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The article presents patterns of use for mannitol and hypertonic saline in children with traumatic brain injury to assess any potential associations between hypertonic saline and mannitol use and patient demographic, injury, and treatment hospital characteristics and determine if the 2003 guidelines for severe pediatric traumatic brain injury affected clinical practice relating to osmolar therapy. Hypertonic saline and mannitol are utilized less in infants than older children.

Posttraumatic seizures and epilepsy are common in children experiencing traumatic brain injury and portend worse functional outcome. Unfortunately, the pathogenesis of pediatric posttraumatic seizures and epilepsy remains poorly understood, and no efficacious preventive therapy for post- traumatic epilepsy has been identified. This article reviews the epidemiology of pediatric posttraumatic seizures, discusses prominent putative mechanisms of posttraumatic epileptogenesis and highlights recent promising progress in experimental investigations of posttraumatic seizures and epilepsy. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Isoflurane improves outcome vs. fentanyl anesthesia, in experimental traumatic brain injury (TBI). We assessed the temporal profile of isoflurane neuroprotection and tested whether isoflurane confers benefit at the time of TBI. Adult, male rats were randomized to isoflurane (1%) or fentanyl (10 mcg/kg iv bolus then 50 mcg/kg/h) for 30 min pre-TBI. Anesthesia was discontinued, rats recovered to tail pinch, and TBI was delivered by controlled cortical impact. Immediately post-TBI, rats were randomized to 1 h of isoflurane, fentanyl, or no additional anesthesia, creating 6 anesthetic groups (isoflurane:isoflurane, isoflurane:fentanyl, isoflurane:none, fentanyl:isoflurane, fentanyl:fentanyl, fentanyl:none). Beam balance, beam walking, and Morris water maze (MWM) performances were assessed over post-trauma d1-20. Contusion volume and hippocampal survival were assessed on d21. Rats receiving isoflurane pre- and post-TBI exhibited better beam walking and MWM performances than rats treated with fentanyl pre- and any treatment post-TBI. All rats pretreated with isoflurane had better CA3 neuronal survival than rats receiving fentanyl pre- and post-TBI. In rats pretreated with fentanyl, post-traumatic isoflurane failed to affect function but improved CA3 neuronal survival vs. rats given fentanyl pre- and post-TBI. Post-traumatic isoflurane did not alter histopathological outcomes in rats pretreated with isoflurane. Rats receiving fentanyl pre- and post-TBI had the worst CA1 neuronal survival of all groups. Our data support isoflurane neuroprotection, even when used at the lowest feasible level before TBI (i.e., when discontinued with recovery to tail pinch immediately before injury). Investigators using isoflurane must consider its beneficial effects in the design and interpretation of experimental TBI research. [Copyright &y& Elsevier]

Despite common use of narcotics in the clinical management of severe traumatic brain injury (TBI), in experimental models rats treated with fentanyl have exhibited worse functional outcome and more CA1 hippocampal death than rats treated with standard isoflurane anesthesia. We hypothesized that greater post-traumatic excitotoxicity, reflected by cerebral glucose utilization (CMRglu), may account for detrimental effects of fentanyl vs. isoflurane. Rats were anesthetized with either isoflurane (1% by inhalation) or fentanyl (10 mcg/kg iv bolus then 50 mcg/kg/h infusion). 14C-deoxyglucose autoradiography was performed 45 min after controlled cortical impact (CCI) to left parietal cortex (n=4 per anesthetic group) or in uninjured rats after 45 min of anesthesia (n=3 per anesthetic group). Uninjured rats treated with fentanyl vs. isoflurane showed 35–45% higher CMRglu in all brain structures (p<0.05) except CA3. After TBI in rats treated with isoflurane, CMRglu increased significantly only in ipsilateral CA1 and ipsilateral parietal cortex (p<0.05 vs. isoflurane uninjured). Conversely, after TBI in rats treated with fentanyl, CMRglu increased markedly and bilaterally in CA1 and CA3 (p<0.05 vs. fentanyl uninjured), but not ipsilateral parietal cortex. In contralateral CA1, CMRglu was nearly two times greater after TBI in fentanyl vs. isoflurane treated rats (p<0.05). Hyperglycolysis was exacerbated in CA1 and CA3 hippocampus after TBI in rats treated with fentanyl vs. isoflurane anesthesia. This post-traumatic hyperglycolysis suggests greater excitotoxicity and concurs with reports of worse functional outcome and more CA1 hippocampal death after TBI with fentanyl vs. isoflurane anesthesia. [Copyright &y& Elsevier]

Summary: Electroconvulsive seizure thresholds were compared between adolescent and mature Sprague–Dawley, Wistar, and Fischer rats. All strains had similar hindbrain or forebrain seizure thresholds as adolescents. As adults, hindbrain or forebrain seizure thresholds were highest for Sprague–Dawley and lowest for Fischer rats. Conversely, limbic seizure thresholds during adolescence were highest for Fischer rats. Additional study is needed to better delineate strain and maturational effects on electroconvulsive seizure testing. [Copyright &y& Elsevier]

The author comments on a study by Jungner et al on the use of fluid resuscitation with albumin in a cat model of meningitis, published in this issue of "Critical Care Medicine." The author noted that benefits of albumin over saline, particularly after traumatic brain injury and hemorrhagic shock. However, the author asserted that the study did not consider direct pathogen-host interaction.