Anaesthetic Management of a Child with Muscular Dystrophy
Total intravenous anesthesia (TIVA) with propofol and remifentanil, administered separately (not mixed), avoiding or minimizing neuromuscular blocking agents, represents the safest approach for children with muscular dystrophy.
Key Anesthetic Principles
Avoid or Minimize Muscle Relaxants
- Children with muscular dystrophy demonstrate heightened sensitivity to neuromuscular blocking agents, leading to prolonged paralysis, delayed recovery, and increased risk of respiratory complications 1, 2.
- Successful tracheal intubation can be achieved without muscle relaxants using adequate doses of propofol and remifentanil 1, 2.
- If muscle relaxants are absolutely necessary (e.g., in myotonic dystrophy cases), use minimal doses with careful train-of-four monitoring and ensure complete reversal before extubation 3.
TIVA Technique
- Propofol (150-250 mcg/kg/min) combined with remifentanil (0.3-0.55 mcg/kg/min) as separate infusions provides optimal conditions for intubation, maintenance, and rapid recovery 1, 2, 4.
- This technique achieves controlled hypotension when needed (important for spinal surgery), stable hemodynamics, and rapid emergence 1.
- The short context-sensitive half-life of both agents allows predictable recovery, critical in patients at risk for prolonged respiratory depression 4.
Critical Safety Consideration
- Never mix propofol and remifentanil in the same syringe 5.
- Mixing creates pharmaceutical instability, unpredictable drug delivery (remifentanil passively follows propofol TCI rates rather than being independently controlled), and medicolegal liability as it constitutes an unlicensed drug 5.
- Rapid increases in propofol target concentration cause dangerous remifentanil peaks risking apnea, bradycardia, and hypotension 5.
Specific Monitoring Requirements
- Continuous cardiac monitoring (increased risk of cardiomyopathy, especially in Duchenne muscular dystrophy) 1.
- Capnography and pulse oximetry throughout the perioperative period 4.
- Temperature monitoring (risk of malignant hyperthermia-like reactions, though true MH is controversial) 1.
- If muscle relaxants used: mandatory train-of-four monitoring 3.
Postoperative Management
- Plan for extended postoperative monitoring due to increased risk of respiratory complications and sensitivity to residual anesthetic effects 1, 4.
- Ensure complete return of airway reflexes and adequate spontaneous ventilation before extubation 4.
- Consider regional anesthesia adjuncts (e.g., intrathecal morphine for spinal surgery) to minimize systemic opioid requirements postoperatively 1.
Common Pitfalls to Avoid
- Using volatile anesthetics in Duchenne muscular dystrophy (risk of rhabdomyolysis and hyperkalemic cardiac arrest) 1.
- Administering succinylcholine (absolutely contraindicated due to risk of hyperkalemia and cardiac arrest) 1.
- Inadequate postoperative respiratory monitoring leading to delayed recognition of respiratory failure 4.
- Mixing propofol and remifentanil, which creates uncontrolled remifentanil delivery and pharmaceutical instability 5.