Unfortunately, this experience actually happens to patients, and it's one anesthesiologist always hope to avoid. Patient safety is always the primary concern for any anesthesiologist, but the patient experience isn't far behind. Awareness and recall can be traumatic for patients and lead to a suboptimal experience. Conventional cardiac and pulmonary measures are not completely reliable for ascertaining the level of hypnosis in patients undergoing general anesthesia, and the effects of general anesthesia on the brain are not yet fully understood.
However, advances in monitoring have been gamechangers for assessing patient depth of anesthesia.
Advanced depth of anesthesia monitoring assesses the effects of anesthetic drugs on the brain using electrode sensors applied to the patient’s forehead. This noninvasive system measures the degree of irregularity (depth of anesthesia) in electroencephalograph (EEG) signals, based on the general association between changes in EEG entropy and changes in the cerebral cortex. In adult patients, high entropy values (high irregularity in the signal) indicate that the patient is awake. Low entropy values (low irregularity in the signal) are associated with a likely lack of consciousness.1
Compared with standard clinical monitoring during general anesthesia, depth of anesthesia monitoring is associated with additional costs. Depth of anesthesia monitoring requires purchasing specialized equipment, including electrode-bearing sensors. Costs also include training for the relevant clinical staff in the use of depth of anesthesia-monitoring technology, as well as facility-related operational costs, such as updating protocols.
Depth of anesthesia monitoring can be helpful in guiding the clinician in administration and titration of anesthetic drugs, which may lead to an improvement in the quality of care and reduction in anesthesia costs and overall healthcare costs. In particular, EEG-based monitoring may be able to mitigate the occurrences of overdosing and underdosing.
