Entropy and bispectral index in brain-dead organ donors

Excerpt

Sir: We read with interest the paper by Wennervirta et al. [1] evaluating the usefulness of entropy and bispectral index (BIS) in brain-dead patients during organ retrieval. The authors reported that both entropy and BIS showed non-zero values due to many artifacts, such as electrocauterization, 50-Hz artifact, handling of the donor, ballistocardiography, electromyography, and electrocardiography, and that BIS was more liable to artifacts than entropy. Consecutively, they concluded that neither of these indices could be used as diagnostic tools in the evaluation of brain death. In contrast, our group had previously investigated BIS in severely comatose patients, and we had demonstrated that BIS could be used as an useful assessment of brain death onset [2]. We would like to comment on these discrepancies between our study and that by Wennervirta et al. …