July 26, 2022 – Masimo recently announced the findings of a randomized, controlled trial published in the Journal of Clinical Anesthesia in which Dr. Melody H.Y. Long and colleagues from the KK Women’s and Children’s Hospital in Singapore evaluated the ability of electroencephalogram (EEG)-guided anesthesia, using Masimo SedLine® brain function monitoring, to reduce the amount of the drug sevoflurane needed to maintain anesthesia in pediatric patients undergoing minor surgery. They found that use of SedLine to guide anesthesia reduced sevoflurane requirements and led to a reduced incidence of burst suppression, which has previously been reported to be associated with postoperative delirium.
Noting the unique nature of pediatric brains, which are still developing, the importance that standard anesthesia practice places on minimizing the dosage of drugs needed to maintain anesthesia, and the lack of research into the use of new technology like real-time EEG spectrogram monitoring in children, the researchers devised a study that would investigate what impact such technology might have. They enrolled 195 children, aged 1 to 6 years, who were scheduled for minor surgery involving general anesthesia induced and maintained using sevoflurane. The children were randomized into either a Masimo SedLine EEG-guided group (n=100) or a standard care group (n=95). In the SedLine EEG group, anesthesiologists used SedLine to help guide administration of sevoflurane, with the goals of maintaining continuous slow/delta oscillations on the raw EEG and spectrogram, avoiding burst suppression, and maintaining a Patient State Index, or PSi – a propriety, processed EEG parameter developed by Masimo – between 25 and 50. In the standard care group, clinicians were blinded to the EEG data.
As their primary outcome, the researchers looked at the average end-tidal concentration of sevoflurane used during induction and maintenance of anesthesia. They found that in the EEG group, the concentration was lower both during induction (4.80% compared to 5.67% in the control group, p=0.003) and maintenance (2.23% vs. 2.38%, p=0.005). As one of their secondary outcomes, the researchers compared the incidence and duration of intraoperative burst suppression, and found that the EEG group had a lower incidence of burst suppression (3.1% vs. 10.9% in the control group, p=0.0440).
The authors concluded, “This is one of the first randomized control trials in the pediatric population showing that EEG-guided anesthesia care utilizing the spectrogram is feasible, and leads to a modest decrease in intraoperative sevoflurane dosage for induction and maintenance in young children aged 1 to 6 years. EEG guidance allows easy visualization of anesthesia-induced changes on the brain in real time, making it possible to determine which individuals require more (or less) anesthetic to maintain unconsciousness and titrate doses accordingly. This may be particularly important in children between 1 and 2 years old, who appear to require a higher concentration of sevoflurane during surgery, as well as in patients at risk of neurological injury. Our findings highlight the importance of EEG monitoring in complementing the current ASA standard monitors, to provide personalized anesthesia care.”