The Influence of Two Different CO2 Absorbers on Sevoflurane Consumption During Anaesthesia

Traditional sodalime CO2 absorbers are known to not only react with CO2 but also with sevoflurane. Therewith, a potentially harmful compound (compound A) is formed that can be nephrotoxic. In the United States, the sevoflurane manufacturer therefore recommends keeping the FGF (FGF) at >2.0 L min-1 if a sodalime CO2 absorbent is used. Amsorb Plus® (Datex-Ohmeda Inc., Madison, WI, USA), is a novel type of CO2 absorbent that does not react with sevoflurane. This allows the FGF to be reduced to 0.5 L min-1. This has two important advantages: (i) less fresh sevoflurane is added to the circle system, and (ii) the sevoflurane that is in the system does not react with the CO2 absorber.

Sevoflurane is a potent greenhouse gas with a 100 year CO2-equivalents of 120. Measures that can reduce the consumption of volatile anaesthetics could make a significant contribution to reducing the carbon footprint of the operative process. Additionally, Amsorb Plus® canisters seem to have a longer life span than sodalime canisters and do not need to be disposed of via toxic waste stream, but via domestic waste.

In this study, we were interested if (i) the use of Amsorb Plus leads to a reduction in sevoflurane usage and therefore contribute to a reduction in the CO2 footprint of general anaesthesia with sevoflurane, (ii) Does the use of Amsorb Plus® lead to a reduction in the amount of (toxic) waste produced by operating theatres?

Comparator: a traditional sodalime CO2 absorber (Medisorb™ Multi-Absorber Original, CareFusion, Helsinki, Finland).