Opioid-tolerant patient with chronic pain and acute surgical abdomen
A 44-year-old woman with chronic pancreatitis and a history of opioid use disorder (currently on buprenorphine 16 mg daily, stable for 2 years) presents with 18 hours of severe epigastric pain, vomiting and distension. She is tachycardic at 118, BP 132/78, afebrile, with a rigid upper abdomen and no bowel sounds. CT shows a large fluid collection and free gas. She is anxious and states she does not want 'to be put back on that stuff'. She is awaiting emergency laparotomy. Her regular medications include buprenorphine, pregabalin and sertraline.
1. Discuss the analgesic plan for the perioperative period, addressing her buprenorphine and her stated wish to avoid opioids.
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Her acute surgical pathology requires effective analgesia, and untreated pain is itself a risk for relapse and for delayed mobilisation and respiratory complications. Her stated wish should be respected as a goal but discussed realistically: she needs to understand that short-term, supervised opioid use for an acute surgical insult is not a return to misuse, and that withholding analgesia is not protective. Buprenorphine has high receptor affinity and partial agonism; at 16 mg it can attenuate the effect of full agonists. Options: continue buprenorphine at a reduced dose (e.g. 8 to 12 mg) or split dosing, with acute pain managed by additional short-acting full agonist titrated to effect, or divide the buprenorphine and use higher agonist doses; alternatively, in a supervised setting, convert to a full agonist with clear documentation, though this is less preferred in someone stable on buprenorphine. Do not stop buprenorphine abruptly, as that risks withdrawal and destabilisation. Multimodal adjuvants: continue pregabalin (renal dosing), regular paracetamol, NSAID only if renal function and bleeding risk allow, ketamine infusion at low dose for opioid-sparing effect, and consider a thoracic epidural or rectus sheath block depending on the incision. Involve the acute pain service and addiction medicine early, plan for postoperative nausea and constipation prophylaxis, and arrange follow-up to prevent relapse. Her sertraline should continue; be alert to serotonin toxicity if multiple serotonergic agents are added.
2. What would you do if, on the morning of surgery, she discloses that she has been using illicit fentanyl for the past week in addition to her buprenorphine?
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This disclosure changes the risk profile and must be handled without judgement, because honesty protects her. It means her tolerance is higher and unpredictable, her buprenorphine may be partially displaced, and she is at risk of withdrawal and of adulterant toxicity. Actions: thank her and reassure her that this will not delay necessary surgery; inform the anaesthetic and surgical teams and addiction medicine; check for signs of opioid toxicity or withdrawal; obtain a toxicology screen if it will change management (e.g. co-ingestants such as benzodiazepines or xylazine), but do not make surgery conditional on it. Analgesic plan: expect higher full-agonist requirements intraoperatively and postoperatively; use multimodal techniques including regional anaesthesia where feasible, ketamine, and regular adjuvants; monitor closely for respiratory depression, especially if she is also given benzodiazepines or gabapentinoids. Plan for withdrawal management with the addiction team, offer take-home naloxone and harm-reduction advice, and arrange urgent follow-up. Document the discussion neutrally. The key exam point is that punitive or withholding responses discourage disclosure and increase risk; the safe approach is to escalate support and tailor analgesia.