Dexamethasone vs. Dexmedetomidine as Adjuvants to Erector Spinae Plane Block in Total Knee Arthroplasty: A Randomized Double-Blind Controlled Trial.

Study Summary

90 patients undergoing elective primary total knee arthroplasty (TKA) were randomized to receive erector spinae plane block (ESPB) with ropivacaine alone, ropivacaine plus 4 mg dexamethasone, or ropivacaine plus 50 µg dexmedetomidine. The primary outcome was time to first rescue opioid requirement. Secondary outcomes included total 48-hour opioid consumption, Numerical Rating Scale (NRS) pain scores, neurological complications, and adverse events. Outcomes were assessed for up to 48 hours postoperatively. Overall, the results revealed that both dexamethasone and dexmedetomidine significantly prolonged the time to first opioid requirement compared with ropivacaine alone, but dexamethasone also significantly reduced total opioid consumption and provided better early pain control than dexmedetomidine. These findings suggest that dexamethasone may be the more effective perineural adjuvant for lumbar ESPB following TKA.