Opioid-free analgesia following total knee arthroplasty - A multimodal approach using continuous lumbar plexus (psoas compartment) block, acetaminophen, and ketorolac

Background and Objectives: Traditionally, postoperative analgesia following total knee arthroplasty (TKA) has been provided by neuraxial or peripheral regional techniques with supplemental administration of opioids. We report an alternative method of postoperative pain management for patients undergoing TKA in whom the use of systemic or neuraxial opioids may result in significant side effects. Case Report: A 74-year-old woman with a history of protracted nausea and vomiting after systemic and neuraxial opioid administration presented for left total knee arthroplasty. A spinal anesthetic with postoperative continuous lumbar plexus (psoas) analgesia was planned. A quadriceps motor response was elicited and a 20-gauge catheter was advanced through an 18-gauge insulated Tuohy needle into the psoas sheath. After 30 mL of bupivacaine 0.5 % with 100 mug clonidine was administered through the psoas catheter, a spinal anesthetic (2 mL 0.5 % bupivacaine at the L2-3 interspace) was performed. A continuous psoas infusion of 0.2 % bupivacaine with 2 mug/mL clonidine at 8 mL/h was initiated in the recovery room. The psoas infusion was subsequently changed to 0.2 % bupivacaine without clonidine and the rate increased to 10 mL/h. Supplemental analgesia with oral acetaminophen 1 g every 4 to 6 hours alternating with intravenous ketorolac 15 mg every 6 hours provided satisfactory analgesia, with visual analog scale (VAS) scores of 0 to 2 at rest and 3 to 4 with movement. The psoas catheter was removed 48 hours postoperatively because of prolongation of the prothrombin time. VAS scores remained 0 to 3 throughout the remainder of her hospitalization. Conclusion: A multimodal approach consisting of continuous lumbar plexus (psoas) block and nonopioid analgesics successfully provided postoperative pain relief in our patient and facilitated her physical rehabilitation after total knee arthroplasty.