Neuromuscular disorders : NMD
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The purpose of this review is to alert non-anaesthesiologists to the various complications from which patients with neuromuscular disorders and those susceptible to malignant hyperthermia can suffer during anaesthesia. The patient's outcome correlates with the quality of consultation between anaesthesiologists, surgeons, neurologists and cardiologists. ⋯ This review provides a synopsis of pre-operative anaesthetic considerations and adverse drug effects on skeletal, cardiac and smooth muscle tissue. It describes the pathogenetic aspects of typical complications and introduces anaesthetic procedures for the various neuromuscular disorders, including regional anaesthesia for patients in whom a restriction of respiratory and/or cardiac function is predicted.
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Neuromuscul. Disord. · Dec 2004
Clinical TrialSleep disordered breathing in spinal muscular atrophy.
Sleep disordered breathing is a common but under-diagnosed complication causing sleep disturbance and daytime symptoms in children with spinal muscular atrophy. Non-invasive (positive pressure) ventilation is an established treatment of respiratory failure; its role in treatment of sleep disordered breathing though remains controversial. Aim of this study was to verify the hypothesis that nocturnal non-invasive ventilation has beneficial impact on breathing during sleep, sleep quality and daytime complaints in children with spinal muscular atrophy. ⋯ Non-invasive ventilation during sleep completely eliminated disordered breathing, normalized sleep architecture and improved symptoms (P<0.05 for all). In children with spinal muscular atrophy sleep disordered breathing may cause relevant impairment of sleep and well-being. Both can be highly improved by nocturnal non-invasive ventilation.
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Neuromuscul. Disord. · Jul 2004
Comparative StudyFunctional characterization of malignant hyperthermia-associated RyR1 mutations in exon 44, using the human myotube model.
Malignant hyperthermia (MH) is a pharmacogenetic disorder with an autosomal dominant inheritance. During exposure to triggering agents as volatile anaesthetics, affected individuals may develop a potentially fatal hypermetabolic syndrome caused by excessive calcium release from the sarcoplasmic reticulum in skeletal muscle. ⋯ Investigation of calcium homeostasis with the calcium sensitive probe Fura 2 showed a higher sensitivity to the ryanodine receptor agonists 4-chloro-m-cresol, caffeine and halothane for the myotubes derived from the mutation carriers as compared to those of the control group. The presence of RyR1 mutations with impact on calcium homeostasis emphasizes the functional significance of exon 44.
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Neuromuscul. Disord. · Jul 2004
Comparative StudyNew potent mexiletine and tocainide analogues evaluated in vivo and in vitro as antimyotonic agents on the myotonic ADR mouse.
The antimyotonic activity of chiral derivatives of mexiletine and tocainide, selected as potent use-dependent blockers of skeletal muscle sodium channels, was evaluated in vivo acutely in myotonic ADR mice. The compounds had either aromatic (Me4 and Me6) or branched isopropyl groups (Me5 and To1) on the asymmetric centre, or had this latter one methylene apart from the amino group (Me2). Therapeutic doses of mexiletine (5-10 mg/kg) and tocainide (7-20 mg/kg) significantly reduced the long time of righting reflex (TRR), typical of ADR mice. ⋯ On stimulus-evoked firing, the isopropyl analogues were 2-4-fold more potent than parent compounds, while the aromatic analogues were about 10-fold more potent than mexiletine. Patch-clamp recordings confirmed a normal-like pharmacological sensitivity of sodium channels of native ADR muscle fibres. Finally, the in vivo antimyotonic activity is due to the block of sodium channels and divergences with in vitro potency can be related to structure-based changes in drug pharmacokinetics.
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Neuromuscul. Disord. · Jun 2004
Case ReportsPneumothorax associated with long-term non-invasive positive pressure ventilation in Duchenne muscular dystrophy.
Long-term non-invasive positive pressure ventilation (NPPV) is effective for improving the quality of life and survival of neuromuscular patients. This treatment is usually easy to administer and severe complications have rarely been reported. We describe two cases in which the development of pneumothorax was associated with long-term NPPV administered to Duchenne muscular dystrophy patients. Given the wide scale utilization of chronic NPPV, we suggest that care-givers and patients be made aware of this serious complication.