Is a level of oxygen in the blood that is below normal.

It is something that is a below normal level of oxygen in the human blood. This happens unexpectedly in the arteries where there are low values under 60 mm Hg which predicts the requirement for oxygen. Mostly pulse readings fluctuate from 95 percent to 100 percent. This values which are below 90 are recognized as low level. Though oxygen level becomes low as well in the body due to lung diseases. Hypoxemia can cause brain damage and even death if not treated immediately.  

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