What is ischemia?

What is ischemia?

• A. A condition resulting from insufficient blood flow to tissues, leading to tissue damage.
• B. Excessive blood flow causing swelling.
• C. An autoimmune attack on blood vessels.
• D. A condition of venous congestion without tissue damage.

Answer: (A)

Ischemia means reduced blood flow to a tissue, so the delivery of oxygen and nutrients falls short of what the cells need. When perfusion is lowered, cells switch to less efficient anaerobic metabolism, lose energy, and can accumulate damaging byproducts like lactic acid. If blood flow isn’t restored, the lack of oxygen and nutrients leads to cellular injury and, over time, tissue damage or death. This is exactly what the option describing insufficient blood supply to tissues with consequent tissue damage conveys. The other ideas describe different situations: too much blood flow (hyperemia/edema), an autoimmune attack on vessels (vasculitis), or venous congestion without ischemia.

Ischemia means reduced blood flow to a tissue, so the delivery of oxygen and nutrients falls short of what the cells need. When perfusion is lowered, cells switch to less efficient anaerobic metabolism, lose energy, and can accumulate damaging byproducts like lactic acid. If blood flow isn’t restored, the lack of oxygen and nutrients leads to cellular injury and, over time, tissue damage or death. This is exactly what the option describing insufficient blood supply to tissues with consequent tissue damage conveys. The other ideas describe different situations: too much blood flow (hyperemia/edema), an autoimmune attack on vessels (vasculitis), or venous congestion without ischemia.