Optimal Cerebral Perfusion Pressure in Centers With Different Treatment Protocols

Area of Science:

• Neurocritical care
• Traumatic Brain Injury (TBI) management
• Cerebral Autoregulation

Background:

• Management of traumatic brain injury (TBI) often involves targeting cerebral perfusion pressure (CPP).
• However, optimal CPP targets and the use of vasopressors vary across neurocritical care units.
• These variations may impact the estimation of CPP that best supports cerebral autoregulation.

Purpose of the Study:

• To investigate whether differing institutional policies on CPP targets and vasopressor use affect the estimation of optimal cerebral perfusion pressure (oCPP).
• oCPP is defined as the CPP level that optimizes cerebral autoregulation strength.
• This study aims to understand the influence of these policies on oCPP estimation in TBI patients.

Main Methods:

• Retrospective analysis of prospectively collected data from 104 TBI patients across three university hospital neurocritical care units (Cambridge, UK; Groningen, Netherlands; Uppsala, Sweden).
• Data included CPP measurements and institutional CPP targets, which varied (Groningen: ≥50 to <70 mmHg; Uppsala: ≥60 mmHg; Cambridge: ≥60 or preferably ≥70 mmHg).
• Optimal cerebral perfusion pressure (oCPP) was calculated using established methods and software; analysis focused on CPP relative to oCPP, including differences and monitoring time percentages.

Main Results:

• Despite protocol differences, median CPP in all centers exceeded 70 mmHg.
• The Uppsala cohort, with older patients, showed the highest CPP/oCPP difference, suggesting age positively correlates with this difference.
• oCPP was significantly lower in Groningen compared to Cambridge; summary oCPP curves could not be generated for Uppsala, potentially due to the older patient cohort.

Conclusions:

• Variations in institutional demographics (e.g., patient age) and treatment protocols (CPP targets) influence optimal cerebral perfusion pressure (oCPP) calculations.
• These factors must be considered when designing future clinical trials.
• Further research is needed to refine autoregulation-guided treatment strategies in traumatic brain injury.