Background and aims Intraperative neurophysiological monitoring (IONM) is the use of electrophysiological methods to monitor the integrity of neural structures during surgery. Changes in IONM signals can predict intraoperative damage to the nervous system, serving as guidance to reduce permanent neurological damage in multilevel instrumentation scoliosis surgery in children. Certain anaesthetics, such as dexmedetomidine and clonidine, interfere with motor evoked potentials, preventing them from being used in surgeries with IONM. the use of systemic multimodal analgesia with magnesium sulfate, ketamine and lidocaine is discussed, aiming to reduce the intraoperative opioid use and the postoperative opioid requirement.

Methods Four consecutive pediatric patients aged 8 years or older who underwent scoliosis surgery with IOM were reviewed. a multimodal analgesic protocol consisting in magnesium sulfate 30 mg/kg, ketamine 0.5 mg/kg and lidocaine 1 mg/kg + postoperative perfusion was administered, alongside a remifentanil and propofol perfusion. the outcomes included intraoperative remifentanil requirements and postoperative opioid requirements.

Results A decrease of intraoperative remifentanil requirements was observed in all four patients. Two of them had no opioid requirements in the first 48 hours after surgery, another one required a single 3 milligram morphine dose in the first 24 hours. One patient required a morphine perfusion in the first 48 hours.

Conclusions Implementation of a multimodal analgesia protocol reduced opioid use both during surgery and after multilevel instrumentation scoliosis surgery in children, reducing the risk and secondary effects associated with opioid administration.