Propofol’s EEG Fast Activity is Dose-Dependent

Introduction: For patients with a first-time suspected seizure, electroencephalograms (EEG) are part of the initial evaluation. Most sedatives result in EEG artifact “fast activity” (FA), making the EEG difficult to read. During propofol-sedated EEGs, we noticed that FA would diminish when the propofol infusion rate was low. The purpose of this study is to investigate propofol dosing and its relationship to EEG FA artifact. Methods: This study involved retrospective chart reviews of a pediatric database for sedated EEG encounters in patients under 7 years of age. Data was collected from a total of 55 charts. Total doses of propofol (mg/kg/hr) were calculated for the first half and second half. The actual EEGs were reviewed by a pediatric neurologist study investigator, to classify the degree of FA as: none, mild, moderate, severe. We then examined whether total doses of propofol given during the EEG (mg/kg/hr) halves affected the severity of FA using ordinal logistic regression. Results: The results are summarized in Table 1, which shows that propofol doses (paired T-test, p<0.001) and EEG FA (Bowker’s test of symmetry, p=0.002) were higher in the first half compared to the second half. Figure 1 graphs each data point independently, which shows via linear and ordinal logistic regression a positive relationship between propofol dosing and FA severity (p=0.0014, OR=1.20, 95% CI=1.08-1.34, respectively). Results: The results are summarized in Table 1, which shows that propofol doses (paired T-test, p<0.001) and EEG FA (Bowker’s test of symmetry, p=0.002) were higher in the first half compared to the second half. Figure 1 graphs each data point independently, which shows via linear and ordinal logistic regression a positive relationship between propofol dosing and FA severity (p=0.0014, OR=1.20, 95% CI=1.08-1.34, respectively).