Association Between Individualized Intracranial Pressure Thresholds and Long-Term Outcomes in Moderate-to-Severe TBI:...

Current neurocritical care relies on fixed, population-based intracranial pressure (ICP) thresholds, which fail to account for inter-individual variability or the dynamic nature of cerebral physiology. Individualized ICP (iICP) thresholds have emerged as a potential personalized alternative but have largely relied on complete recording periods, limiting their derivation to post-hoc calculations and preventing continuous real-time estimation. Recently, a novel algorithm capable of continuously deriving iICP was developed; however, this algorithm has not yet been validated beyond a single-center cohort, and its prognostic utility remains uncertain. Therefore, the goals of this study were to externally validate the performance of this continuous iICP algorithm and to evaluate the prognostic utility of continuously derived iICP compared with current guideline-based ICP thresholds. A retrospective multicenter study was conducted using high-resolution physiologic datasets from the CAHR-TBI collaborative. iICP was derived using the recently developed continuous iICP algorithm. Algorithm performance was externally validated by assessing derivation yields and associated quality metrics and comparing with those reported in the original study that introduced the algorithm. Outcome associations were evaluated using mean hourly dose of ICP above iICP and guideline-based thresholds. Logistic regression models were used to assess and compare prognostic performance, with discrimination quantified using optimism-corrected area under the receiver operating characteristic curve and added predictive value assessed using Nagelkerke's R2. Finally, intensity-duration heatmaps were generated to characterize the relationship between iICP-based insult burden and clinical outcomes. The continuous iICP algorithm demonstrated consistent performance across parameter settings compared with the original study, supporting its external validity. Select hybrid iICP configurations, defaulting to 20 mmHg or 22 mmHg during periods where iICP could not be identified, outperformed guideline-based ICP thresholds in prognostic models. Heatmap analyses demonstrated a graded relationship between iICP-defined insult burden and outcome, with greater burden of ICP above iICP associated with poorer outcomes. Overall, iICP represents a promising adjunct to conventional guideline-based ICP management in neurocritical care. The findings of this study suggest potential clinical benefit from iICP-supplemented ICP management; however, prospective randomized controlled trials will be required to determine whether such an approach translates into meaningful improvements in patient outcomes.