What is the recommended anaesthetic approach for children with muscular dystrophy undergoing surgery?

Anesthetic Approach for Children with Muscular Dystrophy

Use total intravenous anesthesia (TIVA) with propofol and remifentanil while avoiding or minimizing neuromuscular blocking agents in children with muscular dystrophy undergoing surgery.

Recommended Technique

The optimal anesthetic strategy centers on TIVA because children with muscular dystrophy have heightened sensitivity to volatile anesthetics, muscle relaxants, and face significant risks of malignant hyperthermia-like reactions, prolonged paralysis, and respiratory complications 1, 2.

Core Anesthetic Regimen

Induction:

• Propofol bolus (2-3 mg/kg) combined with remifentanil (1-2 mcg/kg bolus or 0.5-1 mcg/kg/min infusion) 1, 2
• Atropine premedication (0.01-0.02 mg/kg) to prevent vagal responses 3
• Tracheal intubation can be achieved successfully without muscle relaxants using adequate propofol/remifentanil dosing 1, 2

Maintenance:

• Propofol infusion: 150-250 mcg/kg/min 1, 2, 3
• Remifentanil infusion: 0.3-0.55 mcg/kg/min 1, 2, 3
• Adjust based on surgical stimulation and hemodynamic response

Muscle Relaxant Considerations

Avoid muscle relaxants entirely when possible - this is the safest approach as it eliminates risks of prolonged paralysis and hyperkalemic cardiac arrest 1, 2. The propofol-remifentanil combination provides adequate intubating conditions without neuromuscular blockade 1, 2.

If muscle relaxants are absolutely necessary (rare circumstances):

• Use minimal doses with careful train-of-four monitoring 4
• Avoid succinylcholine completely due to hyperkalemia and rhabdomyolysis risk
• Consider short-acting non-depolarizing agents with extreme caution
• Ensure complete reversal with anticholinesterases before extubation 4

Critical Monitoring and Safety Measures

Intraoperative monitoring must include:

• Standard ASA monitors (ECG, non-invasive blood pressure, pulse oximetry, capnography, temperature) 3
• Precordial stethoscope for early detection of cardiac complications 3
• Train-of-four monitoring if any muscle relaxant is used 4
• Core temperature monitoring (risk of malignant hyperthermia-like reactions)

Ventilation strategy:

• Manual or mechanical controlled ventilation throughout the procedure 3
• Avoid nitrous oxide when possible; use air-oxygen mixture 3
• FiO₂ 0.4-0.5 typically adequate 3

Specific Disease Considerations

The technique has been successfully applied across different muscular dystrophy subtypes:

• Duchenne muscular dystrophy: Most common and highest risk; TIVA without relaxants is well-established 1, 2
• Myotonic dystrophy: TIVA effective even in very young infants (10 months) 4
• Werdnig-Hoffmann disease: TIVA safe in infants as young as 1 year 3

Postoperative Management

Plan for extended monitoring:

• Rapid emergence typically occurs 8-10 minutes after stopping infusions 3
• Monitor respiratory function closely for several hours postoperatively 1
• Ensure adequate analgesia is established before emergence, as propofol/remifentanil provide no residual analgesia 1, 5
• Consider regional anesthesia or intrathecal morphine for major procedures to provide prolonged postoperative analgesia 1

Common Pitfalls to Avoid

• Never use volatile anesthetics as primary agents - increased risk of malignant hyperthermia-like reactions and cardiac complications
• Never use succinylcholine - risk of fatal hyperkalemia and rhabdomyolysis
• Do not assume standard muscle relaxant dosing is safe - even small doses can cause prolonged paralysis 1
• Do not extubate until fully awake with adequate spontaneous ventilation - respiratory muscle weakness persists postoperatively 1, 3
• Avoid propofol infusion syndrome - limit infusion duration and total dose, especially in infants; monitor for metabolic acidosis, rhabdomyolysis, and cardiac dysfunction 5