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Brain Insults (brain + insult)
Selected AbstractsRecommendation for a definition of acute symptomatic seizureEPILEPSIA, Issue 4 2010Ettore Beghi Summary Purpose:, To consider the definition of acute symptomatic seizures for epidemiological studies, and to refine the criteria used to distinguish these seizures from unprovoked seizures for specific etiologies. Methods:, Systematic review of the literature and of epidemiologic studies. Results:, An acute symptomatic seizure is defined as a clinical seizure occurring at the time of a systemic insult or in close temporal association with a documented brain insult. Suggestions are made to define acute symptomatic seizures as those events occurring within 1 week of stroke, traumatic brain injury, anoxic encephalopathy, or intracranial surgery; at first identification of subdural hematoma; at the presence of an active central nervous system (CNS) infection; or during an active phase of multiple sclerosis or other autoimmune diseases. In addition, a diagnosis of acute symptomatic seizure should be made in the presence of severe metabolic derangements (documented within 24 h by specific biochemical or hematologic abnormalities), drug or alcohol intoxication and withdrawal, or exposure to well-defined epileptogenic drugs. Discussion:, Acute symptomatic seizures must be distinguished from unprovoked seizures and separately categorized for epidemiologic purposes. These recommendations are based upon the best available data at the time of this report. Systematic studies should be undertaken to better define the associations in question, with special reference to metabolic and toxic insults, for which the time window for the occurrence of an acute symptomatic seizure and the absolute values for toxic and metabolic dysfunction still require a clear identification. [source] Brain Protection During Pediatric Cardiopulmonary BypassARTIFICIAL ORGANS, Issue 4 2010Xiaowei W. Su Abstract Improvements in peri- and postoperative surgical techniques have greatly improved outcomes for pediatric patients undergoing cardiopulmonary bypass (CPB) in the treatment of congenital heart defects (CHDs). With decreased mortality rates, the incidence of adverse neurological outcomes, comprising cognitive and speech impairments, motor deficits, and behavioral abnormalities, has increased in those patients surviving bypass. A number of mechanisms, including ischemia, reperfusion injury, hypothermia, inflammation, and hemodilution, contribute to brain insult, which is further confounded by unique challenges presented in the pediatric population. However, a number of brain monitoring and preventative techniques have been developed or are being currently evaluated in the practice of pediatric CPB. Monitoring techniques include electroencephalography, near-infrared as well as visible light spectroscopy, transcranial Doppler ultrasound, and emboli detection and classification quantitation. Preventative measures include hypothermic perfusion techniques such as deep hypothermic circulatory arrest, low-flow CPB, blood gas management, and pharmacologic prophylaxes, among others. The present review summarizes the principles of brain insult, neurodevelopmental abnormalities, monitoring techniques, methods of prevention, as well as preexisting morbidities and risk factors in pediatric CPB, with a focus on brain protection. Clinical and translational research is presented with the aim of determining methods that may optimize neurological outcomes post CPB and guiding further study. [source] Pursuing paradoxical proconvulsant prophylaxis for epileptogenesisEPILEPSIA, Issue 7 2009Caren Armstrong Summary There are essentially two potential treatment options for any acquired disorder: symptomatic or prophylactic. For acquired epilepsies that follow a variety of different brain insults, there remains a complete lack of prophylactic treatment options, whereas at the same time these epilepsies are notoriously resistant, once they have emerged, to symptomatic treatments with antiepileptic drugs. The development of prophylactic strategies is logistically challenging, both for basic researchers and clinicians. Nevertheless, cannabinoid-targeting drugs provide a very interesting example of a system within the central nervous system (CNS) that can have very different acute and long-term effects on hyperexcitability and seizures. In this review, we outline research on cannabinoids suggesting that although cannabinoid antagonists are acutely proconvulsant, they may have beneficial effects on long-term hyperexcitability following brain insults of multiple etiologies, making them promising candidates for further investigation as prophylactics against acquired epilepsy. We then discuss some of the implications of this finding on future attempts at prophylactic treatments, specifically, the very short window within which prevention may be possible, the possibility that traditional anticonvulsants may interfere with prophylactic strategies, and the importance of moving beyond anticonvulsants,even to proconvulsants,to find the ideal preventative strategy for acquired epilepsy. [source] On-line glucose and lactate monitoring in rat striatum: effect of malonate and correlation with histological damageJOURNAL OF NEUROCHEMISTRY, Issue 2003J. Skjoeth-Rasmussen Microdialysis of glucose, lactate and glycerol was performed to monitor brain insults and to predict brain injury in a rat model using the mitochondrial toxin malonate (5,100 mm). Striatal dialysates were analyzed off-line using a CMA 600 microdialysis analyzer or on-line using flow-injection analysis and biosensors for glucose and lactate. Histological damage was evaluated using stereological principles. Lactate (baseline ca. 1 mm) was dose-dependently increased, reaching a maximum of five- to six-fold increase, whereas glucose (baseline 1,2 mm) was decreased (>50%) by malonate >20 mm. These changes were reversible upon perfusion with normal Ringer's. Transient increases in glycerol (four- to eight-fold) were only observed in some rats, and were not dose-dependent. Histological damage was related to the perfused malonate concentration, but was not significantly correlated with lactate or glycerol changes. [source] Management of critically ill children with traumatic brain injuryPEDIATRIC ANESTHESIA, Issue 6 2008GILLES A. ORLIAGUET MD PhD Summary The management of critically ill children with traumatic brain injury (TBI) requires a precise assessment of the brain lesions but also of potentially associated extra-cranial injuries. Children with severe TBI should be treated in a pediatric trauma center, if possible. Initial assessment relies mainly upon clinical examination, trans-cranial Doppler ultrasonography and body CT scan. Neurosurgical operations are rarely necessary in these patients, except in the case of a compressive subdural or epidural hematoma. On the other hand, one of the major goals of resuscitation in these children is aimed at protecting against secondary brain insults (SBI). SBI are mainly because of systemic hypotension, hypoxia, hypercarbia, anemia and hyperglycemia. Cerebral perfusion pressure (CPP = mean arterial blood pressure , intracranial pressure: ICP) should be monitored and optimized as soon as possible, taking into account age-related differences in optimal CPP goals. Different general maneuvers must be applied in these patients early during their treatment (control of fever, avoidance of jugular venous outflow obstruction, maintenance of adequate arterial oxygenation, normocarbia, sedation,analgesia and normovolemia). In the case of increased ICP and/or decreased CPP, first-tier ICP-specific treatments may be implemented, including cerebrospinal fluid drainage, if possible, osmotic therapy and moderate hyperventilation. In the case of refractory intracranial hypertension, second-tier therapy (profound hyperventilation with PaCO2 < 35 mmHg, high-dose barbiturates, moderate hypothermia, decompressive craniectomy) may be introduced, after a new cerebral CT scan. [source] |