The Richmond agitation–sedation scale and bispectral index during dexmedetomidine sedation

Abstract

Introduction Patients require continuous reassessment of their pain and need for sedation. The routine use of standardized and validated sedation scales and monitors are needed. The bispectral index (BIS) uses a monitor of cortical suppression to maintain the optimal level of sedation and hypnosis. The Richmond agitation sedation scale (RASS) has high reliability and validity in ICU patients. We aimed to assess the correlation of the BIS with the RASS during dexmedetomidine sedation. Methods Eleven ventilated critically ill patients, aged 17–82 (50.09 ± 17.76) years, APACHE II score of 12.63 ± 3.90, SOFA score of 3.27 ± 1.73, were enrolled in the study. Patients received a loading dexmedetomidine infusion of 1 μg/kg over 10 min followed by a maintenance infusion of 0.5 μg/kg/hour for 8 hours. The efficacy of sedation was assessed using the RASS and BIS monitoring. The Wilcoxon test and Spearman's correlation analysis were used for statistical analysis. Results Significant correlations between RASS and BIS values were found in this study (Table 1). Table 1 RASS 1 RASS 2 RASS 3 RASS 4 RASS 5 RASS 6 RASS 7 RASS 8 BIS 1 r = 0.77, P = 0.005 BIS 2 r = 0.87, P = 0.0001 BIS 3 r = 0.84, P = 0.001 BIS 4 r = 0.84, P = 0.001 BIS 5 r = 0.94p, P = 0.0001 BIS 6 r = 0.85, P = 0.001 BIS 7 r = 0.92, P = 0.0001 BIS 8 r = 0.90, P = 0.0001 BIS, bispectral index; RASS, Richmond agitation sedation scale. Conclusion RASS levels significantly correlated with BIS values during dexmedetomidine sedation.