Continuous Adductor Canal Infusion vs. Single-injection Adductor Canal Block for Total Knee Arthroplasty

Multimodal analgesia (MMA) has been endorsed to improve postoperative analgesia and functional activity after surgery, and integrating regional analgesia to reduce the consumption of opioid has also been used in postoperative pain management. The investigator try to find a better combination of MMA for postoperative analgesia and functional recovery for patients receiving TKA in Taiwan, therefore the effect of single-injection and continuous infusion of peripheral nerve block is compared in patient undergoing unilateral TKA. The investigators hypothesize that continuous adductor canal infusion is as effective as single-injection adductor canal block for postoperative pain relief under intravenous PCA after TKA surgery. Based on that, the investigators conduct this prospective, randomized controlled trial to examine our hypothesis.

Inclusion CriteriaClinical diagnosis of knee osteoarthritisMust be aged between 20 to 90 years oldMust be scheduled for unilateral total knee arthroplasty surgeryMust agree to enroll into the clinical trial and have signed the written informed consentExclusion Criteria:American Society of Anesthesiologists physical status class IV-VElevated liver enzymes or liver failureRenal dysfunction (serum creatinine level ≥ 1.5 mg/dL)Cardiac failureOrgan transplantation recipientStrokeMajor neurological deficit with lower extremity muscle weaknessSensory and motor disorders in lower limbCoagulopathy or thrombocytopeniaPrevious drug dependencyPatients who used illicit drugs within six monthsChronic use of opioidsAllergy to local anesthetics and drug used in experimentInability to walk independentlyInability to comprehend pain assessmentRefusal for implanting a continuous peripheral nerve catheterRefusal for enrolling in study