Temporary Intraoperative Cerebral Blood Flow Reduction to Facilitate Neurovascular Procedures

Temporary blood flow reduction is essential in the management of complex neurovascular lesions in both open and endovascular settings. This focused review examines the four principal techniques commonly used to achieve flow reduction for neurovascular procedures. Deep hypothermic circulatory arrest (DHCA) has largely become obsolete in recent years due to significant perioperative morbidity and the emergence of less invasive flow reduction strategies. Intravenous adenosine remains a popular option since it is readily available in the perioperative setting, though the hemodynamic response may be unpredictable because of interindividual dose-response variability. Rapid ventricular pacing (RVP) provides controlled, predictable flow reduction but requires advanced procedural planning. Endovascular balloon-assisted occlusion provides localized control in anatomically challenging areas under a hybrid neurosurgical-endovascular approach. To date, no single technique has demonstrated superiority over another, and the optimal strategy should be individualized based on lesion characteristics, institutional expertise, and available resources. Future research should focus on potential neuroprotective strategies during flow reduction and further characterize the safety and efficacy profiles of various flow reduction techniques through prospective cohort studies.