PROSPECT Guidelines for Pain Management in Total Knee Replacement
The PROSPECT guidelines recommend a multimodal approach for total knee arthroplasty (TKA) pain management, combining general anesthesia with femoral nerve block or spinal anesthesia with local anesthetic plus spinal morphine, supplemented with paracetamol, NSAIDs/COX-2 inhibitors, cooling techniques, and appropriate opioids based on pain intensity. 1
Primary Anesthetic and Analgesic Techniques
- General anesthesia combined with femoral nerve block is recommended as the primary technique for surgery and postoperative analgesia 1
- Alternatively, spinal anesthesia with local anesthetic plus spinal morphine can be used effectively 1
- More recent evidence suggests adductor canal blocks as an effective alternative to femoral nerve blocks, as they provide effective analgesia while better preserving quadriceps strength 2, 3
- Peripheral nerve blocks are generally preferred over epidural analgesia due to better side effect profile 2, 3
Multimodal Analgesic Protocol
- Paracetamol (acetaminophen) should be administered on a scheduled basis as a baseline analgesic 1, 2
- NSAIDs or COX-2 selective inhibitors should be added unless contraindicated 1, 4
- Strong intravenous opioids should be used for high-intensity pain 1
- Weak opioids should be used for moderate to low-intensity pain 1
- Cooling and compression techniques should be implemented to reduce local inflammation and pain 1, 2
- Local infiltration analgesia (LIA) is recommended as part of the multimodal approach 3, 5
- A single intra-operative dose of intravenous dexamethasone may be beneficial as part of the protocol 3
Optimization of Regional Anesthetic Techniques
- For extended analgesia, consider continuous peripheral nerve block catheter techniques rather than single-shot injections 2
- When using adductor canal blocks, proper technique is essential to ensure adequate coverage of the surgical area 2, 3
- Peri-articular local infiltration analgesia should be combined with peripheral nerve blocks for optimal pain control 3, 5
Common Pitfalls and Considerations
- Be cautious with bilateral blocks in elderly patients or those with significant comorbidities due to increased risk of local anesthetic systemic toxicity 2
- Opioids should be reserved as rescue analgesics in the postoperative period to minimize adverse effects 3, 4
- Intrathecal morphine (100 μg) should only be considered in hospitalized patients when both peripheral nerve blocks and local infiltration analgesia are not possible 3
- Digital applications and augmented physician rounds may enhance pain management outcomes beyond standard care 6
Emerging Trends in TKA Pain Management
- Opioid-sparing multimodal protocols have demonstrated better pain relief and earlier functional gains compared to traditional opioid-based protocols 5
- Non-opioid interventions such as gabapentinoids and ketamine may have a role in select patients, though more research is needed 4
- Continuous monitoring of pain scores and functional outcomes helps optimize the pain management strategy 6, 5