Duchenne muscular dystrophy for tendon surgery9-year-old boy, 30 kg, with Duchenne muscular dystrophy
Muscular dystrophy: volatile-induced hyperkalaemic arrest and paediatric life support
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Know this first
- Suxamethonium is contraindicated: rhabdomyolysis, hyperkalaemia and cardiac arrest.
- Volatiles alone can trigger rhabdomyolysis; use a trigger-free technique.
- Cardiac depression and arrhythmias can be set off by anaesthesia or stress.
- Breathing can fail up to 36 hours after surgery.
- Hyperkalaemic arrest: calcium, insulin with glucose, bicarbonate, alongside CPR.
The patient
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Consider
What are your concerns?
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- A 9-year-old with Duchenne on long-term steroids, for elective tendon lengthening. Patient
- As a boy with Duchenne, his heart and lungs may be weaker than his walking suggests.
- Cardiomyopathy and arrhythmias come with the disease; his heart hasn't been imaged for 2 years. Disease
- Weak cough and swallow raise aspiration and chest risk, even 36 hours afterwards.
- Suxamethonium and volatiles can cause rhabdomyolysis and hyperkalaemic arrest in him.
Prepare
How do you prepare him?
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- Echo and ECG before surgery, with cardiology review of his function. Disease
- Cough strength and lung function reviewed; physiotherapy planned for afterwards.
- Four years on prednisolone puts him at adrenal risk: IV hydrocortisone cover per protocol.
- Trigger-free machine and circuit; dantrolene available in theatre.
- Regional blocks planned; they spare general agents and help his chest. After surgery
Plan
What is your anaesthetic plan?
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- TIVA with propofol and remifentanil; no volatile and no suxamethonium. Disease
- Rocuronium only if needed, titrated by train-of-four; his weakness may make it unnecessary. Airway
- Nerve blocks for his tendon surgery to limit opioids. After surgery
- ECG watched closely: a peaked T wave means hyperkalaemia until proven otherwise. Disease
- HDU afterwards, as his breathing can fail up to 36 hours later. After surgery
Crisis
Twenty minutes after a colleague's sevoflurane induction, T waves peak, then VF; no pulse. What do you do?
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- PALS arrest, shockable VF, from hyperkalaemia after volatile in Duchenne: call for help, start CPR. (Crisis)
- Volatile off; switch to TIVA with a clean circuit.
- First shock 2 J/kg, later shocks 4 J/kg; adrenaline 0.01 mg/kg after the second shock, then every 3–5 min.
- Calcium chloride 10%, 20 mg/kg IV, to protect his myocardium.
- Insulin 0.1 units/kg IV with 10% glucose 5 mL/kg, and bicarbonate 1 mEq/kg.
- CPR continues while potassium falls; ECPR if he doesn't respond.
Crisis
After return of circulation, how do you continue?
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- Potassium, CK, gases and urine myoglobin checked. (After surgery)
- This is rhabdomyolysis, MH-like; dantrolene if his temperature and CO2 climb.
- PICU, echo of his heart, and his family told to avoid triggers for life.
Fatal mistakes
- Suxamethonium in a boy with Duchenne.
- Volatile maintenance in Duchenne.
- No calcium in a hyperkalaemic arrest.
Checked against: Stoelting 8e · Barash 9e · AHA and AAP guidelines: pediatric advanced life support (2025) · AHA guidelines: special circumstances of resuscitation (2025)
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