Effects of Norepinephrine, Propofol, and Hemoglobin Concentration on Dynamic Measurements of Cerebrovascular Reactivity in Acute Brain Injury

Effects of treatment-associated variables on cerebrovascular autoregulation (CA) in acute brain injury patients remain unclear. As deficient CA is associated with worse outcomes and ideas about CA-steered management are emerging, this question relevant. We investigated effects norepinephrine propofol infusion rates hemoglobin concentration dynamic measurements reactivity as surrogate for CA. A retrospective analysis 91 traumatic (TBI) 13 stroke admitted to the intensive care unit (ICU) Leuven University Hospitals was performed. Low-resolution index (LAx) high-frequency pressure (PRx) were calculated reactivity. Data binned into 5-, 15-, 60-min intervals. Bivariate time-series using lagged cross-correlations after pre-whitening differencing. Linear mixed models evaluated age, gender, cardiovascular risk, comorbidity, Glasgow Coma Scale (GCS), pupil reactivity, type injury. Median dose norepinephrine, 7.8 ?g/kg/h (Q1 3.6-Q3 13.8), 3 mg/kg/h 1.9-Q3 4.3), 9.2 g·dL?1 8.2-Q3 10.5), respectively. Mean 24 lags close zero not significant all variables. No differences function GCS, found. Dynamic intracranial pressure–based injured affected by gradually adjusted or slow changes within typical ranges during ICU admission. Future trials reactivity–steered treatment impairment may have take these account.