Assessment of the Level of Sedation in Children After Cardiac Surgery

Background There is no reference method for the evaluation of the level of sedation in children after cardiac surgery. The utility of the bispectral index and middle latency auditory evoked potentials has not been evaluated. Methods The bispectral index, middle latency auditory evoked potentials, Ramsay scale, and COMFORT scale were used for assessment of the level of sedation in critically ill children after cardiac surgery and other surgical procedures. The measurements with these four methods were recorded simultaneously once a day for five days. The level of sedation was categorized in two levels, moderate or deep, according to the values obtained from each method. Correlations and agreements among the methods and the best bispectral index and middle latency auditory evoked potential values that discriminated between the two levels of sedation were calculated. Results Thirty-two children after cardiac surgery were included in the study, together with eighteen children after other surgical procedures who formed the control group. In each group, the correlation and agreement between the four methods varied between moderate and good. In the cardiac surgery patients, when the level of sedation was determined by the Ramsay scale, the best values of bispectral index and middle latency auditory evoked potentials that discriminated between the two levels of sedation were 63.5 and 37.5, respectively, and these values predicted the level of sedation correctly in 84.4% of the patients with each method. Conclusions Bispectral index and middle latency auditory evoked potentials could be useful to assess the level of sedation in children after cardiac surgery.