Validity of bispectral index monitoring during deep sedation in children with spastic cerebral palsy undergoing injection of botulinum toxin

Abstract

Background: This prospective study aimed to determine whether the bispectral index (BIS) is a valid objective tool for differentiating adequate from inadequate deep sedation in spontaneously breathing children with cerebral palsy (CP). Methods: Propofol was titrated to increase the level of sedation with a continuous infusion of remifentanil at a rate of 0.05 μg/kg/min while maintaining spontaneous ventilation in 22 children with spastic CP, aged 3–18 years. The depth of sedation was assessed using the University of Michigan Sedation Scale (UMSS) and the Modified Observer’s Assessment of Alertness and Sedation (MOAAS) scale. Receiver operating characteristic curve analysis was performed to determine the cutoff BIS values for deep sedation, defined as a UMSS score of 3–4 and a MOAAS score of 0–1. Results: The BIS values significantly changed with the increase in the level of sedation across both the UMSS and MOAAS scores (P < 0.001). The BIS values correlated with the UMSS (r = −0.795, P < 0.001) and MOAAS (r = 0.815, P < 0.001) scores. The cutoff BIS value to detect adequate deep sedation in children with CP was 61.5 (UMSS score: Sensitivity 0.860, specificity 0.814; MOAAS score: Sensitivity 0.794, specificity 0.811). Conclusions: The BIS value strongly correlates with the clinical sedation scales, such as the UMSS and MOAAS, during deep sedation in children with CP. Therefore, BIS monitoring can be used as a valid tool for assessing the level of propofol sedation in spontaneously breathing children with CP undergoing a botulinum toxin injection.