The aepEX system dynamically measures the balance between hypnosis, analgesia and surgical stimulation using Auditory Evoked Potentials (AEPs) providing the anaesthesia community with the first fast, accurate and compact depth of anaesthesia monitoring system utilising a proven technology.

aepEX combines years of proven clinical data with 21st Century technology enabling anaesthesia professionals to prevent surgical awareness, reduce the amount of drug used during surgery, reduce recovery times and increase the overall safety of anaesthesia.

Developed over a ten year period by Professor Gavin Kenny and Dr Harris Mantaridis at Glasgow University, numerous clinical studies have shown that the system is able to provide an accurate guide to the patient’s level of consciousness. The clinician is thus allowed to decrease the levels of drug
delivered without compromising the maintenance of adequate levels of anaesthesia, and reduce the risks of arousal during surgery.

aepEX utilises state-of-the-art electronic technology to ensure both speed and accuracy in a compact and ergonomic format, making it easy to use and saving valuable space in the Operating Room environment.

aepEX index, method of extraction and calculation

The aepEX monitor generates repeated auditory stimulation via the
earphones at a nominal frequency of 7 Hz.

Following each auditory stimulation for a period of 144 milli-seconds
the aepEX unit monitors the patient’s EEG signal via three sensors.

During the 144 milli-second period following the stimulation the
EEG signal includes the Brainstem Auditory Evoked Potential (BAEP)
and the Middle Latency Auditory Evoked Potential (MLAEP) which
are the sensory system’s and the brain’s response to the auditory
stimulation.

The Brainstem Auditory Evoked Potential originates in the VIIIth
cranial nerve and the brainstem auditory structures while the Middle
Latency Auditory Evoked Potentials originate in upper brainstem
and auditory cortex.

It is generally accepted that the Middle Latency Auditory Evoked Potential responds to the depth of anaesthesia by exhibiting reduced amplitude and increased latency proportional to the depth of anaesthesia. The Middle Latency is also less affected by age than other parts of the Auditory Evoked Response reducing the effect that age may have on the resulting aepEX index.

The sensors are configured as a near and far pair; these signals are combined to reduce noise. The ground electrode is placed on the centreline of the forehead
and the active electrode is also placed on the forehead to the side of the ground electrode. The reference electrode is placed over the mastoid behind the ear on
the same side of the head as the active electrode.

The processor extracts from the raw EEG signal the Auditory Evoked Potential (AEP). The extraction is achieved by averaging the previous 256 EEG waveforms achieving a rolling average AEP waveform each of which
is built up from 256 samples. The rolling average is updated 7 times per second following each stimulation. The software determines the characteristics of the
waveform, which is then expressed as an index between 0 and 100 (0 representing no brain activity and 100 representing wide awake).

EXpect more with aepEX

Features include;
OR or ICU mode
Advanced signal recognition system
Real Time download to monitors or computer systems
aepEX Trend Data post-operative download facility
Monitor modules for system integration
Fully illuminated screen
High-impact carry case

aepEX System
aepEX unit and power supply
Headphones and cable
Sensor cable and three sets of sensors
Three sets of ear gels
Bag of six Sensor Preps

Disposables
AEP 1109 Sensors
Box of 50 sets, each set with three sensors (packed individually) and
sixty Sensor Preps
AEP 1108 Ear gels
Box of 60 pairs (20 each of small, medium and large), each pair individually packed
AEP 1121 Ear gels Pack of 50 pairs, small
AEP 1122 Ear gels Pack of 50 pairs, medium
AEP 1123 Ear gels Pack of 50 pairs, large

Accessories
AEP 1129 (UK) Power supply
AEP 1104 Headphones and cable
AEP 0026 Headphone cable only
AEP 0027 Headphones only (set of two)
AEP 1112 Sensor cable
AEP 1117 aepEX simulator
AEP 0128 Bag of 60 Sensor Preps
AEP 1120 Battery pack
AEP 1118 PC data logger interface
AEP 1119 PC data logger interface USB adaptor
AEP 1125 Trend download cable
AEP XXXX Instructions for use (specify language)

Patent Applications Based on WO98/10701 including US PCT 09/973568 GB 97/0245
Further Applications Pending

Manufactured by:
Medical Device Management Ltd
57 The Lakes Industrial Park
Braintree
Essex
CM7 3RU
United Kingdom
Telephone +44 (0)1376 342303
Fax +44 (0)1376 342304
Email info@medicaldevicemanagement.com