Journal of neurotrauma
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Journal of neurotrauma · May 2012
Continuous monitoring of the Monro-Kellie doctrine: is it possible?
The Monro-Kellie doctrine describes the principle of homeostatic intracerebral volume regulation, which stipulates that the total volume of the parenchyma, cerebrospinal fluid, and blood remains constant. Hypothetically, a slow shift (e.g., brain edema development) in the irregular vasomotion-driven exchanges of these compartmental volumes may lead to increased intracranial hypertension. To evaluate this paradigm in a clinical setting and measure the processes involved in the regulation of systemic intracranial volume, we quantified cerebral blood flow velocity (CBFv) in the middle cerebral artery, arterial blood pressure (ABP), and intracranial pressure (ICP), in 238 brain-injured subjects. ⋯ The mortality rate is 5% when ICC is less than 0, and 43% when above 0.7. ICC above 0.7 was associated with terminally elevated ICP (chi-square p=0.026). We propose that the Monro-Kellie doctrine can be monitored in real time to illustrate the state of intracranial volume regulation.
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Journal of neurotrauma · May 2012
ReviewSocial function in children and adolescents after traumatic brain injury: a systematic review 1989-2011.
Clinical reports and case studies suggest that traumatic brain injury (TBI) can have significant social consequences, with social dysfunction reported to be the most debilitating problem for child and adolescent survivors. From a social neuroscience perspective, evidence suggests that social skills are not localized to a specific brain region, but are mediated by an integrated neural network. Many components of this network are susceptible to disruption in the context of TBI. ⋯ Despite these limitations, the weight of evidence confirmed an elevated risk of social impairment in the context of moderate and severe injury. While rarely examined, younger age at insult, pathology to frontal regions and the corpus callosum, and social disadvantage and family dysfunction may also increase the likelihood of social difficulties. More research is needed to obtain an accurate picture of social outcomes post-brain injury.
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Journal of neurotrauma · May 2012
Comparative StudyDifferential effects of voluntary and forced exercise on stress responses after traumatic brain injury.
Voluntary exercise increases levels of brain-derived neurotrophic factor (BDNF) after traumatic brain injury (TBI) when it occurs during a delayed time window. In contrast, acute post-TBI exercise does not increase BDNF. It is well known that increases in glucocorticoids suppress levels of BDNF. ⋯ Forced exercise did not increase levels of BDNF in any group. It did, however, decrease hippocampal glucocorticoid receptors in the control group. The results suggest that exercise regimens with strong stress responses may not be beneficial during the early post-injury period.
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Journal of neurotrauma · May 2012
Comparative StudyPrognostic value of diffusion tensor imaging parameters in severe traumatic brain injury.
Diffusion tensor imaging (DTI) has recently emerged as a useful tool for assessing traumatic brain injury (TBI). In this study, the prognostic value of the relationship between DTI measures and the clinical status of severe TBI patients, both at the time of magnetic resonance imaging (MRI), and their discharge to acute TBI rehabilitation, was assessed. Patients (n=59) admitted to the trauma center with severe closed head injuries were retrospectively evaluated after approval from the institution's institutional review board, to determine the prognostic value of DTI measures. ⋯ The inclusion of regional and global DTI measures improved the accuracy of prognostic models, when adjusted for admission GCS score and age (p<0.05). Whole brain white matter and regional DTI measures are sensitive markers of TBI, and correlate with neurological status both at MRI and discharge to rehabilitation. The addition of DTI measures adjusted for age, gender, and admission GCS score significantly improved prognostic models.
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Journal of neurotrauma · May 2012
Paroxysmal sympathetic hyperactivity after traumatic brain injury: clinical and prognostic implications.
A proportion of patients surviving severe traumatic brain injury (TBI) have symptoms suggestive of excessive sympathetic discharge, here termed paroxysmal sympathetic hyperactivity (PSH). The goals of this study were: (1) to describe the clinical associations and radiological findings of PSH, its incidence, and features in subjects with severe TBI in the intensive care unit (ICU); (2) to investigate the potential role of increased intracranial pressure in the pathogenesis of PSH; and (3) to determine the prognostic influence of PSH during the ICU stay, on discharge from the ICU, and at 12 months post-injury. A prospective cohort study was undertaken of all ICU admissions with severe TBI older than 14 years over an 18-month period. ⋯ At 1 year post-injury, 20% of this group demonstrated ongoing PSH episodes. Over 18 months, 10.1% of admissions following severe TBI demonstrated PSH features in ICU. Subjects with PSH had a longer ICU stay and higher rate of complications, although this did not appear to compromise their long-term neurological recovery.