Dexamethasone as an adjuvant to erector spinae plane block is associated with improved neuromonitoring parameters and analgesia in pediatric spine surgery

BACKGROUND CONTEXT: Posterior spinal fusion for idiopathic scoliosis in children and adolescents is associated with severe postoperative pain and high opioid requirements. The erector spinae plane block (ESPB) provides effective analgesia, but its duration is limited. Dexamethasone prolongs peripheral nerve blocks in adults; however, its effects on analgesia and neurophysiological parameters in pediatric spine surgery remain unclear. PURPOSE: To evaluate whether dexamethasone administered within the fascial plane as an adjuvant to ESPB is associated with prolonged analgesia, reduced opioid consumption, and changes in motor neurophysiological parameters in pediatric scoliosis surgery. STUDY DESIGN/SETTING: Prospective, randomized, double-blind, controlled clinical trial conducted at a tertiary university hospital. PATIENT SAMPLE: Sixty children and adolescents aged 10 to 18 years with Lenke type 3 scoliosis undergoing posterior spinal fusion were randomized to receive ESPB with ropivacaine 0.2% plus dexamethasone (0.1 mg/kg; DEX group, n=30) or ropivacaine 0.2% alone (NO DEX group, n=30). OUTCOME MEASURES: Primary outcome was time to first rescue opioid analgesia within 48 hours postoperatively. Secondary outcomes included total opioid consumption, postoperative pain scores (Numerical Rating Scale, NRS), perioperative blood glucose levels, neurological complications, intraoperative motor evoked potentials (MEPs), and postoperative electroneurography (ENG) parameters. METHODS: Bilateral ultrasound-guided ESPBs were performed at T4 and T10 after anesthesia induction. Neuromonitoring included intraoperative transcranial electrical stimulation-elicited MEPs and postoperative transcranial magnetic stimulation-elicited MEPs, as well as postoperative motor ENG of the peroneal nerves. Pain scores and opioid consumption were recorded by blinded assessors. Appropriate parametric and nonparametric tests, including repeated-measures analyses, were applied. RESULTS: Time to first opioid administration was longer in the DEX group than in the NO DEX group (13.0±2.1 hour vs 5.2±1.6 hour; p