ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Inflammation is an important part of the pathophysiology of traumatic brain injury. Although the central nervous system differs from the other organs because of the almost complete isolation from the blood stream mediated by the blood–brain barrier, the main steps characterizing the immune activation within the brain follow a scenario similar to that in other organs. The key players in these processes are the numerous immune mediators released within minutes of the primary injury. They guide a sequence of events including expression of adhesion molecules, cellular infiltration, and additional secretion of inflammatory molecules and growth factors, resulting in either regeneration or cell death. The question is this: to what extent is inflammation beneficial for the injured brain tissue, and how does it contribute to secondary brain damage and progressive neuronal loss? This review briefly reports recent evidence supporting the dual, the beneficial, or the deleterious role of neuroinflammation after traumatic brain injury.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Recently there has been much interest in the use of hypothermia in the management of the brain-injured patient and its effect on outcome. Most of these studies examine the use of hypothermia compared with normothermia of 37°C and have failed to demonstrate a benefit in the treatment groups, but what is normothermia in the brain-injured patient? Good epidemiologic evidence suggests that the vast majority of patients admitted to an ICU environment will develop a fever. The development of fever is clearly associated with a worse prognosis. There is now a better understanding of the possible mechanism of harm of fever and the side effects of cooling. Several treatment options for controlling temperature are discussed. Despite a sound physiologic argument for controlling fever in the brain-injured patient, there is no evidence that doing so will improve outcome.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The use of therapeutic moderate hypothermia for treating severe traumatic brain injury has been reported for more than 50 years. However, the most intense investigation of this treatment has occurred during the last 10 to 15 years. Virtually all preclinical studies have documented a robust treatment effect, not only in terms of reduced excitotoxicity and cerebral acidosis, but also in terms of histologic preservation and improved behavioral outcomes. Several single-center and small multicenter clinical trials conducted during the last decade also demonstrated benefit of early and late therapeutic hypothermia. However, a multicenter trial reported in February 2001 that included nearly 400 patients found no notable differences in neurologic outcomes in matched patients with head injuries who were treated with 48 hours of therapeutic moderate hypothermia compared with those kept at normal temperature. Findings from this study did suggest that rapid rewarming of patients with head injuries may be deleterious. A subgroup of young patients (less than 45 years of age) who were kept normovolemic showed a trend toward improved outcomes when treated with hypothermia. Current investigations, particularly in the preclinical arena, are focusing on combination therapy. To date, however, the addition of fibroblast growth factor, cyclosporine, or interleukin (IL)-10 to therapeutic moderate hypothermia has not been found to provide greater benefit than either therapy when used alone. Future investigations are aimed at further identifying the physiologic mechanisms responsible for secondary brain injury and ways in which other novel combination therapies may be expected to improve outcomes.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Cerebral monitoring of patients with acute intracranial disorders generally focuses on intracranial pressure and cerebral perfusion pressure monitoring. Over the past few years, several new techniques have become available for more detailed routine monitoring of cerebral oxygenation and metabolism. Brain tissue oxygen pressure measurement is increasingly being used for evaluation of cerebral oxygenation. This article discusses brain tissue oxygen pressure measurement in regards to its technical aspects, safety, reliability, and value relative to other techniques for evaluation of cerebral oxygenation. Published experimental and clinical data are considered, and the current status of the clinical use and indications of the technique are summarized. Monitoring may be performed in relatively undamaged parts of the brain or, preferably, in the penumbra region of an intracerebral lesion. Pathophysiologic evidence warrants targeting therapy for patients with traumatic brain injury and subarachnoid hemorrhage toward improvement of cerebral oxygenation guided by continuous monitoring of brain tissue oxygen tension.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Cerebral microdialysis is a relatively new technique for measuring the levels of brain extracellular chemicals, which to date has predominantly been used as a research tool. This review considers the technical aspects of microdialysis, the importance of the commonly measured chemicals, and the use of microdialysis to monitor patients with ischemic stroke, head injury, and subarachnoid hemorrhage. The advantages and disadvantages of microdialysis are discussed, as is its future potential.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Delayed vasospasm as a result of subarachnoid blood after rupture of a cerebral aneurysm is a major complication. It is seen in over half of patients and causes symptomatic ischemia in about one third. If left untreated, it leads to death or permanent deficits in over 20% of patients. The essential cause and the relative contribution of true muscle spasm and other changes in the vessel wall remain uncertain. The mainstays of treatment are careful maintenance of fluid balance, induced hypervolemia and hypertension, calcium antagonists, balloon or chemical angioplasty, and, in some centers, cisternal fibrinolytic drugs. Promising future lines of treatment include gene therapy, nitric oxide donors, magnesium, sustained release cisternal drugs, and several other drugs that are under experimental or clinical trial.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

