Monitoring of auditory evoked potentials (AEP) in patients during general anaesthesia is commonly used to ensure a sufficient hypnotic level during surgery. The amplitude of AEP (AEPa) has in clinical settings been found to correlate to pain. The aim of the study was to test, if AEPa could detect increasing experimental pain stimulations in healthy volunteers. Electric nerve stimulation, cold and heat pain were used as pain models.

During the AEP monitoring, healthy volunteers were exposed to experimental pain. At study day 1: Firstly, single electric nerve stimulation and repetitive electric nerve stimulations causing temporal pain summation. The stimulations were given at 50, 75 and 100% of the thresholds for pain tolerance and temporal pain summation. Secondly, the volunteers were exposed to cold pain by use of two different Cold Pressor Tests (CPT) with water temperatures at 8 and 1 Celsius. All measurements were repeated after an hour to test reproducibility.

At study day 2: Brief Thermal Stimulation were used with two different temperatures and duration.

Inclusion Criteria:

• Healthy
• Age 20 - 40 years old

healthy volunteers