| Myasthenia congenita: Like adult myasthenia gravis.
Myositis ossificans: Bony infiltration of tendons, fascia,
aponeuroses and muscle. Thoracic involvement greatly reduces thoracic
compliance. Progressive respiratory failure. Check respiratory
function, history of steroid therapy. Airway and intubation problems
if neck rigid and mouth fixed.
Myotonia congenita (Thomsen's disease):
Decreased ability to relax muscles after contraction. Diffuse
hypertrophy of muscle. Anesthetic implications: Avoid relaxants
and depressants, as for myotonic dystrophy, although this is a
more benign disease, non-progressive.
Myotonic dystrophy (myotonia dystrophica):
Weakness, myotonia, ptosis, cataracts, partial baldness
and gonadal atrophy. Cardiac conduction defects and arrhythmias.
Impaired ventilation. Anesthetic implications: Avoid succinylcholine
which causes myotonia in 50%. Non-depolarizing drugs do not relax
myotonia. Neostigmine induces myotonia. Monitor ECG. Extremely
sensitive to respiratory depressants, use regional or inhalational
agents. IPPV postoperatively if necessary. Halothane may cause
postoperative shivering and myotonia. Pulmonary complications
due to poor cough.
Nail-patella syndrome: Dysplasia of nails and absent or
hypoplastic patellas. May have iliac horns, abnormality of elbows,
nephropathy, increased mucopolysaccharide excretion. Anesthetic
implications: Care with drugs excreted by kidneys.
Neonatal hypoglycemia (idiopathic): Symptomatic
hypoglycemia in infancy - convulsions, lethargy and mental retardation
if untreated. No ketosis. Therapy - subtotal pancreatectomy. See
also Beckwith's syndrome. Anesthetic
implications: Start IV glucose infusion preoperatively. Boluses
of glucose may precipitate rebound hyperglycemia. Extreme care
in monitoring blood glucose perioperatively. Steroids, diazoxide
and glucagon as required. After pancreatectomy may require insulin
and glucose to maintain blood sugar in normal limits.
Neuroleptic malignant syndrome: see
under
Malignant Hyperthermia, Associated Disorders.
Niemann-Pick disease: Hepatosplelomegaly and accumulation
of sphingomyelin and other lipids throughout body (see also Wolfman's disease). Marrow, liver, and spleen
involvement lead to anemia and thrombocytopenia. Diffuse foam
cell infiltration of lungs leads to pulmonary insufficiency or
pneumonia. Anesthetic implications: Check coagulation parameters
and cardiorespiratory function.
Noack’s syndrome: Craniosynostosis and
digital anomalies. Obesity. Anesthetic implications: May be difficult
to intubate because of skull deformity. |