<prompt> Which of the following technique is used to evaluate the intraoperative awareness of an individual during anaesthesia?Cerebral pulse oximetryEnd tidal C02Bispectral indexColour Doppler  <response>: Bispectral index BIS monitor attempts to measure the effects of anesthesia on a patients level of consciousness by algorithmically processing the patients EEG and conveing it to a single number, which probably represents the patients state of awareness. BIS values range from 0 to 100. BIS number 60: Patient unable to respond to verbal commands BIS number 70: Corresponds to a higher likelihood of awareness BIS number of 90- 100: Awake BIS numbers between 45 and 60 are, in general, considered to be optimal for a relatively healthy patient undergoing a routine general anesthetic and surgery. Ref:Clinical Anesthesiology By G. Edward Morgan, 4th Edition, Chapter 6 