Combined traumatic brain injury and hemorrhagic shock in ferrets leads to structural, neurochemical, and functional impairments

Development of multisensory processing in ferret parietal cortex

It is well known that the nervous system adjusts itself to its environment during development. Although a great deal of effort has been directed towards understanding the developmental processes of the individual sensory systems (e.g., vision, hearing, etc.), only one major study has examined the maturation of multisensory processing in cortical neurons. Therefore, the present investigation sought to evaluate multisensory development in a different cortical region and species. Using multiple single-unit recordings in anaesthetised ferrets (n = 18) of different ages (from postnatal day 80 to 300), we studied the responses of neurons from the rostral posterior parietal (PPr) area to presentations of visual, tactile and combined visual-tactile stimulation. The results showed that multisensory neurons were infrequent at the youngest ages (pre-pubertal) and progressively increased through the later ages. Significant response changes that result from multisensory stimulation (defined as multisensory integration [MSI]) were observed in post-pubertal adolescent animals, and the magnitude of these integrated responses also increased across this age group. Furthermore, non-significant multisensory response changes were progressively increased in adolescent animals. Collectively, at the population level, MSI was observed to shift from primarily suppressive levels in infants to increasingly higher levels in later stages. These data indicate that, like the unisensory systems from which it is derived, multisensory processing shows developmental changes whose specific time course may be regionally and species-dependent.

Immunopathological Alterations after Blast Injury and Hemorrhage in a Swine Model of Prolonged Damage Control Resuscitation

Trauma-related hemorrhagic shock (HS) remains a leading cause of death among military and civilian trauma patients. We have previously shown that administration of complement and HMGB1 inhibitors attenuate morbidity and mortality 24 h after injury in a rat model of blast injury (BI) and HS. To further validate these results, this study aimed to develop a swine model and evaluate BI+HS-induced pathophysiology. Anesthetized Yucatan minipigs underwent combined BI and volume-controlled hemorrhage. After 30 min of shock, animals received an intravenous bolus of PlasmaLyte A and a continuous PlasmaLyte A infusion. The survival rate was 80% (4/5), and the non-survivor expired 72 min post-BI. Circulating organ-functional biomarkers, inflammatory biomarkers, histopathological evaluation, and CT scans indicated evidence of multiple-organ damage, systemic innate immunological activation, and local tissue inflammation in the injured animals. Interestingly, a rapid and dramatic increase in plasma levels of HMGB1 and C3a and markedly early myocarditis and encephalitis were associated with early death post-BI+HS. This study suggests that this model reflects the immunopathological alterations of polytrauma in humans during shock and prolonged damage control resuscitation. This experimental protocol could be helpful in the assessment of immunological damage control resuscitation approaches during the prolonged care of warfighters.

Vascular headache an traumatic brain injury

In a medical emergency, the most urgent patients at significant risk of death are those witha cerebrovascular accident and those with traumatic brain injury. Many are admitted withdiminished conscience status (coma) and focal neurological deficits. In the evaluation ofthese patients, neuroimaging is indispensable in order to identify the type of lesion andthe location of the brain where it is located.In the case of stroke, we can subdivide it into hemorrhagic and ischemic. Among hemorrhagic hemorrhages, we can mention (1) spontaneous intracerebral hematomasand (2) hemorrhages due to rupture of an intracranial aneurysm, with subarachnoidhemorrhage leading.Patients with head trauma are critical; even those who arrive at the hospital alert andoriented can decrease their level of consciousness in a few hours due to an intracranialhematoma, edema, or cerebral contusion.Thus, the availability of performing neuroimaging evaluations, using computed tomography and magnetic resonance imaging, or even digital angiography, is vital for continuoussupervision of this type of patient. The exams often require repetition several times due tothe rate of evolution of vascular lesions and after head trauma.A warning sign in these types of patients is headache. In the intracranial aneurysmal rupture, we classically have the thunderclap headache, an explosive, sudden pain mentionedas the worst pain the individual has suffered in his or her life. The pericranium and someintracranial structures are sensitive to nociceptive stimuli, such as the dura mater, largearteries, and venous sinuses. The brain is relatively insensitive to painful stimuli.This narrative review aims to inform the importance of neuroimaging assessment of patients with stroke and traumatic brain injury in an emergency department. In conclusion,a neuroimaging evaluation is paramount in addition to a neurological and physicalexamination of the critically ill patient with cerebrovascular disease or who has suffereda traumatic brain injury