The purpose of this research study is to compare two different combinations of anesthetic medications to see which works the best in providing the longest lasting pain relief for total knee arthroplasty surgery. The drugs being used are liposomal bupivacaine compared to a combination of bupivacaine, clonidine, epinephrine, buprenorphine, and dexamethasone. Pain scores will be collected at different intervals during study participation.
18-80 years of age
Receiving primary total knee arthroplasty
Patients receiving a spinal anesthetic with ropivacaine and fentanyl
American Society of Anesthesiology (ASA) category 1 to 3
Revision of Total Knee Arthroplasty
Opioid use in the prior 6 months > 40 mg oxycodone equivalents per day or long-acting opioids as determined by the Prescription Drug Monitoring Program (PDMP)
Patients planned to receive general anesthesia
Patients planned to receive a spinal other than ropivacaine