Anaesthesia Made to Measure

Narcotrend UK Distributor Contact Information:

Gwenagen Ltd  30-38 Dock St Suite 24 Leeds LS10 1JF 

Contact: Gwen Merkelbach

T: 0113 887 4171 

M: 07812 080 496



Assessing the depth of hypnosis during TIVA and inhaled anaesthesia

Narcotrend - Depth of Anaesthesia Monitor

now also in the United Kingdom and Ireland:

Gwenagen Ltd has recently been appointed UK Distributor for Narcotrend Compact M Monitor.


Latest News: follow these links for the supporting documentation on the cost-effectiveness and QALY scores provided by NIHR and NICE.

Points to highlight  about the latest version (new software version and hardware upgrade of the amplifier) that may interest you:

  • Age-related algorithm (validated for all ages incl Neonates)

  • Many different trends displayed incl Density Spectral array

  • Flexible electrode placement

  • Low cost per patient with standard available electrodes

  • Index shows no correlation with EMG during anaesthesia phases (Panousis 2007)

  • Faster integration time (validated for Xenon)

  • 2 hour battery life and lightweight make mobile use easy


This method (Narcotrend®) allows for adjusting the dosages of anaesthetics to the patients' age, gender and general physical condition. The Narcotrend (MonitorTechnik, Bad Bramstedt, Germany) is an EEG monitor designed to measure the depth of anaesthesia.

It has been developed at the University Medical School of Hannover, Germany, has been commercially available for over 10 years and has meanwhile received US Food and Drug Administration approval and is included in the NICE guidelines.


The Narcotrend algorithm is based on pattern recognition of the raw electroencephalogram (EEG) and classifies the EEG traces into different stages from A (awake) to F (increasing burst suppression down to electrical silence).

The raw EEG signal can be recorded by standard electrocardiogram electrodes for single- and double-channel registration.

The Narcotrend monitor provides a vast amount of information: the actual Narcotrend stage and index, the trend ('cerebrogram'), the raw EEG signal and a power spectrum and several derived EEG parameters. 


We have the very latest version monitor available for evaluations and demonstrations and welcome a call or email.

Multi center analysis 4630 patients

Propofol dosage during Steady State of anaesthesia

(range and median)

  • Huge individual deviation of Propofol demand

  • Median dose clearly lower than recommendations of the expertise literature

For more information please visit


For specific  literature please contact us or visit:

© 2013 by Gwenagen Ltd All rights reserved.

Call Leeds Office

T: 0113 887 4171


M: 07812 080 496