Search Results (3)

Traumatic brain injury (TBI) remains one of the leading causes of death. Because of the individual nature of the trauma (brain, circumstances and forces), humans experience individual TBIs. This makes it difficult to generalise therapies. Clinical management issues such as whether intracranial pressure (ICP), cerebral perfusion pressure (CPP) or decompressive craniectomy improve patient outcome remain partly unanswered. Experimental drug approaches for the treatment of secondary brain injury (SBI) have not found clinical application. The complex, cellular and molecular pathways of SBI remain incompletely understood, and there are insufficient experimental (animal) models that reflect the pathophysiology of human TBI to develop translational therapeutic approaches. Therefore, we investigated different injury patterns after acute subdural hematoma (ASDH) as TBI in a post-hoc approach to assess the impact on SBI in a long-term, human-sized porcine TBI animal model. Post-mortem brain tissue analysis, after ASDH, bilateral ICP, CPP, cerebral oxygenation and temperature monitoring, and biomarker analysis were performed. Extracerebral, intraparenchymal–extraventricular and intraventricular blood, combined with brainstem and basal ganglia injury, influenced the experiment and its outcome. Basal ganglia injury affects the duration of the experiment. Recognition of these different injury patterns is important for translational interpretation of results in this animal model of SBI after TBI. Full article

Background: The subject of this study is intraoperative hypotension during the evacuation of acute subdural haematoma (ASH). We examined the association between the decrease in intraoperative blood pressure (BP) after the induction of anaesthesia and the decrease in BP after opening the dura mater. The second aim of this study was to assess the relationship between preoperative hypertension and the emergence of an intraoperative drop in BP. Methods: This was a retrospective cohort study on adult patients undergoing emergency craniotomy due to ASH. In total, 165 medical records from a 2-year period were analysed. The patients were divided into two groups: high blood pressure (HBP) (n = 89) and normal blood pressure (NBP) (n = 76). The HBP group included patients with hypertension in the preoperative period (systolic blood pressure (SBP) > 150 mmHg). The NBP group included patients with an SBP between 90 and 150 mmHg. Results: We observed a significant drop in blood pressure in two operational periods: after the induction of anaesthesia and after opening the dura mater. A highly relevant positive correlation was noted between the decrease in SBP after anaesthesia induction and the opening of the dura mater (p < 0.001). In the HBP group, after opening the dura mater, there was a 44% SBP decrease from the baseline value. Conclusions: The reduction in BP after the induction of anaesthesia is a predictor of a subsequent drop in BP after opening the dura mater during urgent surgery due to ASH. Patients with hypertension in the preoperative period of ASH tend to have a greater intraoperative drop in BP and worse outcomes. Full article

Traumatic brain injury (TBI) is a serious global health issue, leading to serious disabilities. One type of TBI is acute subdural haematoma (ASDH), which occurs when a bridging vein ruptures. Many numerical models of these structures, mainly based on the finite element method, have been developed. However, most rely on linear elasticity (without validation) and others on simplifications at the geometrical level. An example of the latter is the assumption of a regular cylinder with a constant radius, or the geometry of the vein acquired from medical images. Unfortunately, these do not replicate the real conditions of a mechanical tensile test. In this work, the main goal is to evaluate the influence of the vein’s geometry in its mechanical behaviour under tensile loading, simulating the real conditions of experimental tests. The second goal is to implement a hyperelastic model of the bridging veins where it would be possible to observe its non-linear elastic behaviour. The results of the developed finite element models were compared to experimental data available in the literature and other models. It was possible to conclude that the geometry of the vein structure influences the tensile stress–strain curve, which means that flattened specimens should be modelled when validating constitutive models for bridging veins. Additionally, the implementation of hyperelastic material models has been verified, highlighting the potential application of the Marlow and reduced polynomial (of fourth and sixth orders) constitutive models. Full article