Intraoperative Detection of Awareness

BY COSIMO ARNESANO

BME 240-Spring 2009

introduction

definitions

intraoperative awareness

monitoring techniques

bispectral index (BIS)

auditory evoked potentials

other techniques

conclusions

references

bme 240

What is General Anesthesia?

General anesthesia is a reversible state characterized by unconsciousness, analgesia, muscle relaxation, and depression of reflexes which is achieved by the administration of chemical agents. As the intensity of surgical stimulation varies during a surgical procedure, so does the requirement of anesthetic agents. The organ system effects of anesthetic drugs may limit the amount that can be given safely. This would, at occasions, create a critical imbalance between anesthetic requirement and anesthetic drug administration resulting in varying depth of anesthesia and, ultimately, in awareness. Unintended intraoperative awareness occurs when a patient can recall some or all of the events happening during a surgical procedure.