Use of continuous bispectral EEG monitoring to assess depth of sedation inICU patients

Monitoring the depth of sedation in patients under intensive care is diffic ult. Clinical assessment by the different scoring systems produces insuffic ient information, especially once deeply sedated patients become unresponsi ve to any external stimulation. Recently the bispectral index (BIS), the re sult of computerized bispectral electroencephalographic monitoring, was fou nd to be the best predictor of depth of anaesthesia during surgical interve ntion. This report concerns BIS monitoring in 18 randomly selected, deeply sedated, surgical patients in the intensive care unit, who were unresponsiv e to standard clinical stimulation (Ramsay sedation score). A wide range of BIS was observed, with 15 of the patients having a BIS below 60, indicatin g a state of deep sedation (or possibly oversedation). Therefore, further s tudies using BIS monitoring in patients under intensive care are needed to determine if this method can guide sedation and prevent oversedation in thi s context and, most importantly, to analyse its final cost - benefit ratio.