What is the most appropriate management strategy for acute pain in a patient with opioid use disorder taking buprenorphine (Suboxone)/naloxone, who has severe pain after an exploratory laparotomy, right femur fracture, and pelvic fracture?

Management of Acute Severe Pain in a Patient on Buprenorphine for Opioid Use Disorder

Continue the patient's buprenorphine 16 mg daily and aggressively treat acute pain with high-dose short-acting full opioid agonists (such as IV hydromorphone or fentanyl) at shorter intervals than typical, combined with multimodal non-opioid analgesics and the regional block already performed.

Rationale for Continuing Buprenorphine

The most recent expert consensus strongly recommends continuing buprenorphine during the perioperative period rather than discontinuing it, particularly for patients with opioid use disorder 1. This represents a paradigm shift from older recommendations that advocated for discontinuation 1.

• Discontinuing buprenorphine places patients with OUD at extremely high risk for relapse to opioid use, which carries significant morbidity and mortality 2, 3.
• The 2019 PAIN Network guidelines note that more recent advisories propose continuation of buprenorphine depending on preoperative dose, with patients taking ≤16 mg particularly suitable for continuation 1.
• This patient is already post-operative (emergent trauma surgery), making preoperative discontinuation impossible 1.

Acute Pain Management Strategy

Primary Approach: Full Opioid Agonists at Higher Doses

• Add short-acting full mu-opioid agonists (morphine, hydromorphone, fentanyl, or oxycodone) to the continued buprenorphine regimen 1, 4, 5.
• Expect to use significantly higher doses at shorter intervals than for opioid-naive patients due to opioid tolerance and cross-tolerance 1, 5, 2.
• Use scheduled dosing rather than PRN to prevent pain from recurring and to minimize patient anxiety about pain control 1, 4, 5.
• The American College of Physicians specifically recommends continuing maintenance opioid therapy (buprenorphine or methadone) and adding short-acting opioids for breakthrough pain 1, 4.

Why Full Agonists Work Despite Buprenorphine

• While buprenorphine has high mu-receptor affinity, full agonists can still provide analgesia when given in sufficient doses 2, 6.
• At the patient's dose of 16 mg daily, there is partial receptor blockade, but this can be overcome with higher opioid doses 1.
• Evidence suggests adequate analgesia can be achieved with buprenorphine continuation plus breakthrough opioids 2, 3.

Multimodal Analgesia is Essential

• Maximize non-opioid analgesics: scheduled acetaminophen (already started), NSAIDs if not contraindicated by trauma/bleeding risk 1.
• Consider IV ketamine as an adjunct for severe pain, particularly given the high-pain nature of femur and pelvic fractures 1.
• Optimize the TAP block that was already performed and consider additional regional techniques if feasible 1.
• Add adjuvant analgesics such as gabapentin/pregabalin, lidocaine infusion, or dexmedetomidine 1.

Why Other Options Are Inappropriate

Option A (Discontinue buprenorphine, start fentanyl): INCORRECT

• Discontinuing buprenorphine in a patient with OUD creates high risk for relapse and destabilization of their recovery 1, 2, 3.
• This contradicts current best practice guidelines that prioritize continuation 1.

Option B (Double buprenorphine dose): INCORRECT

• While dividing buprenorphine into q6-8h dosing can leverage its analgesic properties, simply doubling the dose is not supported by guidelines 1.
• Buprenorphine alone is insufficient for severe acute pain from major trauma 1, 2.

Option C (Continue buprenorphine + PRN hydrocodone): PARTIALLY CORRECT but SUBOPTIMAL

• This is closer to the correct answer but has critical flaws:
  • PRN dosing is inferior to scheduled dosing for severe acute pain 1, 4, 5.
  • Hydrocodone is a weaker opioid; IV options (hydromorphone, fentanyl, morphine) are preferred for severe pain in the ICU setting 1, 2.
  • The patient needs aggressive, scheduled opioid therapy, not PRN 1, 5.

Option D (Discontinue naloxone, start methadone): INCORRECT

• The naloxone component in buprenorphine/naloxone has minimal systemic absorption when taken sublingually and is not the barrier to pain control 1.
• Switching to methadone is complex, requires careful conversion, and is typically reserved for planned perioperative management, not acute emergent situations 1.
• This option still involves discontinuing buprenorphine, risking OUD destabilization 1, 2.

Option E (Discontinue buprenorphine, start IV ketamine): INCORRECT

• While ketamine is an excellent adjunct, it should not replace buprenorphine 1.
• Ketamine alone is insufficient as the sole analgesic for this degree of trauma 1.
• Again, discontinuing buprenorphine risks relapse 2, 3.

Practical Implementation

1. Continue buprenorphine 16 mg daily (can be divided to 8 mg q12h or 4 mg q6h to enhance analgesic effect) 1.
2. Initiate scheduled IV opioids: Start with hydromorphone 1-2 mg IV q2-3h or fentanyl 50-100 mcg IV q1-2h, titrating upward as needed 1, 2.
3. Maximize non-opioid adjuncts: Scheduled acetaminophen 1g q6h, ketorolac 15-30 mg IV q6h (if no contraindication), IV ketamine infusion 0.1-0.3 mg/kg/hr 1.
4. Monitor closely for respiratory depression with naloxone readily available, though risk is manageable with appropriate monitoring 1, 4.
5. Coordinate with the patient's buprenorphine provider to ensure continuity of OUD treatment 1.
6. Reassure the patient that his addiction treatment will continue and pain will be aggressively managed 1, 4, 5.

Critical Pitfalls to Avoid

• Do not undertreat pain due to fear of addiction or "opiophobia"—this patient already has OUD and is in recovery; undertreating pain risks pseudoaddiction and treatment disengagement 1, 5, 3.
• Do not use mixed agonist-antagonists (pentazocine, nalbuphine, butorphanol) as they can precipitate acute withdrawal 1, 4, 5.
• Do not discontinue buprenorphine without compelling reason, as this jeopardizes OUD recovery 1, 2, 3.
• Do not rely on PRN dosing alone for severe acute pain—scheduled dosing prevents pain recurrence and reduces patient anxiety 1, 4, 5.