Table 1.

Overview of the most common muscular dystrophies and mitochondrial disorders with specific anesthetics implications and notable features for each [3,4].

Neuromuscular Disorder	Notable Features
Muscular dystrophies (MD)	Muscle diseases with spectrum of severity including focal or diffuse weakness and cardiac dysfunction.
Becker MD	Progressive weakness with calf hypertrophy with preservation of neck flexor strength; serum CK > 5× normal; average onset cardiomyopathy 14.6 years old. X-linked, altered dystrophin expression.
Duchenne MD	Progressive weakness with calf hypertrophy; serum CK > 10× normal; 50% with cardiomyopathy by age 18 years. X-linked, absent dystrophin expression.
Emery–Dreifuss MD	Joint contractures, progressive weakness, cardiac involvement; cardiac conduction defects and/or cardiomyopathy. EMD, FHL1, LMNA gene involvement.
Limb-girdle MD	Skeletal muscle involvement with variable progression. Multiple subtypes based on autosomal dominant or recessive traits.
Mitochondrial disorders	Abnormalities of mitochondrial respiratory chain with heterogenous manifestations commonly including ophthalmoplegia, myopathy, cardiomyopathy, encephalopathy, seizures, and spasticity.
Kearns–Sayre syndrome (KSS)	Pigmentary retinopathy and external ophthalmoplegia; elevated lactate; cardiac conduction abnormalities; ragged-red fibers on muscle biopsy. Mitochondrial DNA (mtDNA) deletion
Leigh syndrome	Hypotonia, movement disorders due to brainstem and/or basal ganglia involvement; hypertrophic cardiomyopathy; elevated lactate. mtDNA variant (MT-ATP6 most common) or mtDNA deletion.
Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS)	Elevated lactate and seizures; ragged red fibers on muscle biopsy; hypertrophic cardiomyopathy; pigmentary retinopathy. mtDNA defect (MT-TL1).
Myoclonus epilepsy with ragged red fibers (MERRF)	Myopathy, blindness, deafness; elevated lactate; cardiomyopathy with Wolff–Parkinson–White (WPW) syndrome. mtDNA variant (MT-TK most common).
Neuropathy, ataxia and retinitis pigmentosa (NARP)	Late-childhood or adult onset; basal ganglia involvement. mtDNA variant (MT-ATP6 most common).
Pearson syndrome	Sideroblastic anemia, pancreatic dysfunction. mtDNA deletion.
Progressive external ophthalmoplegia (PEO)	Ptosis, ophthalmoplegia and proximal limb weakness; presentation similar to KSS. mtDNA deletion.

CK: creatinine kinase.