Intraoperative neurophysiology monitoring in scoliosis surgery in children

OBJECTIVE: Intraoperative neurophysiology monitoring (INM) is thought to reduce the risk of postoperative neurological deficits in children undergoing scoliosis and spine deformity surgery. INM is being used increasingly despite conflicting opinions, varied results, non-standard alarm criteria and concern regarding cost effectiveness. In this paper we present our experience with INM in scoliosis and spine deformation surgery in children, propose alert criteria and preferred anaesthetics in clinical practice. METHODS: We retrospectively analysed our experience with INM in 56 children who had 61 scoliosis and spine deformity surgeries. RESULTS: INM was successfully undertaken with transcranial electrical motor evoked potentials (TcMEP) and somatosensory evoked potentials. There were no injuries due to INM. Four children had 5 alerts during 4 surgeries. A postoperative deficit was seen in one child only. No new postoperative deficits were seen in any child who did not have an alert during INM. Total intravenous anaesthesia was better for INM compared to inhalational anaesthetics. CONCLUSIONS: INM is useful in scoliosis surgery; it is likely to mitigate the risk of new deficits following surgery. We recommend alert criteria for TcMEPs that include multiple facets – amplitude, stimulus paradigm, morphology. We recommend propofol and remifentanil, in preference to sevoflurane and remifentanil for anaesthesia during INM. SIGNIFICANCE: Our study adds to the literature supporting the role of INM in scoliosis surgery in children. We provide guidelines for alarm criteria in clinical practice and recommend the use of total intravenous anaesthesia as the preferred anaesthetic option.