Due to their economical and ecological advantages exclusively rebreathing systems are used in modern anaesthetic workstations. Only in desaster medicine or under extremely poor logistic conditions non-rebreathing systems and draw-over vaporizers may be used alternatively. To extensively use the rebreathing technique, the fresh gas flow can be reduced to just that amount of oxygen equalling the metabolic uptake of the respective patient when one omits the use of nitrous oxide. That renders possible either to use medical gases from gas cylinders or from central gas piping system, or to use small portable oxygen concentrators as a source for oxygen. Only electric current would be needed to run such gas supply. Vaporizers outside the circuit can only deliver limited amounts of inhalation anaesthetics if extremely low fresh gas flows are used. Fresh gas flow independent supply of the anaesthetic by injecting the fluid agent directly into the breathing system, i.e. with the aid of a micro-pump system, may solve this problem. Such a device, too, can be run with electric current and the same delivery system could be used for inhalation and intravenous anaesthesia likewise. The ventilators also should operate with electric current and their performance should be suited to the needs of the respective surgical unit. Very often only the simple IPPV-mode sufficiently will meet the needs, whereas in specialized units different sophisticated modes like SIMV, BIPAP, PCV, or ASB may be needed. New carbon dioxide absorbents, like calcium hydroxide lime or lithium hydroxide, should not react with inhalation anaesthetics, but also alternative techniques like carbon dioxide separation via membranes may become available in future.

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