In medicine, ischemia (Greek ισχαιμία, isch-'s restriction, hema or haema's blood)'s a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia. Mechanism Rather than in hypoxia, a more general term denoting a shortage of oxygen (usually a result of lack of oxygen in the air being breathed), ischemia's an absolute or relative shortage of the… (More on Ischemia)