Learning objectives

• Signs and symptoms of Duchenne muscular dystrophy
• Anesthetic management of Duchenne muscular dystrophy

Definition and mechanisms

• Duchenne is an x-linked genetic disorder characterized by progressive muscle weakness and atrophy
• It is a multi-systemic condition and affects striated, smooth, and cardiac muscles
• Duchenne muscular dystrophy is the most common and severe form of muscular dystrophies, a group of genetically determined primary degenerative myopathies
• Duchenne is caused by a mutation in the gene that encodes for dystrophin, a protein that is essential to the proper functioning of our muscles
• Without dystrophin, muscles are not able to function or repair themselves properly
• Duchenne symptom onset is in early childhood (around the age of 4 years) and affects primarily males
• The prevalence is approximately 6 per 100,000 individuals
• Affected males are often wheelchair-bound before their teens and suffer from contractures, marked scoliosis, restrictive lung function, and cardiomyopathies
• The disease progresses differently for every person and the average life expectancy is 26-30 years
• Duchenne becomes eventually fatal due to respiratory or cardiac failure in the second or third decade

Signs and symptoms

• Muscle weakness
• Developmental delay
• Delayed speech and language development
• Enlargement of the calves
• Fatigue
• Difficulty climbing stairs
• Toe walking
• Frequent falls
• Lumbard lordosis
• Cardiomyopathy
• Shortness of breath
• Cognitive impairement
• Particular ECG pattern: Q-waves in the lateral leads, increased ST-segments, poor R-wave progression, resting tachycardia, and conduction defects
• Respiratory failure

Treatment

• No cure available
• Manage symptoms with supportive therapy:
  • Corticosteroids
  • ACE inhibitors and/or beta-blockers to slow the progression of cardiomyopathy
  • Physical therapy
  • Braces
  • Surgery to treat scoliosis and contractures
  • Exercise
  • Tracheostomy and assisted ventilation for respiratory failure
  • Anticonvulsants to control seizures
  • Immunosuppressants to delay muscle damage

Management

Suggested reading

• Duan, D., Goemans, N., Takeda, S. et al. Duchenne muscular dystrophy. Nat Rev Dis Primers 7, 13 (2021).
• Pollard BJ, Kitchen, G. Handbook of Clinical Anaesthesia. Fourth Edition. CRC Press. 2018. 978-1-4987-6289-2.
• Marsh, S., Pittard, A., 2011. Neuromuscular disorders and anaesthesia. Part 2: specific neuromuscular disorders. Continuing Education in Anaesthesia Critical Care & Pain 11, 119–123.
• Lerman, J., 2011. Perioperative management of the paediatric patient with coexisting neuromuscular disease. British Journal of Anaesthesia 107, i79–i89.
• Ragoonanan, V., Russell, W., 2010. Anaesthesia for children with neuromuscular disease. Continuing Education in Anaesthesia Critical Care & Pain 10, 143–147.