How can the BIS monitoring reduce the anaesthetic use ?

bispectral index monitoring generates an index value  between zero (flat line EEG) and 100 (awake state) that  reflects the state of frontal EEG activity.

there is quasi-linear relationship between dose of GABA agonist and index value ; the recommended range for GA is between 40-60.

Now ; by basing anesthetic dosing on the BIS number , perhaps anesthetic drug overdose can by avoided .

BIS monitoring shows hybernation level. It does not show depth of anesthesia

The BIS may be useful to determine the dose of anesthetic to avoid the risk of intraoperative awareness in patients undergoing surgery at high risk of return of consciousness. In addition, guided anesthesia by bispectral index (BIS) improves the administration of anesthesia and recovery from anesthesia.

Bis monitoring is a very important element of monitoring tools used to provide safe and good  anesthesia for surgery. With BIS we are able to monitor CNS activity and to predict level of anesthesia, to ensure that our patient is not awake during intervention. Among that it can give us opportunity to adjust use of anesthetic drugs and give us a chance to decrease or reduce amount of used anesthetics. 

It ensures use  of exact amount of dose whichis required by the patient

By titrating drug doses according to depth of anesthesia.

BIS is used to measure the effects of anesthesia in the body.

BIS monitors are very important because they allow anesthesiologists and nurse anesthetists to monitor and control the depth of a patient’s anesthesia (and formulate the precise type and optimal dosage of anesthetic or sedative medication) in order to minimize the possibility of intraoperative awareness (waking up during surgery and recalling unpleasant experiences after the procedure). BIS monitors play a leading role in enabling today’s anesthetic doses to be predicated on patient cerebral cortical response and not simply determined by the anesthesiologist's 'best guess.'