The lower limit of reactivity as a potential individualised cerebral perfusion pressure target in traumatic brain injury: a CENTER-TBI high-resolution sub-study analysis
Erta Beqiri,
Frederick A. Zeiler,
Ari Ercole,
Michal M. Placek,
Jeanette Tas,
Joseph Donnelly,
Marcel J. H. Aries,
Peter J. Hutchinson,
David Menon,
Nino Stocchetti,
Marek Czosnyka,
Peter Smielewski,
CENTER-TBI HR ICU participants and investigators
Affiliations
Erta Beqiri
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge
Frederick A. Zeiler
Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba
Ari Ercole
Division of Anaesthesia, Department of Medicine, University of Cambridge
Michal M. Placek
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge
Jeanette Tas
School for Mental Health and Neuroscience (MHeNS), University Maastricht
Joseph Donnelly
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge
Marcel J. H. Aries
School for Mental Health and Neuroscience (MHeNS), University Maastricht
Peter J. Hutchinson
Division of Neurosurgery, Department of Clinical Neurosciences, Addenbrooke’s Hospital and University of Cambridge
David Menon
Division of Anaesthesia, Department of Medicine, University of Cambridge
Nino Stocchetti
Neuroscience Intensive Care Unit, Department of Anaesthesia and Critical Care, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico
Marek Czosnyka
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge
Peter Smielewski
Brain Physics Laboratory, Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge
Abstract Background A previous retrospective single-centre study suggested that the percentage of time spent with cerebral perfusion pressure (CPP) below the individual lower limit of reactivity (LLR) is associated with mortality in traumatic brain injury (TBI) patients. We aim to validate this in a large multicentre cohort. Methods Recordings from 171 TBI patients from the high-resolution cohort of the CENTER-TBI study were processed with ICM+ software. We derived LLR as a time trend of CPP at a level for which the pressure reactivity index (PRx) indicates impaired cerebrovascular reactivity with low CPP. The relationship with mortality was assessed with Mann-U test (first 7-day period), Kruskal–Wallis (daily analysis for 7 days), univariate and multivariate logistic regression models. AUCs (CI 95%) were calculated and compared using DeLong’s test. Results Average LLR over the first 7 days was above 60 mmHg in 48% of patients. %time with CPP < LLR could predict mortality (AUC 0.73, p = < 0.001). This association becomes significant starting from the third day post injury. The relationship was maintained when correcting for IMPACT covariates or for high ICP. Conclusions Using a multicentre cohort, we confirmed that CPP below LLR was associated with mortality during the first seven days post injury.
