Background and Goal of the study:
We have sought to validate our automated methodology for continuous updating of optimal cerebral perfusion pressure (CPPopt) estimations, based on monitoring of cerebrovascular pressure reactivity (PRx), in patients after severe traumatic head injury (TBI).
Retrospective collected data of TBI patients admitted at the Neurosciences critical care unit of a university hospital were analysed. Mean arterial pressure (MAP), intracranial pressure (ICP), and CPP were continuously recorded and PRx was calculated online. Outcome was assessed at 6 months.
A total of 327 TBI patients admitted between 2003 and 2009 with continuous monitoring of MAP and ICP. An automated curve fitting method was applied to determine CPP at the minimum value for PRx (CPPopt). Minute-by-minute time trends of CPPopt were created using a moving 4-hour window. Identification of CPPopt was on average feasible during 55% of the whole recording period. Patient outcome correlated with the continuously updated difference between CPP and CPPopt (χ2 = 45, P < 0.001). Higher mortality was associated with relative ‘hypoperfusion’ (CPP < CPPopt), severe disability with ‘hyperperfusion’ (CPP > CPPopt) while favorable outcome was associated with CPP close to the individualized CPPopt. Examining difference of CPP from fixed thresholds of 60 and 70 mmHg rendered much less robust relationships.
Conclusions and Discussion:
Real time trend of CPPopt could be calculated in each patient. Patients with a CPP close to CPPopt were more likely to achieve a favorable outcome than those whose mean CPP was widely different from CPPopt. CPP management to optimize cerebrovascular pressure reactivity should be subject of future clinical trials in TBI patients.
© 2012 European Society of Anaesthesiology