Preemptive Co-infiltration of Dexamethasone Palmitate With Ropivacaine for Postoperative Pain in Major Spinal Surgery

The local infiltration solution in the dexamethasone palmitate emulsion(DXP) plus ropivacaine group will consist of ropivacaine and dexamethasone palmitate emulsion(DXP). For local infiltration, a total of 30mL solution will be prepared for each group, which will include 2mL of DXP(4mg per 1mL) added to 20.5 mL of saline and 7.5mL of 1% ropivacaine added to 15mL of saline for Group A . The surgeon will perform incision infiltration before the skin incision. A total of 10 mL of solution will be injected into each level. The study solution will be injected into the entire thickness of the planned incision site. The epidural space and intrathecal space will not be infiltrated.

The local infiltration solution in the ropivacaine alone group will consist of ropivacaine alone. For local infiltration, a total of 30mL solution will be prepared for each group, which will include 7.5mL of ropivacaine added to 22.5mL of saline for Group B . The surgeon will perform incision infiltration before the skin incision. A total of 10 mL of solution will be injected into each level. The study solution will be injected into the entire thickness of the planned incision site. The epidural space and intrathecal space will not be infiltrated.