caa a22 4500 605509646 CHVBK 20210128100642.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s10877-014-9573-7 doi (NATIONALLICENCE)springer-10.1007/s10877-014-9573-7 An optimal frequency range for assessing the pressure reactivity index in patients with traumatic brain injury [Elektronische Daten] [Tim Howells, Ulf Johnson, Tomas McKelvey, Per Enblad] The objective of this study was to identify the optimal frequency range for computing the pressure reactivity index (PRx). PRx is a clinical method for assessing cerebral pressure autoregulation based on the correlation of spontaneous variations of arterial blood pressure (ABP) and intracranial pressure (ICP). Our hypothesis was that optimizing the methodology for computing PRx in this way could produce a more stable, reliable and clinically useful index of autoregulation status. The patients studied were a series of 131 traumatic brain injury patients. Pressure reactivity indices were computed in various frequency bands during the first 4days following injury using bandpass filtering of the input ABP and ICP signals. Patient outcome was assessed using the extended Glasgow Outcome Scale (GOSe). The optimization criterion was the strength of the correlation with GOSe of the mean index value over the first 4days following injury. Stability of the indices was measured as the mean absolute deviation of the minute by minute index value from 30-min moving averages. The optimal index frequency range for prediction of outcome was identified as 0.018-0.067Hz (oscillations with periods from 55 to 15s). The index based on this frequency range correlated with GOSe with ρ=−0.46 compared to −0.41 for standard PRx, and reduced the 30-min variation by 23%. Springer Science+Business Media New York, 2014 Cerebral pressure autoregulation nationallicence Intracranial pressure nationallicence Cerebral perfusion pressure nationallicence Clinical monitoring nationallicence Optimization nationallicence Howells Tim Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut Johnson Ulf Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut McKelvey Tomas Department of Signals and Systems, Chalmers University of Technology, Göteborg, Sweden aut Enblad Per Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut Journal of Clinical Monitoring and Computing Springer Netherlands 29/1(2015-02-01), 97-105 1387-1307 29:1<97 2015 29 10877 https://doi.org/10.1007/s10877-014-9573-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10877-014-9573-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Howells Tim Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut NATIONALLICENCE 700 1- Johnson Ulf Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut NATIONALLICENCE 700 1- McKelvey Tomas Department of Signals and Systems, Chalmers University of Technology, Göteborg, Sweden aut NATIONALLICENCE 700 1- Enblad Per Section of Neurosurgery, Department of Neuroscience, Uppsala University Hospital, 751 85, Uppsala, Sweden aut NATIONALLICENCE 773 0- Journal of Clinical Monitoring and Computing Springer Netherlands 29/1(2015-02-01), 97-105 1387-1307 29:1<97 2015 29 10877