Editing Hypoxia (medicine) (section)

====Localized hypoxia====
{{see also|Ischemia}}{{anchor|Local hypoxia}}
[[File:Ischemia.JPG |thumb|Vascular ischemia of the toes with characteristic cyanosis]]
Hypoxia that is localized to a region of the body, such as an organ or a limb. is usually the consequence of [[ischemia]], the reduced perfusion to that organ or limb, and may not necessarily be associated with general hypoxemia. A locally reduced perfusion is generally caused by an increased resistance to flow through the blood vessels of the affected area.

Ischemia is a restriction in blood supply to any tissue, muscle group, or organ, causing a shortage of oxygen.<ref name="Merck" /><ref name="auto" />  Ischemia is generally caused by problems with [[blood vessel]]s, with resultant damage to or dysfunction of tissue i.e. hypoxia and [[microvascular dysfunction]].<ref name="Zhai et al 2013" /><ref name="Perico et al 2004" /> It also means local hypoxia in a given part of a body sometimes resulting from [[vascular occlusion]] such as [[vasoconstriction]], [[thrombosis]], or [[embolism]]. Ischemia comprises not only insufficiency of oxygen, but also reduced availability of [[nutrient]]s and inadequate removal of [[metabolic waste]]s. Ischemia can be a partial (poor [[perfusion]]) or total blockage.

Compartment syndrome is a condition in which increased pressure within one of the body's [[Compartment (anatomy)|anatomical compartments]] results in insufficient blood supply to [[Tissue (biology)|tissue]] within that space.<ref name="PMH 2017" /><ref name="Peitzman et al 2008" /> There are two main types: [[Acute (medicine)|acute]] and [[Chronic (medicine)|chronic]].<ref name="PMH 2017" /> Compartments of the leg or arm are most commonly involved.<ref name="Ferri 2018" />

{{expand section| local trauma, [[edema]], [[allergic reactions]], etc.|date=December 2022}}

If tissue is not being perfused properly, it may feel cold and appear pale; if severe, hypoxia can result in [[cyanosis]], a blue discoloration of the skin. If hypoxia is very severe, a tissue may eventually become gangrenous.