Monitoring sedation in the critically ill child.

Sedation is an essential part of the management of the critically ill child, and its monitoring must be individualised and continuous in order to adjust drug doses according to the clinical state. There is no ideal method for evaluating sedation in the critically ill child. Haemodynamic variables have not been found to be useful. Clinical scales are useful when sedation is moderate, but are limited by their subjective nature, the use of stimuli, and the impossibility of evaluating profoundly sedated patients or those receiving neuromuscular blocking drugs; in addition, many of these scales have not been evaluated in children. The COMFORT scale is the most appropriate, as it was designed and validated for critically ill children requiring mechanical ventilation. Electroencephalography-derived methods permit continuous monitoring, provide an early indication of changes in the level of sedation, and facilitate a rapid adjustment of medication. However, these methods were designed and validated for patients under anaesthesia and their results cannot be fully extrapolated to the critically ill patient; in addition, some of them have not been validated in small children and there is still little experience in critically ill children. The main indications for the use of these methods are in patients with deep sedation and/or neuromuscular blockade. The bispectral index is the most widely used method at the present time. Analysis and comparison of the efficacy of the different methods for evaluating sedation in the critically ill child is required.