Multimodal perineural analgesia with combined bupivacaine-clonidine-buprenorphine-dexamethasone: safe in vivo and chemically compatible in solution.

Objectives: The use of adjuvants in regional anesthesia has increased. However, there are knowledge gaps pertaining to 1) in vivo local tissue effects of these adjuvants; and 2) chemical compatibility and solubility of these drugs in solution with each other and with local anesthetics. This study addresses these gaps in knowledge.