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Intermediate Technical IVT

bispectral index

Also written as: BIS — Bispectral Index

A processed EEG parameter scaled from 0 to 100 used to monitor the depth of sedation or hypnosis during anesthesia.

Full Definition

The bispectral index (BIS) is derived from a proprietary algorithm that analyses the electroencephalographic (EEG) activity captured by a frontal sensor and converts it to a dimensionless number. A BIS value of 100 represents full wakefulness; values of 40–60 are associated with general anesthesia; values below 40 may indicate excessively deep sedation. In dental anesthesiology, BIS monitoring helps clinicians avoid inadvertent deep anesthesia during office-based procedures. Editors should confirm that BIS is rendered in full capitals and that the device brand (e.g., Medtronic BIS™) is distinguished from the generic parameter name.

Usage

Usage note: BIS is a registered trademark of Medtronic in some contexts; confirm whether the generic or proprietary term is intended when editing clinical documents.

In Context

  • "Continuous bispectral index monitoring confirmed that the patient remained within the moderate sedation range throughout the extraction." — Clinical research article
  • "The protocol mandated a bispectral index of 70–85 for the anxiolysis cohort." — IRB-approved study protocol

Also known as

BIS monitoring EEG depth monitoring

Don't confuse with

Ramsay Sedation Scale Aldrete score

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