, inevitably, the needle point will settle in the interstices between the woven filaments. If enough pressure is applied the filaments are forced apart to allow the point of the needle to pierce the surgeon's skin.

This is so whether the woven material is bi-axially or triaxially formed because the woven filaments have a certain amount of movement relative to each other. Accordingly the filaments formin. the protective elements in accordance with the present invention, must be in a substantially fixed inter-relationship to each other. Similarly, where plate-shaped elements are use as needle stick protection, the interstices between adjacent plates must overlap or inter-relate in such a way that the needle point cannot slide between adjacent plates and into the surgeon's skin. These problems have been addressed in co-pending GB A-2259439.

3 According therefore to the present invention there is provided in a first aspect a surgical thimble for needle stick protection, comprising a flexible element adapted to conform to a digit, said flexible element being needle point resistant thereby to provide a continuous barrier to needle stick over a portion at least of a digit, characterised in that the resistant element is formed in a continuous corrugated configuration; preferably in the form of a V shaped, "top-hat" or Z configuration material in cross-section.

In a preferred form of the invention the surgical thimble in accordance with the present invention terminates in a needle resistant end cap of a unitary pre- shaped configuration.

c It will be appreciated that with such a corrugated material, even though it is resistant to needle stick and must therefore be. strong, it is possible to provide a suitable measure of C flexibility, while also providing complete protection for the digit.

Although the V-shaped or the "top-hat" sections provide a significant level of protection, the Z configuration material is often desirable. The Z configuration material, which may be formed by compressing an extruded "top-hat" section material during the forming process, for example, is superior because it provides a substantial well- free upper surface with only a series of circumferential apertures which will only open when digit is bent in a certain direction. Although it is possible for the needle point to enter these circumferential recesses, the needle tip becomes trapped in the shape so formed and hence plenty of warning of presence of a needle tip is provided to the surgeon.

Further because of the unique configuration of the Z configuration's resistant element, the finger may be bent at least as readily as that with the "top-hat" configuration.

4 In order to secure a surgical thimble in accordance with the present invention to a digit, an adhesive may be secured to base material or overlay adjacent the end thereof remote from the protective tip so that the thimble may be secured to a digit. This arrangement is particularly desirable for single use arrangements, although it can be used for re-us cable thimbles where such thimbles can be sterilised and the adhesive provided in a readily renewable form.

In an alternative, the surgical thimble in accordance with the present invention, may additionally be provided with an expansible retaining strap, secured to a wristband about the surgeon's wrist. The retaining strap being expansible can be adjusted to hold the thimble in its correct orientation on the surgeon's finger in the manner of a finger stall.

The needle point resistant material may be formed at least in part from a material selected from polymers, metal-based materials, including metal alloys, ceramics, clastomers, composites and their laminates, other composite combinations or blends. Such composites may include, for example, polymer matrix composites, metal matrix composites, elastomers or rubber based composites and hybrid composites. Suitable examples are, for example, glass fibre strands or KevIar organic aramid fibres. Indeed, any fibre or planar material having a high strength to weight ratio, high impact strength, good RF transparency and good thermal stability and chemical resistance is useful. Similarly, good materials include ballistic nylon, reinforced fibreglass and high modulus polyethylene fibre.

Other needle resistant materials have been described, for example, in The Scientific American, October 1986. Particularly preferred other materials for the practice of this invention include ethylene copolymer materials.

The invention will now be described, by way of illustration only, with reference to the accompanying drawings wherein Figure 1 shows a vertical cross-section of a continuously moulded "top-hat" section protective thimble; Figures 2 and 3 shows "top-hat" section protective elements in accordance to the present invention for use in the arrangement of Figure 1, Figure 4 shows a Z section protective device in accordance to the present invention, Figure 5 shows the Z section in a slightly expanded transverse cross- section, and Figure 6 shows a simple bellows type-protector (V-shaped cross-section) for use in accordance to the present invention.

In accordance with the invention a "top-hat" moulded finger protector (1) is provided with a series of corrugations of which the radially outer surface of the circumferential portion (2) alternates with the radially inwardly disposed recesses (4). The internal diameter of the recesses (4) is adapted for abutment with the digit hence the internal diameter expands slowly toward the open end of the protector so as to accommodate the increasing thickness is of the digit. The end of the protector (1) terminates in a moulded one piece end cap (3) formed of a plastics material. It will be observed that a certain level of flexibility occurs about the points of articulation between the inner and outer circumferential corrugations, and hence a simple finger protector is capable of protecting the finger against needle stick and can be readily provided by this device.

6 Similarly to the arrangement of Figure 1 a V-shaped cross-sectional bellows-type protector (16) of Figure 6 may be provided in a similar fashion and provided with outwardy directed radial portions (17) and inwardly directed radial recesses (19) and the end cap (18). The advantage of the bellows type protector in accordance with Figure 6 is that it is simply made and is more flexible than the arrangement of Figure 1, but the repeated corrugations having a V-shaped configuration tend to result in a reduced sensitivity when utilised during surgical operations.

The arrangement of Figure 1 is shown in enlarged section in Figure 2. A similar arrangement is shown in Figure 3 wherein the "top-hat" sections (5) are formed as a strip.

These maybe either annular as shown in figure 5, or maybe helically formed of an asymmetric strip (6) provided with a means (8) e.g. rivets or welds for securing the strips together at regular intervals above their periphery. The advantage of utilising the riveted arrangement (8) is to enhance flexibility but at some inconvenience in manufacture.

A particularly preferred form of invention is shown in Figures 4 and 5 which provides a is Z- shaped configuration. Although the configuration shown in Figure 4 is more difficult to mould and it may have to be moulded into two steps including a radial compression step after forming it, provides a greater degree of protection. The degree of protection afforded by the Z-section protector (10) lies in the fact that there is provided an outer protective portion (12) and an inner protective portion (14) together forming the Z configuration.

This forms generally a triangular space (15) which both increases the possibility of articulation and provides a trap for a needle-point should it enter the space (15). The arrangement of Figure 4 terminates in an end cap (13) as previsously described.

7 All the arrangements of the present invention can be formed either in a medically acceptable metal such as stainless steel, or of a moulded plastics material as listed herein before. The thickness of the plastics material and the plastics material chosen have to be sufficiently thick to provide protection from a suture needle while being sufficiently thin to allow flexion.

By use of the arrangement in accordance to the present invention it has been found that needle stick can be adequately prevented while allowing the surgeon a sufficiency of feeling in the suturing procedure.

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Claims (6)

1. A surgical thimble for needle stick protection comprising a flexible needle point resistant element adapted to conform to a digit to provide a continous barrier to needle stick over a portion at least of said digit, characteristed in that resistant element comprises a continous corrugated configuration terminating in a needle point resistant end-cap.

2. A surgical thimble according to Claim 1 wherein the element comprises a V shaped, "top-hat", or Z-shaped cross-sectional configuration.

3. A surgical thimble according to either of the preceding Claims wherein the element is formed of a plastics material.

4. A surgical thimble according to either of Claims 1 or 2 wherein the element is formed of a sterilisable metal.

5. A surgical thimble according to any of Claims 1 to 4 provided with an overlay of resilient plastics material.

6. A surgical thimble substially as herein set forth with reference to, and/or as illustrated in, the accompanying drawings.

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