The effect of anaesthesia on somatosensory evoked potential measurement in a rat model

Abstract

Somatosensory evoked potentials (SEPs) are widely used to study the functional integrity of ascending sensory pathways. For animal studies, SEPs provide a convenient method to quantitatively assess the functionality of the nervous system with low invasiveness. Even though they are frequently used in animal models, little attention is paid to the fact that SEPs are vulnerable to contamination from experimental factors such as anaesthetic delivery. In this study, the effect of isoflurane on SEP measurement was investigated in a rat model. The aim was to find out the adjustments for anaesthetic delivery optimizing the quality of the recordings. Two aspects were studied: the effect of isoflurane dosage on the SEP parameters and on the repeatability of the measurements. The SEP quality was found to be best when 1.5% isoflurane concentration was used. This dosage resulted in the best signal-to-noise ratio and equal repeatability of the measurements compared with the others. Our findings can help in refining the anaesthetic protocols related to SEP recordings in a rat model and, by improving the quality of the measurements, potentially reducing the number of subjects needed to carry out studies.

Characterization of transection spinal cord injuries by monitoring somatosensory evoked potentials and motor behavior

“…In addition, we performed two-way ANOVA [Injury × Day of Recovery] to investigate interactions between these two factors. All of the above statistical tests were also performed similarly on the BBB scores data (Sherman et al, 2010;Kortelainen et al, 2014;Kortelainen et al, 2016;Mir et al, 2010).…”

Separability of neural responses to standardised mechanical stimulation of limbs

“…Anaesthetic depth was maintained via isoflurane in oxygen delivered through the nose cone and additional intraperitoneal injections of the midazolam and hypnorm cocktail. During recordings of sensory signals maintenance doses of the cocktail were given so as to keep the Isoflurane level below 0.5% as Isoflurane has been shown to interfere with neural signal propagation at high doses 37 . Adequate anaesthetic depth was indicated by absence of withdrawal in response to a toe pinch, and the presence of a regular respiratory rhythm.…”

Neuroprotective Role of Hypothermia in Acute Spinal Cord Injury

“…The SSEP measurement is a non-invasive procedure and is performed routinely in clinical settings and in the research models of SCI. It provides objective assessments of the onset, severity, and progress of the injury, as well as the endogenous and therapeutic recovery post-SCI [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. The SSEP has extensively been used to assess stem cell replacement therapy [ 52 , 53 , 54 , 55 ] as well as plasticity and reorganization of neuropathways [ 31 , 56 ] post-SCI as well.…”