Target controlled infusion: TCI.

Progress in computing technology has allowed the development of target controlled infusion devices, with drugs delivered to achieve specific predicted target blood drug concentrations. Target controlled infusion (TCI) system has been developed as a standardised infusion system for the administration of opioids, propofol and other anaesthetics by target controlled infusion. A set of pharmacokinetic parameters has been selected using computer simulation of a known infusion scheme. The selected model is incorporated into a computer-compatible infusion pump. Clinical trials with such systems have provided appropriate target concentrations for the administration of target controlled infusion of anaesthetic drugs. The technique of TCI strongly influences the development of intravenous anaesthesia and opens a scenario of new and exciting applications in peri-operative anaesthetic management. The launch of ''Diprifusor'' as the first commercially available TCI system for propofol was the cornerstone of a successful research period within the last decade, which evaluated the pharmacokinetic foundations of computer assisted intravenous drug delivery. Nowadays TCI technology is becoming a part of routine anaesthesia technique for the practitioner rather than a research tool for specialists and those who are enthusiasts of intravenous anaesthesia. Besides clinical application in anaesthesia, target controlled systems will play a significant role as research tools in the evaluation of drug interactions in anaesthesia and in the development of new control techniques for the administration of sedative and analgesic drugs in the peri-operative period.