Systemic Lidocaine Versus Ultrasound-guided Adductor Canal Block for Patients Undergoing Total Knee Arthroplasty

Patients scheduled to have total knee arthroplasty will typically receive a single shot adductor canal block to serve as the primary anesthetic and as part of a multi-modal post-operative analgesic plan. The use of adductor canal block is still limited to where trained anesthesiologists in regional anesthesia are available. There are other nonopioid analgesic adjuncts, such as Lidocaine, which is is widely available and is a very commonly used local anesthetic. A major advantage of lidocaine is that it is not associated with a significant side effect profile. Intravenous lidocaine which can be administered during surgery and/or after surgery has demonstrated anti-inflammatory effects and can significantly decrease the reliance on opioid use for adequate pain management in abdominal and spine surgeries. The addition of systemic lidocaine infusion as part of a multimodal analgesia strategy to minimize opioid related side effects might prove to be a useful combination for clinicians where adductor canal blocks are not a viable option. However, the level of evidence comparing the efficacy of intravenous lidocaine versus adductor canal block to reduce postoperative opioid consumption in patients undergoing TKA is limited. We hypothesized that there will be no meaningful clinical difference between systemic lidocaine and ultrasound-guided adductor canal block in the 24-hour postoperative analgesia period.

Inclusion criteria

• ASA PS 1-3 patients undergoing primary, unilateral total knee arthroplasty

Exclusion criteria

• ASA PS classification of 4 or greater
• Pre-existing neuropathy
• Coagulopathy
• Chronic opioid consumption (>3 months)
• Infection at the site
• Known allergy to study medications (lidocaine)
• High grade atrioventricular block (cardiac conduction system impairment)
• A history of CVA/TIA
• Currently using lidocaine patches
• Known liver disease