GB2205675A - A surgical procedure training device - Google Patents

Abstract

A surgical procedure training device which simulates the anterior aspect of the human neck region to permit techniques such as cricothyrotomy to be practised, comprises a section 1 of an animal airway including an epiglottis 2 attached to a length of trachea 3 and a covering of animal skin 4 to be wrapped at least partly around the neck region of a manikin or other member simulating a human neck region, and means for securing the wrapped skin covering in position stretched over the airway section. The device can be preserved in a solution of sodium chloride, potassium chloride, calcium chloride, sodium bicarbonate, benzakonium chloride and glycerine. <IMAGE>

Description

TITLE: A SURGICAL PROCEDURE TRAINING DEVICE Description The invention relates to a surgical procedure training device and more particularly to a device to assist the training in surgical techniques relating to cricothyrotomy.

A problem which arises in training operatives in the First Aid technique of cricothyrotomy is that although the technique is simple in theory it is not something which can be practised on volunteers because of its attendant risks. Neither is there always a convenient supply of cadavers on which to practise the technique. Thus it is often the case that when a doctor or paramedic first encounters a patient needing urgent First Aid treatment to relieve an obstructed airway, he or she will often not have practical experience of the required technique. An incorrectly administered cricothyrotomy can cause trauma to the vocal cords or to the posterior tracheal wall. It is a fact that many persons suffering severe head injuries will die shortly after the injury is inflicted due to the inability of those rendering First Aid to relieve an obstructed airway.

It is an object of the invention to provide a device simulating the anterior aspect of the human neck region and on which the technique of cricothyrotomy can be practised by a trainee.

According to the invention a surgical procedure training device which simulates the anterior aspect of the human neck region to permit techniques such as cricothyrotomy to be practised, comprises a section of an animal airway including an epiglottis attached to a length of trachea and a covering of animal skin adapted to be stretched over the airway section, the skin covering being of a size and shape adapted to be wrapped at least partly around the neck region of a manikin or other member simulating a human neck region, and means for securing the skin covering in position stretched over the airway section. The airway section may be taken from any species having an airway which resembles the basic physiology of a human airway and is preferably taken from the group of animal species consisting of pigs, sheep, goats and kangaroos.Airway sections taken from pigs are readily available and closely resemble the human airway. Preferably the skin covering is of pig skin, since again this is readily available and provides a good simulation. The airway section may be secured directly to the skin covering, e.g. by means of sutures or clips. The skin covering may be provided with opposite edge portions adapted to facilitate the fixing of the device to the neck of a medical manikin or other neck simulating member. For example the opposite edge portions of the skin covering can be provided with ties.

Thus the skin covering may be rectangular in shape and is preferably provided with ties at opposite edge portions to facilitate the fixing of the device around the neck of a medical dummy.

From another aspect the invention is a method of preserving a surgical procedure training device of the kind described above, comprising immersing the device in Ringers solution modified by the addition of glycerine in an amount sufficient to maintain the skin covering in a soft condition and by the addition of an antimicrobial composition in an effective amount.

Preferably the anti-microbial composition is benzakonium chloride. Preferably the method comprises freezing the device while immersed in the modified Ringers solution, and preferably the frozen device is held at around -18 degrees Centigrade.

The invention is diagrammatically illustrated by way of example in the accompanying drawing. In the drawing an animal airway section 1, comprising an epiglottis 2 with an attached length of trachea 3, which may for example be around 50 mm in length, is attached by means of sutures (not shown) at opposite ends to a rectangular skin covering 4. The dotted lines 6 around the airway section 1 are meant to denote that the airway section will in practice be disposed behind the skin and with the anterior wall of the trachea adjacent to the skin covering 4. Opposite edges of the skin covering 4 are perforated to receive laces or ties 5 by means of which the skin may be wrapped around the neck of a medical manikin or dummy or other member simulating a human neck region and secured in position to permit the device to be used in training in cricothyrotomy techniques.

The animal airway will normally be obtained from animals slaughtered for meat and found fit for use as human food. After normal dressing on the slaughter line the airway is removed to include the section above the epiglottis and including about 50 mm of trachea below the cricoid cartilage. The normal source will be from pigs. Also the normal source of the skin covering is from pigs. A rectangular section of pig skin of some 90 mm by 320 mm is removed from a suitable area of the pig carcass and is dehaired mechanically and the subcutaneous fat reduced so as to adjust the thickness of the material to about 4 mm. It is preferred-not to dehair the pig skin by singeing since this adversely affects the texture of the skin.

