Recommended Pain Management Regime for Bilateral Adductor Canal Blocks in Bilateral TKR
For patients undergoing bilateral total knee replacement (TKR), a multimodal pain management approach utilizing bilateral adductor canal blocks (ACB) is recommended as part of an effective analgesic strategy to optimize pain control while minimizing side effects and promoting early rehabilitation.
Primary Anesthetic and Analgesic Technique
- Bilateral adductor canal blocks should be performed as part of a multimodal analgesic approach for bilateral TKR, as peripheral nerve blocks provide effective postoperative analgesia while preserving quadriceps strength better than other regional techniques 1, 2
- The adductor canal block should be performed in the mid-thigh region (true ACB) rather than in the femoral triangle (FTB) for superior analgesia and better preservation of quadriceps strength 2
- General anesthesia combined with bilateral adductor canal blocks is recommended for the surgical procedure, or alternatively spinal anesthesia with local anesthetic plus spinal morphine 1
Multimodal Analgesic Protocol
- Scheduled administration of paracetamol (acetaminophen) should be included as a baseline analgesic 1
- Add conventional NSAIDs or COX-2 selective inhibitors unless contraindicated 1
- Supplement with intravenous strong opioids for breakthrough high-intensity pain, or weak opioids for moderate to low-intensity pain 1
- Implement cooling and compression techniques to the surgical site to reduce local inflammation and pain 1
Special Considerations for Bilateral TKR
- Anticipate potentially greater pain in the second operated knee when performing staged bilateral TKR, as evidence suggests enhanced pain sensitivity after the initial surgical injury 3
- Consider using higher concentrations or volumes of local anesthetic in the second knee's adductor canal block when performing staged procedures 3
- Monitor for increased analgesic requirements for the second knee and adjust the multimodal regimen accordingly 3
Optimization of Adductor Canal Block Technique
- Use ultrasound guidance to ensure accurate placement of local anesthetic in the adductor canal 2
- Consider adding a periarticular injection in combination with the adductor canal block for improved pain control, as this combination has shown better pain relief at 24 hours post-surgery 4
- For extended analgesia, consider continuous adductor canal catheter technique rather than single-shot injection, though more research is needed to definitively establish superiority 1
Avoiding Common Pitfalls
- Avoid performing the block too proximally in the femoral triangle as this may result in quadriceps weakness and delay mobilization 2
- Do not rely solely on adductor canal blocks for complete analgesia, as they primarily block anterior knee pain but may not adequately control posterior knee pain 5
- Be cautious with bilateral blocks in elderly patients or those with significant comorbidities due to increased risk of local anesthetic systemic toxicity; consider reducing the total dose of local anesthetic 1
- Monitor for motor blockade and numbness, which occur less frequently with adductor canal blocks compared to epidural analgesia but can still impact early mobilization 6
Alternative or Supplementary Techniques
- Consider adding iPACK (interspace between popliteal artery and capsule of posterior knee) blocks to bilateral adductor canal blocks if posterior knee pain is a significant concern, though the clinical benefit may be modest 5
- Avoid epidural analgesia due to increased risk of serious adverse events without superior benefits compared to peripheral nerve blocks 1, 6
- A combination of femoral and sciatic nerve blocks is not recommended over adductor canal blocks due to limited and inconsistent evidence 1
By implementing this comprehensive bilateral adductor canal block protocol as part of a multimodal analgesic approach for bilateral TKR, patients can experience effective pain control with preserved quadriceps function, facilitating early mobilization and rehabilitation.