When should we start weaning patients off oxycodone (opioid analgesic) after bilateral total knee arthroplasty (TKA)?

When to Wean Oxycodone After Bilateral Total Knee Arthroplasty

Begin tapering oxycodone gradually by 25-50% every 2-4 days once pain intensity decreases to moderate or low levels, typically starting 48-72 hours postoperatively when multimodal non-opioid analgesia can adequately control pain. 1

Immediate Postoperative Period (0-48 hours)

Strong opioids like oxycodone are recommended for high-intensity pain during the immediate postoperative period and should be combined with multimodal non-opioid analgesia rather than used as monotherapy. 2

• Administer oxycodone via IV patient-controlled analgesia (PCA) during the first 24-48 hours for superior pain control and patient satisfaction compared to nurse-administered regimens. 2
• Ensure bilateral adductor canal blocks or femoral nerve blocks are in place to minimize opioid requirements from the outset. 3, 4
• Implement scheduled paracetamol and NSAIDs/COX-2 inhibitors (unless contraindicated) as the foundation of your analgesic regimen. 2, 3

Transition Phase (48-72 hours)

This is the critical window to begin transitioning from strong opioids to weaker opioids or non-opioid analgesia.

• Monitor pain intensity closely during physical therapy sessions—if pain scores decrease to moderate levels (VAS 3-5) with multimodal analgesia, begin the weaning process. 5
• Switch from IV oxycodone to oral formulations before initiating dose reductions. 1
• Weak opioids are recommended for moderate or low-intensity pain when non-opioid analgesia alone is insufficient. 2

Weaning Protocol

Follow the FDA-recommended tapering schedule to prevent withdrawal symptoms in physically dependent patients:

• Reduce the oxycodone dose by 25-50% every 2-4 days while monitoring for signs and symptoms of withdrawal. 1
• If withdrawal symptoms develop (anxiety, sweating, restlessness, increased pain), increase the dose back to the previous level and taper more slowly by either increasing the interval between decreases or reducing the amount of dose change. 1
• Never abruptly discontinue oxycodone in patients who have been taking it regularly, as physical dependence can develop even after short-term use. 1

Multimodal Analgesia to Facilitate Weaning

Optimize non-opioid analgesics to enable successful opioid weaning:

• Continue scheduled paracetamol 1g every 4-6 hours throughout the weaning period. 2, 3, 6
• Maintain NSAIDs or COX-2 inhibitors for their opioid-sparing effects, assessing individual patient risks (cardiovascular, renal, GI). 2
• Consider continuous adductor canal catheter infusions rather than single-shot blocks for extended analgesia during the weaning period. 3, 4
• Implement cooling and compression techniques to reduce inflammation and pain. 3, 4

Special Considerations for Bilateral TKA

Bilateral procedures present unique challenges that may prolong opioid requirements:

• Patients undergoing bilateral TKA typically experience higher pain intensity and may require strong opioids for a longer duration (up to 72-96 hours) compared to unilateral procedures. 4
• Exercise particular caution with bilateral adductor canal blocks in elderly patients or those with comorbidities, as reduced local anesthetic doses may provide less robust analgesia, potentially increasing opioid needs. 3, 4

Timeline for Complete Discontinuation

Most patients should be completely off oxycodone by hospital discharge (typically 2-3 days post-bilateral TKA) or within 5-7 days maximum:

• Evidence demonstrates that controlled-release oxycodone during inpatient rehabilitation can reduce hospital stay by 2.3 days, suggesting most patients achieve adequate pain control with non-opioid analgesia by day 3-5. 5
• Patients using multimodal analgesia with regional blocks can achieve satisfactory pain control (VAS 0-3) without opioids by 48 hours postoperatively. 6

Common Pitfalls to Avoid

• Do not continue opioids beyond the acute pain phase (>7 days) without reassessing the source of persistent pain, as this increases risk of chronic opioid use. 1
• Do not rely on "as-needed" opioid dosing alone—this leads to inadequate pain control and delayed functional recovery. 5
• Do not use weak opioids for high-intensity pain—they are ineffective and delay appropriate treatment. 2
• Monitor carefully for opioid-related adverse effects (nausea, sedation, respiratory depression) that may necessitate earlier weaning. 1, 7