The following is a summary of “Visualization of Cerebral Pressure Autoregulatory Insults in Traumatic Brain Injury,” published in the April 2024 issue of Critical Care by Wettervik et al.
Researchers conducted a retrospective study to assess how severity and duration of abnormal blood pressure response (PRx) combined with deviation from optimal cerebral blood pressure target (∆CPPopt) affect outcomes in traumatic brain injury, also examining if PRx alters the relationship between intracranial pressure (ICP), CPP, and ∆CPPopt with outcome.
They monitored 553 traumatic brain injuries in the neurocritical care unit in Cambridge, UK. Each patient had ICP and arterial blood pressure (ABP) monitoring, and 6-month outcome data was assessed through the Glasgow Outcome Scale (GOS).
They correlated insult intensity (measured in mm Hg or as PRx coefficient) and duration (in minutes) of ICP, PRx, CPP, and ∆CPPopt with GOS and depicted them in heatmaps. In these representations, a shift from favorable to unfavorable outcomes occurred when PRx stayed positive for 30 minutes, especially at higher intensities. Similarly, a gradual transition from favorable to unfavorable outcome was observed in plots of ∆CPPopt when it dropped below –5 mm Hg for 30-minute periods, especially with more negative values. They also correlated the percentage of monitoring time with specific combinations of PRx with ICP, CPP, and ∆CPPopt with GOS and visualized them in heatmaps. In the combined PRx/ICP heatmap, ICP over 20 mm Hg and PRx over 0 were associated with unfavorable outcomes. In the PRx/CPP heatmap, CPP below 70 mm Hg and PRx above 0.2–0.4 correlated with adverse outcomes. In the PRx-/∆CPPopt heatmap, ∆CPPopt below 0 and PRx above 0.2–0.4 correlated with unfavorable outcomes.
Investigators concluded that abnormal PRx, ∆CPPopt, and their interaction with ICP and CPP influenced outcomes in traumatic brain injury.
Source: journals.lww.com/ccmjournal/abstract/9900/visualization_of_cerebral_pressure_autoregulatory.324.aspx
