Patient-specific management of severe TBI depending on age and cerebrovascular autoregulation status

Abstract

Determination of proper choice of patient-specific management methodology is crucial for patients with traumatic brain injury (TBI). The treatment outcomes of TBI patients depend on cerebral blood flow autoregulation impairments which can also be affected by patients’ age, brain injury grade or pharmacological influences (anaesthetics, sedation, etc.). The objective of the prospective study was to explore the influence of various factors (dynamics of cerebrovascular autoregulation (CA) status, cerebral perfusion pressure (CPP) declination from optimal CPP value (ΔCPPopt), TBI severity, age, glucose level in blood, etc.) on the TBI patients' outcome. Multimodal ABP, ICP, CPP and CA monitoring of 81 TBI patients has been performed in Republic Vilnius University Hospital (Lithuania). ICM+ software (Cambridge, UK) was used for continuous CA status assessment by calculating Pressure Reactivity Index (PRx) and for identification of patient-specific optimal CPP (optCPP). The post-hoc analysis of associations between the patients' outcome and complex influence monitored parameters was performed by creating multifactorial model of predicting TBI patient's outcome and determining the most important factors affecting outcome. The multifactorial logistic regression model showed that the most significant factors affecting TBI patient's outcome are age, Glasgow Coma Scale (GCS), glucose level in blood serum samples (determined within 24 hours after admission), Helsinki CT (HCT) score and duration of longest CA impairment when PRx(t) > 0.5 within 24 hours after admission. The modelled accuracies for mortality and unfavorable outcome prediction were 82% and 86% respectively. The age > 45 years (P = 0.034, χ2 = 17.48) and HCT > 7 (P = 0.14, χ2 = 15.13) were found statistically significantly associated with unfavorable outcome or mortality. OptCPP-targeted management was found statistically significantly associated with better outcome for younger patients (age 0.36 and duration of LCAI > 100 min (P = 0.043, χ2 = 18.00) were found associated with mortality for younger patients group ( 0.26 (P = 0.005, χ2 = 7.80) and duration of LCAI > 61 min (P = 0.019, χ2 = 5.44) were founded associated with mortality for elderly patients group (> 45 years). The main factors affecting TBI treatment outcomes are patient's age, HCT, GCS, blood glucose level and the CA status during first day after patient admission. The optCPP-targeted patient-specific management is useful for stabilizing CA in severe TBI patients as well as for improving outcome for younger patients with age