ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewDespite 25 years of randomized, controlled trials, the benefit of steroid administration to patients with traumatic brain injury is unproved. Traditionally, glucocorticoids have been used empirically to reduce inflammation and edema. However, it is becoming apparent that the mechanisms by which steroid molecules might act to improve recovery after traumatic brain injury are numerous.Recent findingsThe effects of steroid administration on the central nervous system are not uniform but depend on the population of neurons studied. Definite deleterious effects of steroid administration on neuronal survival have been described.SummaryThis review discusses why glucocorticoids might be effective, the considerable laboratory evidence supporting the use of 21-aminosteroids, and the potentially harmful effects of steroid molecules on the brain.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewTo provide an update on the progress of the multicenter, randomized, controlled trial of corticosteroids after significant head injury (CRASH).Recent findingsAfter a successful pilot phase, the main phase of the CRASH Trial began in March 2001. By June 2002, 107 hospitals from 31 countries were participating in the trial, and together had recruited 3000 patients. Nine hundred patients (30%) had mild head injury, 885 (30%) had moderate head injury, and 1215 (40%) had severe head injury. A total of 1941 (65%) patients were randomized within 3 hours of injury. Outcome at 2 weeks from injury was known for 2933 (98%) patients, of whom 557 (19%) died. At the time of writing, 6-month follow-up for the first 1500 patients was nearly complete. Vital status was known for 1429 (95%) of the 1500 patients, of whom 313 (22%) had died. Functional status based on the Glasgow Outcome Scale was known for 1391 (93%) of the 1500 patients: 22% were dead, 16% were severely disabled, 23% were moderately disabled, and 39% had made a good recovery.SummaryThe CRASH Trial is a randomized, placebo-controlled, multicenter trial of a 48-hour corticosteroid infusion after significant head injury and is now the largest head injury trial ever conducted. The efforts of the national coordinators have shown that it is possible to enroll and follow up very large numbers of head-injured patients.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThe goal of this article is to summarize very recent technologic advances in neurophysiologic monitoring and to illustrate their potential benefit to critical care medicine.Recent findingsSimplified, computer-processed electroencephalography devices now permit cost-effective, long-term critical care monitoring. They may be used alone to objectively assess sedation or coma level. In addition, these monitors serve as screening tools for more detailed electrophysiologic characterization of cortical dysfunction resulting from seizures, ischemia, or hypoxia. Somatosensory potentials broaden these capabilities to the entire neuraxis, whereas long-latency auditory evoked potentials facilitate measurement of changes in vigilance and cognition. Motor evoked potentials offer a sensitive and reliable method to determine the function of descending motor pathways in uncooperative or unresponsive patients. They may also yield a new measure of cortical excitability. New developments with transcranial Doppler ultrasonography promise noninvasive measures of cerebral perfusion pressure and particulate embolization. Near-infrared spectroscopy appears to enable noninvasive measurement of regional tissue oxygenation in both the brain and spinal cord.SummaryWhen used together, these continuous measures of synaptic function, cerebral perfusion, and oxygenation give the clinician a vast amount of otherwise unobtainable information regarding the functional status of the central nervous system.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThis review highlights recent advances in the critical care management of neuromuscular disease, particularly in the long-term management of chronic respiratory failure occurring as a consequence of neuromuscular disease.Recent findingsAlthough randomized clinical trial evidence of benefit is sparse, a large volume of nonrandomized clinical trial evidence has accumulated demonstrating that noninvasive positive pressure ventilation prolongs and improves quality of life in conditions such as Duchenne muscular dystrophy and motor neuron disease.SummaryImmunomodulatory treatments favorably modify the course of neuromuscular diseases such as Guillain-Barré syndrome, whereas long-term noninvasive positive pressure ventilation has transformed the outlook in previously untreatable conditions such as motor neuron disease and muscular dystrophies. The availability of long-term noninvasive positive pressure ventilation raises major medical, social, economic, and ethical issues that are increasingly being investigated and discussed.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewTo summarize new pathophysiologic insights and recent advances in the diagnosis and treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage.Recent findingsImportant, newly recognized mediators of cerebral arterial spasm after subarachnoid hemorrhage include superoxide free radicals, ferrous hemoglobin (which acts as a nitric oxide scavenger), endothelins, protein kinase C, and &rgr; kinase. Microvascular dysfunction and autoregulatory failure also has been an area of increasing research focus in recent years. New diagnostic modalities include measures of cerebral blood flow such as single-photon emission computed tomography and perfusion computed tomography, magnetic resonance imaging, intracranial brain oxygen tension probes, and jugular venous oxygen saturation monitors. Proton magnetic resonance spectroscopy and microdialysis can detect tissue biochemical abnormalities, but these techniques have not found their way into routine clinical practice as of yet. In addition to nimodipine and hypertensive hypervolemic therapy, promising new treatments for vasospasm or its ischemic complications include magnesium sulfate, fasudil hydrochloride, tirilazad mesylate, erythropoietin, and induced hypothermia. Balloon angioplasty has emerged as the primary weapon for treating medically refractory ischemia from vasospasm and in many centers is being used as a first-line treatment or even prophylactically.SummaryThe neurointensive care management of vasospasm after subarachnoid hemorrhage has evolved significantly over the past 10 years, with many new diagnostic modalities and promising treatments now available. Clinical trials are needed to evaluate the efficacy of these new techniques and to further define the optimal management of this often devastating complication.