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Published on: January 13, 2018
Impact of age on both BIS values and EEG bispectrum during anaesthesia with sevoflurane in children
E Wodey1, O Tirel, J Y Bansard
1Department of Anaesthesiology and Surgical Intensive Care 2, Hospital Pontchaillou, Rennes, France. eric.wodey@chu-rennes.fr
Insights
The bispectral index (BIS) and EEG bispectrum are linked to children's age during sevoflurane anesthesia, indicating age influences depth of anesthesia monitoring.
Area of Science:
- Anesthesiology
- Neuroscience
- Pediatric Medicine
Background:
- Monitoring depth of anesthesia in children is crucial.
- The Bispectral Index (BIS) and electroencephalogram (EEG) bispectrum are used for this purpose.
- Understanding the relationship between age and these monitoring tools is important.
Purpose of the Study:
- To investigate the relationship between children's age, BIS values, and EEG bispectrum during sevoflurane anesthesia.
- To determine if age influences the interpretation of BIS and EEG bispectrum during anesthesia.
Main Methods:
- Recorded BIS and raw EEG in 100 children at 1 MAC sevoflurane.
- Analyzed the EEG bispectrum using MATLAB, dividing it into 36 frequencies of coupling (MatBis).
- Employed Multiple Correspondence Analysis (MCA) and Hierarchical Ascending Classification (HAC) to analyze MatBis patterns and group children by age and BIS.
Main Results:
- BIS values ranged from 20-74 (median 40) at 1 MAC.
- Age and BIS values correlated along the same axis in the MCA, with MatBis patterns explaining differences.
- Six age-related groups were identified; younger children had higher BIS values (median 54-55) than older children (median 29).
Conclusions:
- The EEG bispectrum and BIS are significantly related to children's age during sevoflurane anesthesia at 1 MAC.
- Age is a key factor influencing BIS values and EEG bispectrum patterns in pediatric anesthesia.
- These findings suggest age-specific considerations may be necessary when interpreting BIS and EEG bispectrum in children.
Background:
The aim of this study was to evaluate the potential relationship between age, BIS (Aspect), and the EEG bispectrum during anaesthesia with sevoflurane.
Methods:
BIS and raw EEG were recorded at a steady state of 1 MAC in 100 children, and during a decrease from 2 to 0.5 MAC in a sub-group of 29 children. The bispectrum of the EEG was estimated using MATLAB software. For analysis, the bispectrum was divided into 36 frequencies of coupling (P(i))--the MatBis. A multiple correspondence analysis (MCA) was used to establish an underlying structure of the pattern of each individual's MatBis at 1 MAC. Clustering of children into homogeneous groups was conducted by a hierarchical ascending classification (HAC). The level of statistical significance was set at 0.05.
Results:
At 1 MAC, the BIS values for all children ranged from 20 to 74 (median 40). Projection of both age and BIS value recorded at 1 MAC onto the structured model of the MCA showed them to be distributed along the same axis, demonstrating that the different values of BIS obtained in younger or older children are mainly dependent on their MatBis. At 1 MAC, six homogeneous groups of children were obtained through the HAC. Groups 5 (30 months; range 23-49) and 6 (18 months; range 6-180) were the younger children and Group 1 (97 months; range 46-162) the older. Groups 5 and 6 had the highest median values of BIS (54; range 50-59) (55; range 26-74) and Group 1 the lowest values (29; range 22-37).
Conclusion:
The EEG bispectrum, as well as the BIS appeared to be strongly related to the age of children at 1 MAC sevoflurane.
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