Cerebral Perfusion Pressure in Severe Traumatic Brain Injury Survivors and Non-Survivors: A Meta-Analysis

Background: Severe traumatic brain injury (sTBI) is a leading cause of death and disability worldwide. Cerebral perfusion pressure (CPP), the difference between mean arterial and intracranial pressure, is crucial for maintaining cerebral blood flow. However, the optimal CPP threshold for improving outcomes remains uncertain. Objective: To identify CPP levels associated with favorable outcomes following sTBI through a systematic review and meta-analysis. Methods: Following PRISMA guidelines, we systematically searched PubMed, Scopus, and Web of Science up to February 2024 for studies involving adult sTBI patients admitted to intensive care units. Studies reporting CPP in relation to outcomes measured by the Glasgow Outcome Scale (GOS) were included. Pooled mean CPP differences between outcome groups were calculated using a random-effects model. Study quality was assessed using the Newcastle–Ottawa Scale, and evidence certainty was evaluated with GRADE. Results: Twenty-two studies with 2986 patients met inclusion criteria. Patients with good outcomes (GOS > 3) had higher CPP (77.5 mmHg; 95% CI: 73.8–81.2) than those with poor outcomes (67.2 mmHg; 95% CI: 60.4–74.1), with a mean difference of 10.01 mmHg (95% CI: 4.23–15.80; p < 0.05). Survivors also demonstrated higher CPP than non-survivors (mean difference 8.15 mmHg; 95% CI: 3.28–13.02). Evidence quality ranged from low to very low due to study heterogeneity. Conclusions: Higher CPP levels (~75–80 mmHg) are associated with better survival and functional outcomes after sTBI, supporting individualized, multimodal CPP management rather than a fixed 60 mmHg threshold.