What can trigger ischaemic injury?

Ischaemic injury occurs when there is a reduced blood supply to a tissue, leading to a lack of oxygen and nutrients necessary for cellular metabolism and function. This condition can result in cell death and tissue damage. Blood flow restriction is the primary trigger for ischaemic injury, as it directly compromises the delivery of oxygen and essential nutrients to the affected area.

When blood flow is restricted—whether due to a blockage in the blood vessels, constriction, or any factors that impair circulation—the cells in the tissue suffer from hypoxia (low oxygen levels) and can no longer maintain normal physiological processes. If the blood flow is not restored, the affected tissue can become irreversibly damaged, leading to conditions such as myocardial infarction (heart attack) or stroke.

While infection, physical trauma, and chemical exposure can also lead to injury in tissues, they do not directly cause ischaemic injury in the same manner. Infections may lead to inflammation and subsequent changes in blood flow, trauma can disrupt blood vessels but is not the primary mechanism of ischaemia, and chemical exposure can damage tissues through different pathways. Understanding that ischaemic injury is fundamentally tied to the availability and proper circulation of blood helps clarify why blood flow restriction is the correct answer