الفهرس 
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Abstract
Muscular dystrophies (MDs) are a heterogeneous group of hereditary disorders characterized by muscle fiber necrosis and regeneration, leading to progressive weakness and degeneration of muscle.
The incidence rates of MDs vary depending on the specific type. Duchenne MD is the most common MD .
The first historical account of MD was reported by Conte and Gioja in 1836.
There have been several attempts at classifying the different types of muscular dystrophy (MD). Walton and Nattrass proposed an original classification scheme which depends on two considerations: the mode of inheritance and the distribution of predominant muscle weakness.
The pathophysiology of MD is dueto lack of dystrophin which involved in maintenance of muscle membrane integrity with dystrophin-associated glycoproteins (DAGs), which leads to cellular and membrane instability, with progressive leakage of intracellular components and elevation of creatine phosphokinase (CPK) levels.
Dead muscle shells are replaced by fibrofatty infiltrates. Loss of muscle units accounts for the weakness and contracture.
The heart is also affected to various degrees, depending on the stage of the disease and the type of mutation. Cardiac degeneration is due to replacement of myocardium by connective tissue or fat, which leads to dilated cardiomyopathy. Respiratory involvement is common in MD.
Preoperative preparation includes careful medical history and neurological examination and airway assessment. Any respiratory infection should be treated prior to surgery to minimize postoperative pulmonary complications The use of long-acting sedatives should be avoided .Preoperative cardiology assessment with an ECG and echocardiography is essential .careful preoperative pulmonary assessment is important with pulmonary function tests and arterial blood gases and chest x-ray. Electromyography is essential and routine laboratory tests are also done .
Patients with MD have altered responses to a number of anaesthetic medications. They are often very sensitive to even small doses of opioids, sedatives, and inhalational and intravenous(thiopental)agents,all of which may cause sudden and prolonged apnea. Premedication should therefore be avoided ,if possible
Succinylcholine is best avoided because of un predictable responses and the risks of inducing severe hyperkalemia or triggering malignant hyperthermia.Although some patients exhibit anormal response to nondepolarizing muscle relaxants, others may be very sensitive. Marked respiratory and circulatory depression may be seen with volatile anaesthetics in patients with advanced disease
Total intravenous anaesthesia (TIVA) with propofol, opioid anaesthesia and nondepolarizing neuromuscular blocker appear to be safe and effective anaesthetic techniques in patients with muscular dystrophy.It is advisable to use short-acting nondepolarizing neuromuscular blockers and monitor neuromuscular function until full recovery to avoid administration of anticholinesterases in these patients.
Regional or local anesthesia may be a good alternative to general anesthesia in that it avoids the risk of triggering agents and respiratory depression and enables the use of local anesthetics for postoperative analgesia. It may also facilitate chest physiotherapy.
There is a high incidience of anaesthetic complications which occurs with muscle dystrophy including rhabdomyolysis, cardiac complications, respiratory complications, myotonic reaction, masseter or generalized muscle spasm, autonomic dysfunction, malignant hyperthermia.
Careful postoperative care of patients with muscle dystrophy to avoid cardiac and respiratory complications .