{'fraction_non_alphanumeric': 0.04638009049773756, 'fraction_numerical': 0.03676470588235294, 'mean_word_length': 4.7435064935064934, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Performance of the Cerebral State Index During Increasing Levels of Propofol Anesthesia: A Comparison with the Bispectral Index

BACKGROUND:The cerebral state monitor is a new device to measure depth of anesthesia. In this study we compared the cerebral state monitor with the bispectral index (BIS) monitor during propofol anesthesia. METHODS:Fifteen healthy patients received a continuous infusion of propofol (300 mL/h). The cerebral state index (CSI) and the BIS values were recorded until burst suppression ratio ≥60%. Baseline variability, prediction probability, and agreement analysis between indices were evaluated. Clinical markers of loss of consciousness were also assessed. RESULTS:Mean awake BIS and CSI values were 95.6 and 91.6, respectively (P = 0.01). BIS and CSI prediction probability values (mean ± sd) were estimated to be 0.87 ± 0.08 and 0.86 ± 0.08, respectively (NS). The CSI tended to stabilize at values of 60–40 when estimated propofol concentrations at the effect site increased from 5 to 8 &mgr;g/mL. The BIS stabilized at values of 40–20 when the propofol concentrations at the effect site increased from 7 to 10 &mgr;g/mL. The mean BIS-CSI difference was −7.4 with 95% limits of agreement of 22.2 and −36.9. The BIS and CSI correlation with the burst suppression ratio was −0.60 and −0.97, respectively (P < 0.01). Predicted BIS and CSI values for loss of eyelash reflex in 50% and 95% of the patients were different (P < 0.05). CONCLUSION:The overall performance of both monitors during propofol induction was similar. However, the different dynamic profiles of these monitors indicate that BIS may be a more useful index for evaluating intermediate anesthetic levels, whereas CSI may be better for evaluating deeper anesthetic levels.