The best indices of anaesthesia depth monitored by electroencephalogram in different age groups

Introduction: Current electroencephalogram (EEG) indices for monitoring the depth of anaesthesia have not been adjusted for age. This study aims to identify the most suitable EEG indices for monitoring anaesthesia depth across different age groups.

Method: In here, we conducted a prospective observational trial to observe whether different EEG features in different age groups can detect anaesthesia depth and compare their performance.

Results: In Group 1, absolute θ had the highest prediction probability (Pk) value (0.78 ± 0.07), while relative γ had the lowest relative coefficient of variation (CV) value in states 1 (0.160), 2 (0.153), 3 (0.214) and 4 (0.144). In Group 2, absolute θ had the highest Pk value (0.81 ± 0.09), and relative γ had the lowest CV value in states 1 (0.159), 2 (0.178), 3 (0.140) and 4 (0.095). In Group 3, absolute δ had the highest Pk value (0.79 ± 0.08), with absolute slow wave having the lowest CV value in States 1 (0.196), 2 (0.258), 3 (0.295) and 4 (0.181). In Group 4, absolute δ had the highest Pk value (0.75 ± 0.10), and absolute slow wave had the lowest CV value in States 1 (0.176), 2 (0.192), 3 (0.185) and 4 (0.144).

Conclusion: In this study, we found that absolute θ and relative γ are the most suitable choices for young and middle-aged patients, while absolute δ and absolute slow wave are the most suitable choices for young elderly and elderly patients.