The purpose of reclassifying breathing systems is to enhance understanding by relating structure to function. A previous classification1 which appears to fulfill this objective is updated to include recent developments in a newly named group of systems called “displacement afferent reservoir” (DAR) breathing systems. A classification table allows for quick comparison and shows that, of the non-absorber systems, the DAR group has the best characteristics of fresh gas utilization.
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ZbindenA.M., FeigenwinterP., HutmacherM.Fresh gas utilization of eight circle systems. Br J Anaesth1991; 67: 492–99.
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