In UK oxygen cylinders are black with white shoulders. An oxygen concentrator is a device which extracts oxygen from atmospheric air using canisters of zeolite. Nitrogen is filtered out and oxygen produced. The function and successful economics were described in detail. When ether is used, the oxygen concentrator should be positioned 1.5m above the floor.
Hypoxia is a deficiency of oxygen at the tissue level.
Traditionally, hypoxia has been divided into 4 types. Stagnant or ischaemic hypoxia in which blood flow to the tissues is so low that oxygen is not delivered to the tissues despite normal arterial oxygen tension and Hb concentration. Histotoxic hypoxia in which oxygen is delivered to the tissues but a toxic agent prevents the cells using the oxygen. Recognition of hypoxia. Recognition of tissue hypoxia is not always easy as there are a number of different signs and symptoms.