Optimal Cerebral Perfusion Pressure Management at Bedside: A Single-Center Pilot Study

Area of Science:

• Neuroscience
• Critical Care Medicine
• Biomedical Engineering

Background:

• Current guidelines for acute traumatic brain injury (TBI) recommend specific cerebral perfusion pressure (CPP) and intracranial pressure targets.
• However, individual patient variability in cerebral autoregulation necessitates personalized treatment strategies.
• Assessing cerebral autoregulation at the bedside can optimize CPP-guided therapy.

Purpose of the Study:

• To evaluate staff compliance with a novel autoregulation-guided treatment (CPPopt) method.
• To determine the impact of CPPopt on patient outcomes in severe TBI.
• To assess the feasibility of continuous cerebrovascular reactivity (PRx) monitoring for treatment guidance.

Main Methods:

• A prospective pilot study involving adult patients with severe TBI in a Neurocritical Care Unit (NCCU).
• Continuous multimodal brain monitoring was employed, with CPPopt automatically estimated every minute using a 4-hour window of PRx data.
• Patients were managed with CPPopt targets when feasible; otherwise, standard guidelines were followed. Offline CPPopt calculations were performed using cerebral oximetry (COx-CPPopt), brain tissue oxygenation (ORxs-CPPopt), and cerebral blood flow (CBFx-CPPopt).

Main Results:

• Eighteen patients contributed 5,520 hours of monitoring data.
• A CPPopt U-shaped curve, indicating optimal autoregulation, was observed in 61% of patients.
• Real CPP significantly correlated with calculated CPPopt (r=0.83, p<0.0001). Preserved autoregulation correlated with better Glasgow Coma Scale scores and outcomes (p=0.01).
• A discrepancy >10 mmHg between real CPP and CPPopt was associated with adverse outcomes (p=0.04). COx-CPPopt showed the lowest bias (-0.1 mmHg).

Conclusions:

• Bedside management of CPP guided by cerebrovascular pressure reactivity (CPPopt) is feasible.
• Significant deviations from CPPopt are associated with adverse outcomes in TBI patients.
• The non-invasive COx-CPPopt method using NIRS warrants further investigation for clinical application.