GB2069842A - Surgical sponges - Google Patents

Abstract

A method of detecting surgical sponges remaining within the patient's body following surgery, consists of subjecting the patient to X-Ray radiation to obtain an X-Ray image of the relevant part of the patient. The surgical sponge is formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge as a whole opaque to X-Rays. Also described is a sterile package comprising a sterile surgical sponge formed as above. The plastics composition is preferably a polyurethane foam composition. The heavy metal salt is preferably barytes.

Description

SPECIFICATION Surgical sponges This invention is concerned with surgical swabs and like articles used for soaking up body fluids in surgery, casualty treatment and the like. More particularly it is concerned with the use of sponges for this purpose.

A major problem of concern to the medical profession these days is the possibility of a claim for medical negligence resulting from a surgical swab or the like being retained within the patient's body. Heretofore the only method we know to have been employed to detect with any certainty whether this has occurred has been an operation which is of necessity subjects the patient to a second trauma, and may itself lead to a claim for damages or, by virtue of the pain and discomfort inevitably caused, greatly increase the level of any award for damages.

There is a very substantial need for a method which would detect any retained swabs with virtual certainty and without a need for surgery, but until the present invention no such method has been available.

In accordance with a first aspect of the present invention, there is provided a method of detecting surgical sponges remaining within the patient's body following surgery, which method consists of subjecting the patient to X-Ray radiation to obtain an X-Ray image of the relevent part of the patient, the surgical sponge being formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge as a whole opaque to X-Rays.

We also provide, in a second and alternative aspect of this invention, a sterile package comprising a sterile surgical sponge formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge opaque to X-Rays.

In the practise of th is invention, any suitable foamed plastics composition may be used for the sponge, that is: a composition which yields a flexible open sponge capable of soaking up body fluids and which is compatible with body tissues, though (of course) the required quantity of the heavy metal salt will need to be added as filler. Any conventional fabrication technique applicable to the chosen composition may be employed. The shape, size, density and configuration of the sponges produced may vary widely, and will in practise be selected according to the particular surgical or medical application intended for the sponge.

It is believed unnecessary to give a detailed account herein of the various types of plastics foam composition or the fabrication techniques which may be used therefor since the reader will doubtless be fully familiar with these and can, in any case, find all he requires in any of the standard works such as "Plastics Foams" Part I and Part II, edited by Kurt C.

Frisch and James H. Saunders and published by Marcel Dekker Inc., New York.

We have found polyurethane foam compositions to be particularly convenient. These are dealt with at length in Chapter 3 of the above work which is entitled "Flexible Polyurethane Foams" and consists of an article written by G. T. Gmitter, H. J. Fabris and E.

M. Maxey, which gives practical examples of suitable compositions for a variety of purposes.

In order for such compositions to be useful for our purposes, a requisite account of a salt of a heavy metal which absorbs radiation at X-ray wavelengths must be present as filler or substituted for part of the conventional filler. Barium is the most suitable heavy metal and its sulphate- barytes - is ready available and, indeed, already sometimes used as a filler for polyurethane foam compositions. The amount required of the metal salt to render the sponge opaque to X-rays can readily be established by simple experimentation. We have found that a barium sulphate content in the region of 30 parts by weight per 100 parts by weight of prepolyol in a polyurethane composition gives good results, but the invention is not limited for this specific proportion.

The foam produced, for example by reaction between diisocynate and prepolyol in a polyurethane composition with the appropriate filler, must be formed under sterile conditions and packaged in a sterile package, which package may take any of the conventional forms of such packages for surgical cotton swabs, before the resultant sponge is acceptable under modern medical standards for surgical, casualty and like use.

By way of example only we list below a preferred polyurethane foam composition we have found useful in the practise of the present invention, though other feasible plastics compositions will readily occur to the man skilled in the plastics foam art in the light of this present disclosure.

Example Component Parts by Weight Polyol 100.00 Tolylene Diisocyanate 34.40 Water 2.30 Stannous Octoate 2.42 Catalyst-Triethylamine 0.53 Tin 0.21 Silicone 0.35 Blowing agent Trichloromonofluoromethane 7.00 Barium Sulphate 30.00 By way of further illustration, reference should be made to the accompanying drawing, in which the single figure thereof schematically illustrates the application of the method of the present invention to the detection of a surgical sponge 1 retained within the abdomen of a patient 2 after abdominal surgery.

The patient's abdomen is exposed to a conventional source of medical X-rays 3 in an entirely conventional manner for taking medical X-rays. The X-rays after passage through the patient's body are incident upon photographic film or paper 4 sensitive to X-rays to leave a latent image including a latent image 5 of the swab 1. The film ofpaper4isproces- sed in conventional fashion to produce an X-ray photograph on which the swab will be clearly visible provided that the swab 1 is formed from a foamed plastics material the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-ray wavelengths to render the sponge as a whole opaque to X-rays.

Claims (10)

1. A method of detecting surgical sponges remaining within the patient's body following surgery, which method consists of subjecting the patient to X-Ray radiation to obtain an X-Ray image of the relevant part of the patient, the surgical sponge being formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge as a whole opaque to X-Rays.

2. A method as claimed in Claim 1, wherein the plastics composition is a polyurethane foam composition.

3. A method as claimed in any preceding Claim, wherein the heavy metal is Barium.

4. A method as claimed in Claim 3, wherein the Barium salt is Barytes.

5. A sterile package comprising a sterile surgical sponge formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge opaque to X-Rays.

6. A sterile package as claimed in Claim 5, wherein the plastics composition is a polyurethane foam composition.

7. A sterile package as claimed in Claim 5 or 6, wherein the Barium salt is Barytes.

8. A sterile package as claimed in Claim 7, comprising a sterile surgical sponge formed from a foamed plastics the composition of which includes sufficient of a salt of a heavy metal which absorbs radiation at X-Ray wavelengths to render the sponge opaque to X-Rays.

9. A method of detecting surgical sponges remaining within the patient's body following surgery, substantially as herein described with reference to the foregoing example and the accompanying drawings.

10. A sterile package as herein described with reference to the foregoing example.