Acta neurochirurgica. Supplement
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Acta Neurochir. Suppl. · Jan 2020
Spreading Depolarization during the Acute Stage of Experimental Subarachnoid Hemorrhage in Mice.
Spreading depolarization (SD) has been suggested as a pathomechanism for delayed cerebral ischemia after subarachnoid hemorrhage (SAH). However, the role of SD during the acute phase of SAH is still unclear. The objective of this study was to investigate (a) the occurrence of SD with intrinsic optical signal (IOS) imaging, (b) the effect of ketamine on SD, and (c) the resulting brain edema (brain water content (BWC)) during the acute stage of experimental SAH in mice. ⋯ These results demonstrate that SD occurs with a high incidence during the acute stage of SAH. SDs are heterogeneous in incidence, origination, and propagation. It remains unclear whether ketamine effects on SD may be viewed as therapeutically beneficial after SAH.
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Acta Neurochir. Suppl. · Jan 2018
Non-invasive Intracranial Pressure Assessment in Brain Injured Patients Using Ultrasound-Based Methods.
Non-invasive measurement of intracranial pressure (ICP) can be invaluable in the management of critically ill patients. Invasive measurement of ICP remains the "gold standard" and should be performed when clinical indications are met, but it is invasive and brings some risks. In this project, we aim to validate the non-invasive ICP (nICP) assessment models based on arterious and venous transcranial Doppler ultrasonography (TCD) and optic nerve sheath diameter (ONSD). ⋯ Our results demonstrate that among the non-invasive methods studied, ONSD showed the best accuracy in the detection of ICP.
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Acta Neurochir. Suppl. · Jan 2018
Pressure Reactivity-Based Optimal Cerebral Perfusion Pressure in a Traumatic Brain Injury Cohort.
Retrospective data from patients with severe traumatic brain injury (TBI) indicate that deviation from the continuously calculated pressure reactivity-based "optimal" cerebral perfusion pressure (CPPopt) is associated with worse patient outcome. The objective of this study was to assess the relationship between prospectively collected CPPopt data and patient outcome after TBI. ⋯ In a recent cohort of patients with severe TBI, the time spent with a CPP below the CPPopt-derived LLR is related to mortality. Despite aggressive CPP- and ICP-oriented therapies, TBI patients with a fatal outcome spend a significant amount of time with a CPP below their individualised CPPopt, indicating a possible therapeutic target.
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Acta Neurochir. Suppl. · Jan 2018
Visualizing Cerebrovascular Autoregulation Insults and Their Association with Outcome in Adult and Paediatric Traumatic Brain Injury.
The aim of this study is to assess visually the impact of duration and intensity of cerebrovascular autoregulation insults on 6-month neurological outcome in severe traumatic brain injury. ⋯ The colour-coded plots indicate that cerebrovascular autoregulation is disturbed in a dynamic manner, such that duration and intensity play a role in the determination of a zone associated with better neurological outcome.
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Acta Neurochir. Suppl. · Jan 2018
Occurrence of CPPopt Values in Uncorrelated ICP and ABP Time Series.
Optimal cerebral perfusion pressure (CPPopt) is a concept that uses the pressure reactivity (PRx)-CPP relationship over a given period to find a value of CPP at which PRx shows best autoregulation. It has been proposed that this relationship be modelled by a U-shaped curve, where the minimum is interpreted as being the CPP value that corresponds to the strongest autoregulation. Owing to the nature of the calculation and the signals involved in it, the occurrence of CPPopt curves generated by non-physiological variations of intracranial pressure (ICP) and arterial blood pressure (ABP), termed here "false positives", is possible. Such random occurrences would artificially increase the yield of CPPopt values and decrease the reliability of the methodology.In this work, we studied the probability of the random occurrence of false-positives and we compared the effect of the parameters used for CPPopt calculation on this probability. ⋯ This value can be minimised by tuning some of the calculation parameters, such as increasing the calculation window and increasing the minimum PRx span accepted on the curve.