Alternative continuous intracranial pressure-derived cerebrovascular reactivity metrics in traumatic brain injury: a scoping overview.

Non-PRx continuous ICP-based cerebrovascular reactivity metrics can be split into high-resolution and low-resolution measures. High-resolution indices include PAx, RAC, and PRx55-15, while low-resolution indices include L-PRx and LAx. The true role for these metrics beyond classic PRx remains unclear. Each displays situations where it may prove superior over PRx, given limitations with this currently widely accepted measure. Much future investigation into each of these alternative metrics is required prior to adoption into the clinical monitoring armamentarium in adult TBI.