الفهرس 
Pathophysiology of MHOnly 14 pages are availabe for public view
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Abstract
Malignant hyperthermia susceptibility (MHS) is a pharmacogenetic
disorder of skeletal muscle calcium regulation associated with
uncontrolled skeletal muscle hypermetabolism. Manifestations of
malignant hyperthermia (MH) are precipitated by certain agents, either
conventional such as depolarizing muscle relaxant (specifically,
succinylcholine) or even volatile anesthetics (e.g. isoflurane), and also
can be triggered by certain newly discovered drugs including
(serotonergic drugs, phosphodiesterase type III inhibitors, statins,
ondansteron, methylene blue, tetracaine).
The triggering substances release calcium stores from the
sarcoplasmic reticulum and may promote entry of calcium from the
myoplasm, causing contracture of skeletal muscles, glycogenolysis, and
increased cellular metabolism, resulting in production of heat and excess
lactate. Affected individuals experience: acidosis, hypercapnia,
tachycardia, hyperthermia, muscle rigidity, compartment syndrome,
rhabdomyolysis with subsequent increase in serum creatine kinase (CK)
concentration, hyperkalemia with a risk for cardiac arrhythmia or even
arrest, and myoglobinuria with a risk for renal failure. MH may occur in
the early postoperative period and can recur in the intensive care unit in
following 24 to 48 hours. Without proper and prompt treatment with
dantrolene sodium, mortality is extremely high.