Abstract
The technical advancement in the anaesthesia workstations has made the peri-operative anaesthesia more safer. Apart from other monitoring options, respiratory gas analysis has become an integral part of the modern anaesthesia workstations. Monitoring devices, such as an oxygen analyser with an audible alarm, carbon dioxide analyser, a vapour analyser, whenever a volatile anaesthetic is delivered have also been recommended by various anaesthesia societies. This review article discusses various techniques for analysis of flow, volumes and concentration of various anaesthetic agents including oxygen, nitrous oxide and volatile anaesthetic agents.