The airway section is firmly attached to the centre of the skin covering by means of sutures or clips. A firm attachment can be obtained by the application of a suture at the base of the severed trachea and by the application of sutures on each side of the tip of the epiglottis.

The device is packed into a suitable container so as to be completely immersed in a solution made up as a modification to Ringers solution. A solution of formalin is unsuitable since it adversely affects the texture of the skin covering and thus reduces the effectiveness of the simulation. The preferred solution is set out below: EXAMPLE Deionised Water 1,000 grams Sodium Chloride 2.25 grams Potassium Chloride 0.105 grams Calcium Chloride 6H20 0.12 grams Sodium Bicarbonate 0.05 grams Benzakonium Chloride 0.1 grams Glycerine 0.1 grams The Ph value of the solution is adjusted to neutrality and the sealed packs are then frozen and held at around -18 degrees Centigrade until required for use.

When required for use the packs are defrosted at room temperature for some twelve hours and when the device is completely free from ice the solution is drained from the container and discarded. The device is then removed from the packing, rinsed in cold tap water and excess moisture removed before being applied to a resuscitation manikin. In use the device is positioned about the neck of the manikin and fixed in position by means of the ties, so that the skin covering is stretched over the airway section to reveal the "landmarks" of airway to the trainee.

Thus the device provides a training simulation of the anterior aspect of the adult human neck with its underlying larynx and the upper end of the trachea.

The device can be used to practise cricothyrotomy using a variety of laryngostomy or tracheostomy tubes for example a "Minitrach II" device or a Cuffed, Gauge 6, Tracheostomy Tube.

All of the tissue used in the manufacture of the device derives from animals fit for, and intended for, human consumption. Since the device is preserved in a suitable solution it permits repeated and prolonged freezing of the device for storage purposes. The device can be intubuated several times after the initial intubuation and still provide useful training in the feel of the procedure, the arrangement of the tissue planes and direction of insertion of the tracheostomy tube. After a training session the device can be dissected to reveal any intubuation trauma to the vocal cords or posterior tracheal wall.

The device accurately simulates the cold clammy feeling of skin of an accident victim and provides a good simulation of the palpable anatomical landmarks of an adult human neck. The natural elasticity of the device allows it to follow the extension or flexion of the manikin's neck revealing or masking the anatomical landmarks as in real life It is quite easy to canulate the subcutaneous space alongside the trachea thus exemplifying one of the pitfalls of the cricothyrotomy procedure. The device is relatively cheap to produce and disposable thus allowing the maximum number of students to practise the initial knife cut into the neck. Furthermore the device is quickly attached and removed from any adult size manikin. Also there is no risk of infection (HIV and HB antigen free) despite the use of animal tissue with its inherently superior tactile simulation compared to plastics materials.

Claims (14)

1. A surgical procedure training device which simulates the anterior aspect of the human neck region to permit techniques such as cricothyrotomy to be practised, comprising a section of an animal airway including an epiglottis attached to a length of trachea and a covering of animal skin adapted to be stretched over the airway section, the skin covering being of a size and shape adapted to be wrapped at least partly around the neck region of a manikin or other member simulating a human neck region, and means for securing the skin covering in position stretched over the airway section.

2. A surgical procedure training device according to claim 1, wherein the airway section is taken from the group of animal species consisting of pigs, sheep, goats and kangaroos.

3. A surgical procedure training device according to claim 1 or claim 2, wherein the skin covering is of pig skin.

4. A surgical procedure training device according to any preceding claim, wherein the airway section is secured directly to the skin covering.

5. A surgical procedure training device according to claim 4, wherein the airway section is secured directly to the skin covering by means of sutures or clips.

6. A surgical procedure training device according to any preceding claim, wherein the skin covering is provided with opposite edge portions adapted to facilitate the fixing of the device to the neck of a medical manikin or other neck simulating member.

7. A surgical procedure training device according to claim 6, wherein the opposite edge portions of the skin covering are provided with ties.

8. A surgical procedure training device substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

9. A method of preserving a surgical procedure training device according to any preceding claim, comprising immersing the device in Ringers solution modified by the addition of glycerine in an amount sufficient to maintain the skin covering in a soft condition and by the addition of an anti-microbial composition in an effective amount.

10. A method according to claim 9, wherein the anti-microbial composition is benzakonium chloride.

11. A method according to claim 9 or claim 10, wherein the composition of Ringers solution is substantially as set out in the accompanying example.

12. A method according to any one of claims 9 to 11, comprising freezing the device while immersed in the modified Ringers solution.

13. A method according to claim 12, comprising holding the frozen device at around -18 ' degrees Centigrade.

14. A method according to any one of claims 9 to 13, substantially as hereinbefore described.