Anesthesia systems.

Anesthesia systems are used to induce general anesthesia during surgery. In addition, the systems track anesthetic agent and gas concentrations, as well as the patient's condition, using physiologic and multigas monitors. For this Update Evaluation, we present our findings for four newly evaluated models from two manufacturers and summarize our findings for the two previously evaluated models that are still on the market. (Our earlier Evaluations were published in the May-June 1996 and January 1998 issues of Health Devices.) As in the previous Evaluations, our ratings are based largely on the degree of system integration, the suitability of the systems for various types of procedures, and cost. When equipped with the appropriate monitors, all the systems can deliver anesthesia effectively and can meet the minimum monitoring requirements of general surgery. While no system met all our criteria, any limitations of the systems can easily be overcome by the purchaser. We rate two models Preferred. One provides performance and features similar to the other evaluated systems at a significantly lower cost. The second offers exceptional flexibility in meeting monitoring requirements. Three models are rated Acceptable, and the remaining model is rated Acceptable (with Conditions). It is Acceptable only if it is equipped to supply air as an inspired gas.