Hypoxia (medical)
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}} Hypoxia is a pathological condition in which the body as a whole (generalized hypoxia) or region of the body (tissue hypoxia) is deprived of adequate oxygen supply. Hypoxia in which there is complete deprivation of oxygen supply is referred to as anoxia.
Hypoxia is often associated with high altitudes, where it is called altitude sickness. Hypoxia can also occur while diving underwater, especially with closed-circuit rebreather systems that control the amount of oxygen in the air breathed in.
Symptoms of generalized hypoxia depend on its severity and speed of onset. They include headaches, fatigue, shortness of breath, nausea, unsteadiness, and sometimes even seizures and coma. Severe hypoxia induces a blue discoloration of the skin (deoxygenated blood cells lose their bright red color in favor of a dark blue/red color).
Categories of hypoxia
- Cerebral hypoxia in which the brain is deprived of oxygen despite normal blood flow.
- Cerebral ischemia which causes hypoxia in the brain by impeding blood flow
- Hypoxic hypoxia when there's an inadequate supply of oxygen (as caused by high altitudes).
- Anemic hypoxia in which arterial oxygen pressure is normal, but total oxygen content of the blood is reduced.
- Hypemic Hypoxia when there's an inability of the blood to carry oxygen.
- Intrauterine hypoxia which is an unchallenged cause of perinatal death
- Ischemic, or stagnant hypoxia in which blood flow to the tissues is not adequate.
- Histotoxic hypoxia in which quantity of oxygen reaching the cells is normal, but the cells are unable to effectively use the oxygen.
See also
de:Hypoxie es:Hipoxia eo:Hipoksio fr:Hypoxie nl:Hypoxie (medisch) ru:Гипоксия