Effects of midazolam and lidocaine on spectral properties of the EEG in full-term neonates with stroke

Assessment of the neonatal EEG may be hampered by drug-specific changes in electrocortical activity. To quantify effects of a loading dose of midazolam and lidocaine on the EEG frequency spectrum of full-term neonates with perinatal arterial ischemic stroke (PAIS), 11 full-term infants underwent multi-channel amplitude-integrated EEG (aEEG) and EEG recordings. During recording, midazolam and/or lidocaine were administered as anti-epileptic drug. Retrospectively, we performed spectral analysis on 4-h EEG segments around the loading dose. The frequency spectrum was divided in delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz) and beta (13-30 Hz) bands. Midazolam induced immediate suppression of the aEEG background pattern for 30-60 mm. Spectral EEG analysis showed decreased total and absolute frequency band powers. Relative delta power decreased, theta power increased while alpha and beta powers remained constant. Lidocaine induced no aEEG background pattern suppression. Total and absolute EEG band powers were unchanged. Relative delta power decreased, theta and alpha power increased and beta power remained constant. Effects of lidocaine were more pronounced in the stroke-affected hemisphere. In conclusions, both drugs induced a shift from low to higher frequency electrocortical activity. Additionally, midazolam reduced total EEG power. These spectral changes differ from those seen in adult studies.