<unk>  is a clinical syndrome characterized by inadequate oxygenation and perfusion to supply the body's metabolic needs. There is simply a loss of sufficient blood pressure to generate an adequate pressure gradient to maintain tissue perfusion. This leads to a loss of oxygen supply and the deterioration of energy dependent processes at cellular level and lactic acidosis.<unk>  is a serious, life-threatening medical condition where insufficient blood flow reaches the body tissues. As the blood carries oxygen and nutrients around the body, reduced flow hinders the delivery of these components to the tissues, and can stop the tissues from functioning properly. The process of blood entering the tissues is called perfusion, so when perfusion is not occurring properly this is called a hypoperfusional state. The body has homeostatic mechanisms to compensate for hypoperfusion, but when these are overwhelmed, several physiological and metabolic derangements result.<unk>  should not be confused with the emotional state of<unk> , as the two are not related.  Medical<unk>  is a life-threatening medical emergency and one of the most common causes of death for critically-ill people.<unk>  can have a variety of effects, all with similar outcomes, but all relate to a problem with the body's circulatory system. For example,<unk>  may lead to hypoxia (a lack of oxygen in the body tissues) or cardiac arrest (the heart stopping).
Shock
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Axial skeleton
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