Fig. 3.
Effect of ketamine injection on electroencephalogram burst suppression ratio. (A and B) Representative electroencephalographic (EEG) traces (upper) and power spectrogram (lower) during the transition phase from the last isoflurane (Iso)-only sample up to the second Iso-after-injection sample for saline- (A) and ketamine-treated (B) animals. The EEG traces and spectrograms show four different phases divided by the vertical dotted lines. Color bar indicates normalized power in log scale in decibel (dB). (C) Rats treated with ketamine showed a significant 125% increase (*) in burst suppression ratio during Iso-after-injection sample 1 and a 107% increase (*) during Iso-after-injection sample 2 when compared to the last Iso-only sample in the ketamine group (red data points). In addition, ketamine-treated animals showed a significant enhancement in burst suppression ratio compared to saline-treated animals (red vs. blue data points). Graph shows data as burst suppression ratio in percent ± SD.