Lumbosacral spinal cord somatosensory evoked potentials for quantification of nociception in horses

摘要: Summary Reasons for performing study: There is a need objective evaluation and quantification of the efficacy analgesic drugs techniques in horses. Objectives: To determine whether lumbosacral spinal cord somatosensory evoked potentials (SSEP) can be useful reliable tool to assess nociception equines. Methods: SSEPs electromyograms (EMG) from epaxial muscles were recorded simultaneously, following electrical stimulation applied distal hindlimb lightly anaesthetised Shetland ponies (n = 7). In order validate model, effect increasing stimulus intensity was documented conduction velocities (CV) stimulated nerves calculated. The epidurally methadone (0.4 mg/kg bwt) randomised, crossover design investigated. Results: Two distinct complexes (N1P1 N2P2) identified SSEP waveform. Based on their latency velocity depressant methadone, N2P2 ascribed nociceptive Aδ-afferent stimulation. N1P1 originated non-nociceptive Aβ-afferent not influenced by methadone. Conclusions potential relevance: Aδ component SSEP, complex, presented as valid quantitative parameter processing horse. Validation equine model enables effects new analgesics/analgesic quantified analgesia protocols caudal epidural equidae improved.