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewTo evaluate the rationale and the pharmacologic options for sedating neurointensive care patients.Recent findingsSedation is a fundamental element in the neurointensive care unit. Even if the sedative strategy in the neurointensive care unit shares the same general aims with intensive care, the characteristics of the patients in the neurointensive care unit pose other unique challenges and some specific indications. The primary aim of neurointensive care is to maintain adequate cerebral perfusion pressure, to control intracranial pressure, and to maintain an adequate mean arterial pressure. Reducing the brain's metabolic demand is an important treatment strategy, and analgesic and sedative agents are used to prevent undesirable increases in intracranial pressure. There are many different pharmacologic agents available, each with distinct advantages and disadvantages.SummaryThe pharmacokinetic and pharmacologic effects of the available sedatives used in neurointensive care patients are reviewed.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThe mesenteric hemodynamic response to circulatory shock is substantial and asymmetrical; the vasoconstrictive response disproportionately affects the mesenteric organs. The cardiac output is sustained partially, at no cost in nutrient flow to the mesenteric organs, by vasoconstriction of the mesenteric veins, resulting in the “autotransfusion” of up to 30% of the circulating blood volume into the systemic circulation.Recent findingsHemorrhagic or cardiogenic shock also results in decreased perfusion pressure, prompting selective vasoconstriction of the mesenteric arterioles to maintain perfusion pressure of the vital organs, here at the selective expense of the mesenteric organs. Septic shock may be associated with increased or decreased mesenteric blood flow but is characterized by increased oxygen consumption, exceeding the capability of mesenteric oxygen delivery.SummaryThe response to any of these conditions can, variably and unpredictably, cause hemorrhagic gastric stress erosions, nonocclusive mesenteric ischemia of the small bowel, ischemic colitis, ischemic hepatitis, acalculous cholecystitis, and/or ischemic pancreatitis. Injury to the mesenteric organs can also initiate the systemic inflammatory response syndrome and, consequently, multiple organ failure.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewAbdominal compartment syndrome (ACS) is the end result of sustained, uncorrected intraabdominal hypertension. In clinical and laboratory settings, ACS has been shown to adversely affect all vital organ systems. Although early descriptions emanated from the trauma literature, ACS is now encountered in all intensive care unit populations. In this review, we examine the literature and identify factors that may predict the onset of ACS.Recent findingsThe pathogenesis of ACS remains unclear, and few studies have sought to identify predictive clinical variables. Peak airway pressure and net 24-hour fluid gradient are the only variables that have been identified in the available literature as predictive of ACS development in controlled studies.SummaryThe earlier recognition of predictive variables and identification of patients at higher risk will hopefully lead to recognition and avoidance of the sequelae and increased mortality rate associated with ACS.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Purpose of reviewThis review focuses on the latest mechanistic understanding of the effects of estradiol on the splanchnic circulation and the possibility of estradiol treatment as an adjunct for the treatment of trauma–hemorrhage and sepsis.Recent findingsSystemic hypotension induced by shock accompanies marked alterations in blood flow to various organs. Decreased splanchnic perfusion is frequently observed after insults, such as severe hemorrhage or sepsis, which leads to the destruction of the intestinal mucosal barrier and hepatic dysfunction. Studies suggest that estradiol acts as a facilitator of the intestinal blood flow via the increased production of nitric oxide, decreased production of vasoconstrictors, attenuated neutrophil adhesion, and decreased formation of oxygen free radicals.SummaryTrauma–hemorrhage results in decreased circulating blood volume. In contrast, sepsis is an inflammatory state mainly mediated by bacterial products. However, these divergent insults show similar pathophysiologic alterations in terms of the splanchnic circulation. Because estradiol effectively protects the organs from circulatory failure after various adverse circulatory conditions, many studies are being performed to clarify the molecular mechanism of estradiol action with regard to tissue circulation. Estradiol improves the macro- and microcirculation of the splanchnic organs by multiple mechanisms. Nonetheless, it remains unclear which mechanism plays the most important role in the treatment of trauma–hemorrhage and sepsis. Additional studies are required to elucidate the precise mechanism of estradiol action and to determine the usefulness of estradiol treatment for severe hemorrhage and sepsis in patients.

ISSN:1070-5295    

出版商:OVID    

年代:2003

数据来源: OVID