Anaesthetic Implications of Nemaline Rod Myopathy

Nemaline rod myopathy is an inherited congenital myopathy first described in 1963. Affected patients characteristically present in infancy with a non-progressive hypotonia and symmetrical muscle weakness. The disease affects all skeletal muscles including the diaphragm with sparing of cardiac and other muscle. Facial dysmorphism is common as are skeletal deformities, including kyphosis, scoliosis and pectus excavatum. We present two sisters with nemaline rod myopathy and their anaesthetic management for scoliosis surgery. Facial dysmorphism was a feature of both cases. Preoperatively, both patients demonstrated poor respiratory function on pulmonary function testing. Both cases were successfully managed using controlled ventilation and inhalational anaesthetic agents, avoiding muscle relaxants. Postoperatively, there were no respiratory complications. Although one case report describes the use of succinylcholine and pancuronium in a patient with nemaline rod myopathy, we feel that neuromuscular blocking agents should be avoided where possible and only used with careful monitoring.