Ischemia

Ischemia
Other namesischaemia, ischæmia
Vascular ischemia of the toes with characteristic cyanosis
Pronunciation
SpecialtyVascular surgery

Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive).[3][4] Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue i.e. hypoxia and microvascular dysfunction.[5][6] It also implies local hypoxia in a part of a body resulting from constriction (such as vasoconstriction, thrombosis, or embolism).

Ischemia causes not only insufficiency of oxygen, but also reduced availability of nutrients and inadequate removal of metabolic wastes.[7] Ischemia can be partial (poor perfusion) or total blockage. The inadequate delivery of oxygenated blood to the organs must be resolved either by treating the cause of the inadequate delivery or reducing the oxygen demand of the system that needs it. For example, patients with myocardial ischemia have a decreased blood flow to the heart and are prescribed with medications that reduce chronotropic and inotropic effect to meet the new level of blood delivery supplied by the stenosed vasculature so that it is adequate.

  1. ^ OED 2nd edition, 1989.
  2. ^ Entry "ischemia" in Merriam-Webster Online Dictionary.
  3. ^ Merck & Co. Occlusive Peripheral Arterial Disease, The Merck Manual Home Health Handbook website, revised and updated March 2010. Retrieved March 4, 2012.
  4. ^ "Chronic Limb-Threatening Ischemia (CLTI) – Vascular Cures". Archived from the original on 2021-10-29. Retrieved 2021-10-27.
  5. ^ Zhai Y, Petrowsky H, Hong JC, et al: Ischaemia-reperfusion injury in liver transplantation—From bench to bedside. Nat Rev Gastroenterol Hepatol 2013; 10:79–89
  6. ^ Perico N, Cattaneo D, Sayegh MH, et al: Delayed graft function in kidney transplantation. Lancet 2004; 364:1814–1827
  7. ^ "Google Scholar". scholar.google.com. Retrieved 2024-08-26.