Anesthesia gas monitoring: central system or stand-alone?

Two approaches to intraoperative anesthetic gas monitoring exist today. Central, mass-spectrometer-based systems share cost and analyzer time among several remote locations. Stand-alone monitors are usually infrared analyzers and are dedicated to a single monitoring location. The advantages and disadvantages of each are due primarily to the shared versus dedicated approaches. Dedicated analyzers, while limited somewhat by infrared technology, offer uninterrupted, real-time analysis of anesthetic and respiratory gases. Central systems offer excellent monitoring but are limited to periodic updates of each monitored location. This article attempts a complete analysis of these and other factors affecting the use, reliability, and cost effectiveness of these two approaches to anesthesia gas monitoring.