Reperfuzaní

Reperfuzaní (reperfusión) is the restoration of blood flow to tissue that has suffered ischemia. It is a central concept in conditions such as acute myocardial infarction, ischemic stroke, kidney and liver injury, and organ transplantation. Reperfuzaní can occur spontaneously when a blocked vessel recanalizes or be achieved intentionally through medical interventions that restore perfusion, including thrombolysis, mechanical thrombectomy, angioplasty with stent placement, and surgical revascularization.

Physiologically, reperfusion reintroduces oxygen and nutrients to previously deprived tissue, enabling recovery. However, it can also cause reperfusion injury, driven by oxidative stress, calcium overload, inflammatory responses, endothelial dysfunction, and microvascular obstruction. These processes can worsen tissue damage if reperfusion is abrupt or excessive.

Clinically, the aim of reperfusion therapy is to salvage viable tissue and improve functional outcomes, particularly in the heart and brain. In myocardial infarction, timely reperfusion limits infarct size; in stroke, recanalization strategies aim to restore cerebral blood flow while balancing the risk of hemorrhagic transformation. Reperfusion is also relevant in organ transplantation, where controlled reperfusion occurs after cold preservation to reduce injury.

Management often includes strategies to mitigate reperfusion injury, such as ischemic preconditioning, controlled or gradual reperfusion, pharmacological agents to attenuate oxidative stress, temperature management, and novel conditioning techniques. The balance between rapid restoration of blood flow and minimizing reperfusion injury shapes clinical decisions and timing in acute care.