That's what attempts to be the scary tag line for the new movie "Awake" that may serve to put the problem of surgical awareness (or anesthesia awareness) into the national consciousness, rather than just an issue to be debated in the anesthesia community, or at this year's MEDICA exposition.

The phenomenon of being awake but unable to respond during surgery has been addressed by a variety of companies developing depth-of-anesthesia systems to measure the impact of anesthesia on the brain giving indications that the anesthesia is neither too great nor too little and, it is hoped, preventing an awake mind but sedated body.

The worldwide market for depth of anesthesia and sedation monitoring systems is led by Aspect Medical (Norwood, Massachusetts). Given the inherent difficulty in verifying the frequency of surgical awareness, Aspect has had an upheld battle in presenting its case for its bispectral index system system which it touts as serving to indicate, and thus avoid, surgical awareness, but it has made steady progress in that effort. The company has reported compound annual growth of 20% since 2002, reaching sales of $85 million last year.

Despite the number of other technologies in this arena, more are coming. And some new depth-of-anesthesia and sedation monitoring systems were introduced at MEDICA, thus offering potential competition in the sector.

Medical Device Management (Essex, UK) introduced the aepexPLUS depth-of-anesthesia monitoring system, a handheld, battery-operated device for monitoring of Auditory Evoked Potentials. The system measures the Middle Latency Auditory Evoked Potential, which responds to the depth of anesthesia by exhibiting reduced amplitude and increased latency, and is less affected by patient age than other components of the Auditory Evoked Response. The aepexPLUS can consequently measure the full depth of anesthesia vs. monitoring only the hypnotic state as do monitors that track EEG signals only.

While the device includes a display allowing the AEP waveform to be viewed directly, it also includes a wireless link allowing the signal to be viewed on multi-parameter monitors from Fukuda Denshi (Tokyo). The company is developing links to patient monitors manufactured by other leading suppliers.

Another handheld depth-of-anesthesia monitor, the IoC-View, was exhibited by Morpheus Medical (Barcelona). The battery-operated device employs 3-lead EEG measurements to derive an Index of Consciousness (IoC) ranging from 0 to 99.

The measurement technology is similar to that employed by Aspect, but the EEG analysis employs a different signal processing algorithm. An integral Bluetooth transmitter allows the waveform and computed IoC to be displayed on an auxiliary PDA.

A unique new feature now under development is Bluetooth EEG electrodes, which will eliminate the wires now used to interface the electrodes to the handheld analyzer, an important advance since the wires used with existing EEG-based anesthesia monitors can interfere with the surgeon's activities.