2013 Fiscal Year Final Research Report

A new approach to evaluate the anesthetic depth by evoked potential with sequential double stimulation.

Research Project

Project/Area Number	23590287
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Environmental physiology (including Physical medicine and Nutritional physiology)
Research Institution	University of Occupational and Environmental Health, Japan (2012-2013) Hamamatsu University (2011)
Principal Investigator	FUJIKI Nobuhiro 産業医科大学, 産業生態科学研究所, 教授 (80334928)
Project Period (FY)	2011 – 2013
Keywords	麻酔深度 / 体性感覚誘発電位 / 二連発刺激
Research Abstract	We observed a novel phenomenon that a ratio of two evoked potentials elicited by double sensory stimulation dynamically changes in response to the depth of anesthesia. Somatosensory evoked potential was recorded via a set of screw electrode on the skull in a male SD rat under the sevoflurane anesthesia. Two consecutive electrical stimulations were applied to the upper limb, and an amplitude ratio of the first response (R1) and second response (R2) were calculated (R2/R1). When the interstimulus interval is around 300 msec, R2/R1 dynamically decrease in response to the depth of anesthesia. On the other hand, if the interstimulus interval is longer than 300 msec, the decrease is smaller. These results suggest that the R2/R1 may be a novel indicator for evaluating the anesthetic depth.