The BIS monitor: a review and technology assessment.

In the administration of anesthesia, clinicians have traditionally relied on a variety of autonomic signs to assess the pharmacologic effects of anesthetic agents on the central nervous system. As any experienced clinician knows, these signs can be misleading and lead to overdosing or underdosing of anesthetic drugs. The development of a monitor to measure the bispectral index (BIS) provides anesthetists with the first clinically tested and US Food and Drug Administration-approved monitor to assess the effects of anesthesia on the cerebral cortex. This article reviews the development of the BIS monitor, compares the BIS monitor with other commonly used clinical monitors, assesses the cost-benefit from the use of this monitor, and explores some of the possible uses for this monitor outside of the operating suite.