EEG to Monitor Propofol Anesthetic Depth in Infants and Toddlers

Sevoflurane inhalation and propofol intravenous anesthesia are the mainstays of delivering general anesthesia in children. Propofol anesthesia in children is gaining popularity due to fewer respiratory complications, less post-operative nausea vomiting and emergence delirium, compared to sevoflurane. However, unlike sevoflurane, the pharmacodynamics of propofol is less studied in infants and toddlers, particularly the biomarker for propofol brain effect site concentration (Ce), indicative of anesthetic depth. The lack of a real-time biomarker often results in over- or under-dosing of propofol in clinical practice. The goal of this study is to utilize electroencephalography (EEG) as the biomarker of propofol effect site concentration and clinical anesthetic depth, thereby improving the safety and efficacy of propofol anesthesia in this population. In infants and toddlers receiving propofol anesthesia, EEG will be recorded while the patient undergoes three stimuli used to assess anesthetic depth (placement of oral pacifier, electrical stimulation, and laryngoscopy). The EEG index (spectral edge frequency-SEF95) where 50% of patients (ED50) do not respond to each of the three stimuli will be determined as the biomarker of propofol clinical anesthetic depth. In the same cohort, the regression between EEG SEF95 and plasma propofol levels will be determined to assess relationship between EEG SEF95 and propofol Ce.