Optimizing Postoperative Analgesia in Total Knee Arthroplasty: A Randomized Controlled Trial on the Efficacy of Perineural Dexamethasone With iPACK and Adductor Canal Block.

OBJECTIVES

To assess the effect of perineural dexamethasone on analgesia duration and opioid consumption when used as an adjuvant to the iPACK (infiltration between the popliteal artery and capsule of the knee) block and adductor canal block in patients undergoing total knee arthroplasty.

METHODS

In this double-blind, randomized controlled trial, 60 patients aged 65 years or older undergoing total knee arthroplasty under spinal anesthesia were assigned to one of 2 groups. The control group received iPACK and adductor canal block with 0.2% ropivacaine alone, while the Dexamethasone group received the same blocks with the addition of perineural dexamethasone. The primary outcome was time to first opioid rescue analgesia. Secondary outcomes included total opioid consumption over 48 hours, postoperative pain scores at defined time points, quadriceps muscle strength, and adverse effects, including neurological complications and hyperglycemia.

RESULTS

Patients receiving dexamethasone experienced a significantly longer duration of analgesia (15.9±1.2 h vs. 8.8±1.6 h), lower total opioid consumption over 48 hours (1.2±1.3 mg vs. 2.3±1.4 mg morphine equivalents), and fewer patients required opioids (20% vs. 50%). Pain scores were significantly lower at 8 and 12 hours postoperatively. No differences were observed in motor function or adverse event rates.

DISCUSSION: Perineural dexamethasone enhanced the duration and quality of postoperative analgesia without compromising motor function. Its inclusion in regional analgesia protocols for total knee arthroplasty may contribute to improved recovery and reduced opioid use.