Intercerebral autoregulation index consistency in the derivation of CPPopt, MAPopt, and BISopt in humans: A scoping...

The optimization of cerebral perfusion and sedation using autoregulation-derived physiologic targets such as optimal cerebral perfusion pressure (CPPopt), optimal mean arterial pressure (MAPopt), and optimal bispectral index (BISopt) has emerged as a promising strategy in neurocritical and perioperative care. However, the reliability and comparability of these optimal (Opt) parameters across different autoregulatory indices remain uncertain. This paper systematically reviews and synthesizes literature comparing CPPopt, MAPopt, and BISopt derived from invasive and noninvasive indices. Following PRISMA-ScR guidelines, studies directly comparing CPPopt, MAPopt, or BISopt from at least two indices were included. Ten studies compared CPPopt, mostly in traumatic brain injury, with mean values between 70 and 76 mmHg. Nine studies compared MAPopt, reporting strong correlations between transcranial doppler-, near-infrared spectroscopy-, and intracranial pressure-derived indices across populations, though limits of agreement were wide. One study compared BISopt across indices, showing internal consistency, while two cross-Opt studies found little correlation between BISopt and CPPopt or MAPopt. CPPopt and MAPopt appear physiologically robust across indices, supporting translational potential in both invasive and noninvasive settings. BISopt may represent a distinct optimization domain related to sedation rather than perfusion. Methodological heterogeneity and limited outcome validation remain barriers. Future work should emphasize standardization, multimodal integration, and outcome-driven trials.