Buprenorphine versus dexamethasone as perineural adjuvants in femoral and adductor canal nerve blocks for total knee arthroplasty: a randomized, non-inferiority clinical trial.

Background: Optimal control of acute postoperative pain and prevention of chronic persistent pain in total knee arthroplasty (TKA) remain a challenge.

Methods: A randomized, non-inferiority clinical trial (385 patients) evaluated every hour immediate postoperative pain during 24 h, using a verbal rating 11-point scale for patient self-reporting of pain (VRS11). All patients received subarachnoid anesthesia and were randomly allocated in four groups: single shots femoral (FNB) or adductor canal blocks (ACB), both with dexamethasone (dex) and buprenorphine (bup).

Postoperative analgesia for elective total knee arthroplasty under subarachnoid anesthesia with opioids: comparison between epidural, femoral block and adductor canal block techniques (with and without perineural adjuvants). A prospective, randomized, clinical trial.

Background: Optimal control of acute postoperative pain and prevention of chronic persistent pain in total knee arthroplasty (TKA) remain a challenge. The main hypothesis was that nerve blocks improve postoperative analgesia especially if perineural adjuvants are added.

Methods: Immediate postoperative pain (24 hours) was evaluated every hour in 639 patients using a verbal rating 11-point scale for patient self-reporting of pain (VRS-11).