HYPOXIA

An inadequate supply of oxygen to the tissues.

Temporary hypoxia may result from strenuous exercise. More serious causes are reduced blood flow to a part of your body and severe anaemia. A rare cause is carbon monoxide poisoning. Hypoxia also occurs in people at high altitude. Hypoxia in muscles forces the muscle cells to produce energy anaerobically, which leads to lactic acid accumulation and cramp.

In heart muscle it may cause angina. In the brain it causes confusion, dizziness and loss of coordination and may lead to unconsciousness and death if persistent.

Hypoxia can be assessed by using an oximeter to measure the oxygen concentration of blood in the tissues.

Severe cases of hypoxia may require oxygen therapy and artificial ventilation.