Related Experiment Video
Updated: Aug 6, 2026
Infant Auditory Processing and Event-related Brain Oscillations
Published on: July 1, 2015
[Detection of intraoperative awareness via auditory evoked potentials in an infant]
M S Feuerecker1, M Daunderer, N-B Pape
1Klinik für Anästhesiologie, Ludwig-Maximilians-Universität, Marchioninistr. 15, 81377 München.
Insights
Intraoperative awareness occurs in children, similar to adults. Midlatency auditory evoked potentials (MLAEPs) show promise for detecting awareness during pediatric anesthesia.
Area of Science:
- Anesthesiology
- Neuroscience
- Pediatric Medicine
Background:
- Intraoperative awareness, though rare, affects both adult and pediatric anesthesia patients (0.8% in pediatrics).
- Neurophysiological monitoring, such as auditory evoked potentials, may help prevent intraoperative awareness.
Observation:
- A case study involving a 2-year-old boy undergoing balanced anesthesia with sevoflurane and alfentanil.
- Continuous recording of midlatency auditory evoked potentials (MLAEPs) before, during, and after surgery.
- Unintentional sevoflurane withdrawal led to coughing and movement, initially attributed to inadequate analgesia.
Findings:
- MLAEPs demonstrated inadequate suppression of auditory processing during the anesthetic event, with latencies similar to the awake state.
- Post-anesthetic restoration of sevoflurane resulted in near-complete MLAEP suppression, indicating adequate anesthetic depth.
- This case highlights MLAEPs' potential to detect intraoperative awareness in pediatric patients.
Implications:
- MLAEPs may serve as a valuable tool for monitoring anesthetic depth and detecting awareness in pediatric patients.
- Further research is needed to establish the validity and reproducibility of MLAEPs in children.
- Improved neurophysiological monitoring could enhance patient safety during pediatric surgery.
Abstract:
Intraoperative wakefulness is not only limited to adults and can also be found at a similar percentage (0.8%) in paediatric anaesthesia. For prevention of awareness neurophysiologic methods like auditory evoked potentials might be helpful. We report a case of a 2-year-old boy receiving balanced anaesthesia with sevoflurane and alfentanil. Midlatency auditory evoked potentials (MLAEPs) were recorded continuously before, during and after the surgical procedure. During the surgical procedure sevoflurane was withdrawn unintentionally. After a short period of time the boy started coughing and moved his legs, which was interpreted as insufficient analgesia. Several boli of alfentanil did not lead to the expected clinical effect on the depth of anaesthesia. After a recheck of the anaesthetic ventilator the error was determined and delivery of the volatile anaesthetic restored. The postoperative evaluation of the MLAEPs revealed the inadequate suppression of auditory processing during this incident with latencies comparable to the awake state. After reapplication of sevoflurane the MLAEPs were almost completely suppressed demonstrating adequate anesthetic depth. Exemplarily this case suggests that MLAEPs could be used to detect intraoperative awareness also in paediatric anaesthesia. Investigations to prove the validity and reproducibility of MLAEPs in children will be necessary.