According to European Brain Injury Consortium (EBIC) and American Brain Injury Consortium (ABIC) guidelines for severe head injuries, decompressive craniectomy is one therapeutic option for brain edema that does not respond to conventional therapeutic measures. As a result of the failure of all recently developed drugs to improve outcome in this patient group, decompressive craniectomy has experienced a revival during the last decade. Although class I studies of this subject are still lacking, there is strong evidence from prospective, uncontrolled trials that such an operation improves outcome in general and also has beneficial effects on various physiologic parameters that are known to be independent predictors for poor outcome. Whether this operation should be performed in a protocol-driven or in a prophylactic manner remains unclear. Decompressive craniectomy may, however, be the only method available in developing countries with limited ICU and monitoring resources. Prospectively controlled and randomized studies to definitively evaluate the effect of this old neurosurgical method on outcome in patients with traumatic brain injury (TBI) are forthcoming.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Ventilator-associated pneumonia usually originates from the patient's oropharyngeal microflora. In selective digestive decontamination, topical antibiotics are applied to the oropharynx and stomach for prevention of pneumonia and other infections, possibly reducing infection-related mortality. Selective digestive decontamination is also used for the prevention of gut-derived infections in acute necrotizing pancreatitis and liver transplantation. Despite numerous clinical trials, selective digestive decontamination remains controversial. Reduction of the incidence of pneumonia is accepted, but the extent of reduction is debated. Mortality was not reduced in most individual trials, but this finding was calculated in meta-analyses, especially for combined use of topical and systemic antibiotics in surgical ICU patients. Some investigators reported increased resistance and a shift to Gram-positive pathogens. Today, it appears thatselectivemeans not only selective suppression of pathogenic bacteria but also selection of appropriate groups of patients for underlying diseases and severity of illness, and selection of ICUs, where the endemic resistance patterns might allow the use of selective digestive decontamination at a relatively low risk for increased selection pressure.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Approximately 70% of the immune system is localized in the gastrointestinal tract: its glands, mucosa, and mucosa-associated lymphoid system. The system influences health conditions because it produces large amounts of important gastrointestinal secretions as rich as breast milk in health-supporting and disease-preventing factors, and because of its rich gastrointestinal flora. The intestine normally contains 10 times more microbes than there are eukaryotic cells in the entire body. The optimal function of these microbes depends on the supply of food destined for the colonic bacteria (fermentable fibers, complex proteins, gastrointestinal secretions). The consideration of these functions influences outcome. Unfortunately, the conditions (supply of drugs—especially antibiotics, and reduced supply of food—especially fruits and vegetables) in the modern ICU are extremely poor both for optimal gastrointestinal secretion and for flora and need more attention. To improve treatment, a supply of new and effective flora (probiotics) and food for the flora (prebiotics) is needed, from which numerous health-supporting products (synbiotics) will be produced and absorbed at the level of the mucosa, mainly in the lower gastrointestinal tract.

ISSN:1070-5295    

出版商:OVID    

年代:2002

数据来源: OVID