Victoria Harris explains the difficulties of using and maintaining anaesthetic equipment in isolated or developing parts of the world; she tells us how a doctor from Gloucester invented and developed a solution

Operating theatres have a distinct sound. Unless dominated by the roar of an orthopaedic chain saw, it is the anaesthetist and his or her monitors that provide that familiar backdrop to the theatre. Bleeping, clunking, suction, and alarm bells reflect the degree of sophistication achieved in modern anaesthetic monitoring--at least in the affluent Western world.

In the United Kingdom, we worry about how we are going to replace thousands of anaesthetic machines without hypoxic guards, but anaesthetists in isolated or less developed parts of the world are grateful for a machine that works at all.

Most modern anaesthetic machines are complicated expensive pieces of equipment costing between £20 000 (a31 066; $31 882) and £40 000. They need high level maintenance and servicing by trained engineers. They rely on the Western luxuries of continuous electricity and compressed gas supplies, not to mention expensive anaesthetic agents. These machines are not suitable for use in difficult circumstances: where they have been introduced into developing countries they have been expensive failures.¹

To provide safe anaesthesia in rural parts of developing countries, where such services are unavailable, specifically designed equipment is necessary. Machines must be robust, inexpensive, and be able to function despite erratic medical supplies, frequent power cuts, and limited facilities for servicing. Despite such a need, doctors continue to direct research at more expensive and elaborate systems. Surely such an attitude is contributing to the enormous global inequalities in health?

While on my anaesthetics placement at Gloucestershire Royal Hospital, however, I came across a doctor whose interest in designing anaesthetic machines was aimed at this unconsidered market--the developing world. He had developed the Glostavent, an anaesthetic machine with a difference. It costs a fraction of the price of an average machine (around £8000),² and has been designed specifically for use in difficult situations.

The Glostavent comprises four separate components.

Draw over vaporiser--Atmospheric air is used as the carrier gas which is drawn over a low resistance vaporiser, either by the spontaneously breathing patient or by the action of the bellows if breathing is controlled. The vaporiser is, therefore, entirely independent of the supply of compressed gases.

Manley multivent ventilator--Driven by compressed air or oxygen, the ventilator needs a driving gas equal to one tenth of the patient's minute volume so that the total volume of gas used is low. Oxygen used for driving the ventilator is automatically collected and then used for the patient to breathe.

Oxygen concentrator--The concentrator produces a continuous supply of oxygen from atmospheric air by compressing the air and absorbing the nitrogen from it.

Air compressor--The air compressor is part of the oxygen concentrator. Some of the compressed air generated by the concentrator is used to drive the ventilator.

These components are mounted on a single trolley together with two reserve cylinders of oxygen and can be used in theatre as an anaesthetic machine or as a ventilator in intensive care units.³

In small children breathing spontaneously, draw over anaesthesia is unsuitable because of the resistance of the apparatus to breathing. In this situation, the Glostavent can be readily converted to a continuous flow machine.²

The Glostavent is not only inexpensive to purchase but also economical to use and maintain. Nitrous oxide is not used for draw over anaesthesia and further significant savings are possible because soda lime and cylinders of oxygen, nitrogen dioxide, and compressed air are not needed. The Glostavent needs little servicing, is simple to operate, and continues to function if the compressed gas supply or electricity is interrupted.

The Glostavent has been used in Zambia, Mozambique, Nepal, and Ukraine as well as at the Gloucestershire Royal Hospital. More recently, the Thanh Hoa Provincial Hospital, Vietnam, received six Glostavents from charitable donations. The hospital would like a further four, so that each of its operating theatres is equipped to provide anaesthetic services despite unreliable electricity supplies.

Marketing such a non-profit making scheme is difficult, especially as the countries that most need Glostavents are least able to afford them. Anaesthetists working in rural locations deserve equipment designed to meet their particular needs, however, and the Glostavent has made an excellent contribution to this cause. The task now is to recommend the machine to those who could most benefit from it. This is not easy as some doctors in the developing world wrongly assume that the West is offering them inferior equipment. The Glostavent is not high tech but it has been designed by people with genuine human compassion and insight into the problems of the developing world. Hopefully its success will continue.

The Glostavent was developed by Dr R Ellingham, and this article appeared with his permission.

1. Ezi-Ashi TI, Papworth DP, Nunn JF. Inhalational anaesthesia in developing countries: part I: the problems and a proposed solution. Anaesthesia 1983;38:729-35.
2. Eltringham RJ, Qui Wei F. The Glostavent: an anaesthetic machine for difficult situations. Traumacare 2001 spring/summer:38-40.
3. Eltringham RJ, Varvinski A. The Oxyvent: an anaesthetic machine designed to be used in developing countries and difficult situations. Anaesthesia 1997;52:668-72.