By the term “medical gases”, we mean a complex of engineering solutions and equipment, consisting of sources of “medical gases”, pipelines, automation systems, dispatching, alarm systems, automatic supply systems, and consumption points of “medical gases”. In our opinion, the term somewhat inaccurately defines the essence of the issue, so we divide it into two components.
The first is the “medical gas supply system” as an engineering complex, the task of which is:
- storage of medical gases in a medical institution,
- delivery of medical gases through engineering networks to the consumer in a medical institution,
- disposal of waste medical gases.
The second is actually medical gases in liquefied or compressed gaseous form in cylinders or cryogenic vessels, which are produced and delivered by specialized companies and factories.
The use of medical oxygen, nitrous oxide, carbon dioxide, compressed air and their mixtures has become the standard in any medical institution. The composition of medical gas mixtures can be adapted to each specific clinical situation, for example, gas mixtures such as oxygen+carbon dioxide, oxygen+helium or xenon, etc. are often used. Be that as it may, the use of any medical gas requires specialized equipment, both engineering and medical, which together can be called a medical gas supply system.
Each medical gas supply system consists of a source of the corresponding medical gas, pipelines transporting medical gas, a supply control system and points of consumption of medical gases.
Almost all medical gases used in medicine are supplied to hospitals in a compressed gaseous state. Medical oxygen is supplied in a liquid or gaseous state.
To store medical oxygen in a liquid state in medical institutions, cryogenic tanks with an evaporator, the so-called gasifiers, are used, with the obligatory use of a backup oxygen source, a balloon bundle – an oxygen train.
To store oxygen in small hospitals, high-pressure oxygen cylinders are used, combined into a single system through a ramp. Medical gas comes from the source through an adjustable high-pressure reducer with a safety valve and indicating pressure gauges (before and after the reducer), where the inlet pressure of the system is reduced to a level acceptable for input into the gas distribution system of the healthcare facility. The gas distribution system usually consists of pipes made of seamless copper pipe or stainless steel, through which the medical gas is delivered to the consumer.
Medical gas pipelines must be designed so that medical personnel and hospital patients do not have direct contact with medical gas supplies. Cylinders and containers for storing gases should be stored in rooms specially equipped for this. All medical gas supply systems require increased attention to safety and must be equipped with alarm systems and control and shutdown devices. In the event of a fire or explosion threat, these systems must be able to quickly disconnect the building from the medical gas supply.
The medical gas supply system should include an electronic control and alarm system that continuously monitors the pressure in the pipelines.
In treatment rooms, final consumption valves (separately or as part of consoles) with standard instant-on gas sockets for connecting special end devices (flowmeters with humidifiers, nebulizers, respiratory support devices, etc.) should be installed. Medical gas supply systems should be equipped with a sufficient number of special end devices for a given medical institution.
After the installation of the gas supply system and its testing with the preparation of relevant acts, the technical and medical personnel of medical institutions must undergo appropriate training and be instructed in the safe operation and maintenance of the equipment.
It must be remembered that in each medical institution the medical gas supply system in one form or another is exclusive. Each medical institution has its own characteristics and, accordingly, has its own system of medical gases that may be different from others. However, there are general principles for constructing a medical gas supply system that must be observed in any healthcare department.