23.4% Hypertonic Saline: A Tactical Option for the Management of Severe Traumatic Brain Injury With Impending or Ongoing Herniation.

There are limited options available to the combat medic for management of traumatic brain injury (TBI) with impending or ongoing herniation. Current pararescue and Tactical Combat Casualty Care (TCCC) guidelines prescribe a bolus of 3% or 5% hypertonic saline. However, this fluid bears a tactical burden of weight (~570g) and pack volume (~500cm3). Thus, 23.4% hypertonic saline is an attractive option, because it has a lighter weight (80g) and pack volume (55cm3), and it provides a similar osmotic load per dose. Current literature supports the use of 23.4% hypertonic saline in the management of acute TBI, and evidence indicates that it is safe to administer via peripheral and intraosseous cannulas. Current combat medic TBI treatment algorithms should be updated to include the use of 23.4% hypertonic saline as an alternative to 3% and 5% solutions, given its effectiveness and tactical advantages.

NeuroEthics and End of Life Care.

The emergency department is where the patient and potential ethical challenges are first encountered. Patients with acute neurologic illness introduce a unique set of dilemmas related to the pressure for ultra-early prognosis in the wake of rapidly advancing treatments. Many with neurologic injury are unable to provide autonomous consent, further complicating the picture, potentially asking uncertain surrogates to make quick decisions that may result in significant disability. The emergency department physician must take these ethical quandaries into account to provide standard of care treatment.

Gender differences in neural-behavioral response to self-observation during a novel fMRI social stress task.

UNLABELLED: The neural correlates of response to psychosocial stress and gender differences therein are difficult to model experimentally as this type of stressor is difficult to induce in a brain imaging environment. The Trier Social Stress Test (TSST), a behavioral paradigm that reliably induces moderate levels of stress was thus modified for the MRI environment. To determine the neurobehavioral basis of gender differences in response to observing oneself under social evaluative stress, 26 subjects (14 females) performed the TSST while being videotaped. During fMRI scanning, subjects were shown alternating video clips of two CONDITIONS: SELF or a same-sex OTHER performing the TSST. Subjects rated their stress level immediately after the video clips. GENDER differences in the [SELF-OTHER] contrast were analyzed. There was a GENDER×CONDITION interaction such that only women reported increased subjective stress during video feedback of their TSST session. A whole brain analysis (SELF vs. OTHER) showed activation in the bilateral insula, inferior, middle and superior frontal gyri. Greater recruitment was seen among males in some of these same areas in the context of significantly lower stress ratings. Activation of areas involved in inhibitory control and sensory awareness might contribute to the significantly lower stress ratings in males. Understanding these gender differences is relevant to disorders of stress and self-concept.

Memory ability and hippocampal volume in adolescents with prenatal drug exposure.

The objective of the present study was to examine the influence of prenatal drug exposure (PDE) on memory performance and supporting brain structures (i.e., hippocampus) during adolescence. To achieve this goal, declarative memory ability and hippocampal volume were examined in a well-characterized sample of 138 adolescents (76 with a history of PDE and 62 from a non-exposed comparison group recruited from the same community, mean age=14 years). Analyses were adjusted for: age at time of the assessments, gender, IQ, prenatal exposure to alcohol and tobacco, and indices of early childhood environment (i.e., caregiver depression, potential for child abuse, and number of caregiver changes through 7 years of age). Results revealed that adolescents with a history of PDE performed worse on the California Verbal Learning Test-Child Version (CVLT-C), and story recall from the Children's Memory Scale (CMS), and had larger hippocampal volumes, even after covariate adjustment. Hippocampal volume was negatively correlated with memory performance on the CVLT-C, with lower memory scores associated with larger volumes. These findings provide support for long-term effects of PDE on memory function and point to neural mechanisms that may underlie these outcomes.