Anesthesia delivery via manual control versus end-tidal control: A scoping review

This scoping review examined available evidence, including usability, efficiency, and accuracy, on the delivery of general inhaled anesthesia with End-tidal Control (EtC) versus manual methods. Data was extracted to identify consistency in measurements used, trends in subsequent outcomes, and areas for further study. Twelve studies were identified: six (50.0 %) were randomized controlled trials. Nine studies (75.0 %) evaluated usability outcomes, eight (66.7 %) assessed efficiency-related outcomes, and six (50.0 %) compared the accuracy of target-level maintenance during anesthesia, between EtC and manual control. Overall, 66.7 % (n = 6) of studies assessing usability found EtC required less than half as many provider interventions than manual control. The majority of studies found EtC performed as well or better than manual control, rapidly reaching target concentrations of anesthetic agent or oxygen. Four out of five studies evaluating the duration of concentration deviations found that EtC maintained concentrations within 10 % of targets for at least 90 % of the duration of delivery. Studies evaluating clinician feedback favored EtC over manual adjustments. The findings of this review can inform anesthesia providers regarding the potential implications of using EtC for automated anesthesia delivery. Future research should provide additional prospective/randomized data from large samples, mimicking existing variables to allow continuity and quantitative synthesis.