Rhabdomyolysis is a condition in which damaged

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Rhabdomyolysis is a condition in which damaged skeletal muscle tissue breaks down rapidly. Breakdown products of damaged muscle cells are released into the bloodstream; some of these, such as the protein myoglobin, are harmful to the kidneys and may lead to kidney failure. The severity of the symptoms, which may include muscle pains, vomiting and confusion, depends on the extent of muscle damage and whether kidney failure develops. The muscle damage may be caused by physical factors strenuous exercise, medications, drug abuse, and infections. Some people have a hereditary muscle condition that increases the risk of rhabdomyolysis. The diagnosis is usually made with blood tests and urinalysis. The mainstay of treatment is generous quantities of intravenous fluids, but may include dialysis or hemofiltration in more severe cases. QUESTIONS 1. What is the effect of hyperkalemia on cell membrane potential? 2. What is responsible for the repolarizing phase of an action potential? 3. What is the effect of prolonged depolarization on the skeletal muscle Na+ channel? ANWERS 1. Hyperkalemia causes depolarization of the cell membrane potential. 2. Repolarization phase of an action potential results from activation of voltage-gated K+ conductance and inactivation of Na+ conductance. 3. Prolonged depolarization on the skeletal muscle Na+ channel leads to inactivation of Na+ channels.
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Title of the case: Woman with jaw weakness Student’s Name: LEBURA EWONUBARI GRACE Roll #: 666 Medical Physiology Clinical Case SOAP Notes Subjective Observations Possible physiological explanations Jill Rothman, 26. Muscle weakness in the face. Jaw gets tired as she chews and swallowing is difficult. Double vision which seems to come on late in the evening particularly after reading for a few minutes. Upper arm weakness. Weakening of the muscles of the face and eyes due to lack of impulse transmission. By damaging the acetylcholine receptors on the sarcolemma, these antibodies are causing interference with normal contraction impulse transmission between the motor neurons and muscle fibers. Acetylcholine can’t bind to the muscle cell, so an action potential can’t develop and contraction won’t occur.
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Objective observations Possible physiological explanations Ptosis (drooping) of both eyelids after repeated blinking exercises. Appears snarling when smiling. Electromyographic testing revealed progressive weakness and decreased amplitude of contraction of the distal arm muscles upon repeated mild shocks (5 shocks per second) of the ulnar and median nerves. Intravenous administration of endrophonium reversed the symptoms and electromyographic findings within 40 secs. Neurological examination involving testing muscles and reflexes may cause abnormal eye movements, inability to move the eyes normally, and drooping eyelids.
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