Prolonged immobilization

There is an increased risk of post-operative thromboembolic complications in women taking oral contraceptives Ifposs-bte, use of the drug is discontinued at least 4 weeks before a surgical procedure associated with thromboembolism or during prolonged immobilization. 

Major surgery without prolonged immobilization Minor surgery without immobilization... 

CHCs are contraindicated in women with a history of thromboembolic events and in those at risk due to prolonged immobilization with major surgery unless they are taking anticoagulants. 

Postsurgical thromboembolism- Risk is increased 2- to 4-fold. If possible, discontinue OCs at least 4 weeks before and 2 weeks after surgery and during and following prolonged immobilization because OCs are associated with an increased risk of thromboembolism. 

At least two additional types of acetylcholine receptors are found within the neuromuscular apparatus. One type is located on the presynaptic motor axon terminal, and activation of these receptors mobilizes additional transmitter for subsequent release by moving more acetylcholine vesicles toward the synaptic membrane. The second type of receptor is found on perijunctional cells and is not normally involved in neuromuscular transmission. However, under certain conditions (eg, prolonged immobilization, thermal burns), these receptors may proliferate sufficiently to affect subsequent neuromuscular transmission. 

Androgens and anabolic steroids have been used in conjunction with dietary measures and exercises in an attempt to reverse protein loss after trauma, surgery, or prolonged immobilization and in patients with debilitating diseases. 

Hypercalcemia can result from an excessive intake of vitamin D. Prolonged immobilization can also result in hypercalcemia, as bone resorption increases with this immobilization, especially where there is concurrent renal failure (where the kidneys cannot excrete the excess calcium). Sudden, severe hypercalcemia results in vomiting, coma, and possibly death. Prolonged hypercalcemia can result in the formation of kidney stones and in the calcification of soft tissues, such as the eye. Stone formation and caiciheahon are more likely to occur with concurrent hyperphosphatemia. 

The most dangerous adverse effect of muscle relaxants in the ICU is suxamethonium-induced hyperkale-mic cardiac arrest (112-117). Prolonged immobilization is believed to result in a spread of immature acetylcholine receptors on the muscle surface, which may mediate massive long-lasting potassium release if suxamethonium is given (118). By this mechanism, cardiac arrest... 

An immediate rise in serum potassium occurs after the administration of suxamethonium. The rise is normally small, 0.5mmol/l or less (4). However, in some cases it can be larger, and cases of cardiac arrest associated with hyperkalemia have been reported in critically ill patients after prolonged immobilization (153-161). Cardiac arrest also occurred in a patient with wound botulism (162). 

Sato K, Nishiwaki K, Kuno N, Kumagai K, Kitamura H, Yano K, Okamoto S, Ishikawa K, Shimada Y. Unexpected hyperkalemia following succinylchohne administration in prolonged immobilized parturients treated with magnesium and ritodrine. Anesthesiology 2000 93(6) 1539-41. 

Prolonged bed rest is associated with increased urinary nitrogen excretion. Calcium, sodium, potassium, phosphate, and sulfate excretions are increased hydrogen ion excretion is reduced, presumably caused by decreased metabolism of skeletal muscle. The amplitude of circadian variation of plasma cortisol is reduced by prolonged immobilization, and the urinary excretion of catecholamines may be reduced to one third of the concentration in an active individual. Vanil-lylmandehc acid excretion is reduced by one fourth after 2 to 3 weeks of bed rest. 

Most other preanalytical factors are less lilcely to lead to confusion. Prolonged immobilization and bed rest can decrease bone density and increase total and free calcium. Hyperventilation and exercise decrease and increase the concentration of free calcium, respectively, because of changes in serum Both, serum free calcium and calcium... 

Major surgery with prolonged immobilization or any surgery on the legs Over 35 years old and currently a heavy smoker (20 or more cigarettes a day) Hypertension, 160+ mmHg/100+ mmHgor with vascular disease ... 

A variety of factors including low-fiber diets, drugs (e.g., anticholinergics, antacids or narcotics), prolonged immobilization and abdominal surgery cause constipation. 

Causes of rhabdomyolysis include prolonged immobilization on a hard surface, excessive seizures or muscular hyperactivity, hyperthermia, or direct cytotoxic effects of the drug or toxin (eg, carbon monoxide, colchicine. Amanita phalloides mushrooms, and some snake venoms). 

Kobayashi K, Shimoyama K, Nakamura K et al (2005) Percutaneous vertebroplasty immediately relieves pain of osteoporotic vertebral compression fractures and prevents prolonged immobilization of patients. Eur Radiol 15 360-367... 

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