PubMed Central (PMC3 - NLM DTD)
(2,081,148 recursos)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
Mostrando recursos 181 - 200 de 3,189
181.
Equipment review: Cooling catheters to induce therapeutic hypothermia? - Polderman, Kees H; Callaghan, Jeannie
There is growing acceptance within the medical community of induced (therapeutic) hypothermia as a tool to achieve neuroprotection and/or cardioprotection. Although much work remains to be done in identifying those clinical situations in which hypothermia can be effective, there is now sufficient evidence to regard it as a standard of care, at least for some indications such as selected patients with postanoxic encephalopathy. Thus, attention is now partly shifting from assessment of the clinical evidence of efficacy to technical and implementation issues. This review provides a list of criteria by which cooling devices can be judged, and specifically it discusses...
183.
Bench-to-bedside review: Thrombocytopenia-associated multiple organ failure a newly appreciated syndrome in the critically ill - Nguyen, Trung C; Carcillo, Joseph A
New onset thrombocytopenia and multiple organ failure (TAMOF) presages poor outcome in critical illness. Patients who resolve thrombocytopenia by day 14 are more likely to survive than those who do not. Patients with TAMOF have a spectrum of microangiopathic disorders that includes thrombotic thrombocytopenic purpura (TTP), disseminated intravascular coagulation (DIC) and secondary thrombotic microanigiopathy (TMA). Activated protein C is effective in resolving fibrin-mediated thrombosis (DIC); however, daily plasma exchange is the therapy of choice for removing ADAMTS 13 inhibitors and replenishing ADAMTS 13 activity which in turn resolves platelet: von Willebrand Factor mediated thrombosis (TTP/secondary TMA).
184.
Bench-to-bedside review: The role of glycosaminoglycans in respiratory disease - Souza-Fernandes, Alba B; Pelosi, Paolo; Rocco, Patricia RM
The extracellular matrix (ECM) plays a significant role in the mechanical behaviour of the lung parenchyma. The ECM is composed of a three-dimensional fibre mesh that is filled with various macromolecules, among which are the glycosaminoglycans (GAGs). GAGs are long, linear and highly charged heterogeneous polysaccharides that are composed of a variable number of repeating disaccharide units. There are two main types of GAGs: nonsulphated GAG (hyaluronic acid) and sulphated GAGs (heparan sulphate and heparin, chondroitin sulphate, dermatan sulphate, and keratan sulphate). With the exception of hyaluronic acid, GAGs are usually covalently attached to a protein core, forming an overall...
187.
Clinical review: Patient-ventilator interaction in chronic obstructive pulmonary disease - Jolliet, Philippe; Tassaux, Didier
Mechanically ventilated patients with chronic obstructive pulmonary disease often prove challenging to the clinician due to the complex pathophysiology of the disease and the high risk of patient-ventilator asynchrony. These problems are encountered in both intubated patients and those ventilated with noninvasive ventilation. Much knowledge has been gained over the years in our understanding of the mechanisms underlying the difficult interaction between these patients and the machines used to provide them with the ventilatory support they often require for prolonged periods. This paper attempts to summarize the various key issues of patient-ventilator interaction during pressure support ventilation, the most often...
189.
Live and let die: asymmetric dimethylarginine and septic shock - Böger, Rainer H
Nitric oxide (NO) is an important mediator of host defence and of vascular tone. In septic shock, upregulation of inducible NO synthase leads to the production of vast amounts of NO, which contribute to pathogen elimination but also to inappropriate vasodilation and to loss of vascular resistance. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of NO synthases shown to contribute to the regulation of vascular tone. ADMA was recently identified as a marker of organ dysfunction and mortality in intensive care patients and as a novel cardiovascular risk factor. In the present issue of Critical Care, a study by O'Dwyer...
190.
Bench-to-bedside review: Critical illness-associated cognitive dysfunction mechanisms, markers, and emerging therapeutics - Milbrandt, Eric B; Angus, Derek C
Cognitive dysfunction is common in critically ill patients, not only during the acute illness but also long after its resolution. A large number of pathophysiologic mechanisms are thought to underlie critical illness-associated cognitive dysfunction, including neuro-transmitter abnormalities and occult diffuse brain injury. Markers that could be used to evaluate the influence of specific mechanisms in individual patients include serum anticholinergic activity, certain brain proteins, and tissue sodium concentration determination via high-resolution three-dimensional magnetic resonance imaging. Although recent therapeutic advances in this area are exciting, they are still too immature to influence patient care. Additional research is needed if we are...
191.
Can you justify not using ultrasound guidance for central venous access? - Bodenham, Andrew R
Karakitsos and coworkers, in this journal, reported further compelling evidence on the value of ultrasound in guiding internal jugular vein catheterization. In a large, prospective, randomized study of 900 patients, comparisons were made between patients in whom the procedure was performed using landmark-based techniques and those assigned to ultrasound guidance. The key benefits from use of ultrasound included reduction in needle puncture time, increased overall success rate (100% versus 94%), reduction in carotid puncture (1% versus 11%), reduction in carotid haematoma (0.4% versus 8.4%), reduction in haemothorax (0% versus 1.7%), decreased pneumothorax (0% versus 2.4%) and reduction in catheter-related infection...
192.
Can passive leg raising be used to guide fluid administration? - De Backer, Daniel
Predicting fluid responsiveness has become a topic of major interest. Measurements of intravascular pressures and volumes often fail to predict the response to fluids, even though very low values are usually associated with a positive response to fluids. Dynamic indices reflecting respiratory-induced variations in stroke volume have been developed; however, these cannot be used in patients with arrhythmia or with spontaneous respiratory movements. The passive leg raising (PLR) test has been suggested to predict fluid responsiveness. PLR induces an abrupt increase in preload due to autotransfusion of blood contained in capacitance veins of the legs, which leads to an increase...
193.
Optimizing neurologic prognosis after cardiac arrest - Tirschwell, David
Neurologic disability is a feared outcome of resuscitation from cardiac arrest. The study by Rech and colleagues in the previous issue of Critical Care describes the use of neuron-specific enolase to inform an early prognosis in patients who survived in-hospital cardiac arrest. In their study 'none of the patients had a DNR order and there was no limitation of life support.' As a result, 10% of patients remained in a vegetative state at 6 months, a higher percentage than in other recent studies. The existence of a population of patients in which all are fully supported without withholding care or...
194.
Iatrogenesis, inflammation and organ injury: insights from a murine model - Marshall, John C
The complex biology of critical illness not only reflects the initial insult that brought the patient to the intensive care unit but also, and perhaps even more importantly, it reflects the consequences of the many clinical interventions initiated to support life during a time of lethal organ system insufficiency. The latter may amplify or modify the response to the former and are eminently amenable to modulation by changes in practice. However, they rarely figure in conceptual models of critical illness and are almost never accounted for in preclinical models of disease. In the preceding issue of Critical Care, O'Mahony and...
196.
Vasopressin in vasodilatory shock: ensure organ blood flow, but take care of the heart! - Dünser, Martin W; Hasibeder, Walter R
Supplementary arginine vasopressin infusion in advanced vasodilatory shock may be accompanied by a decrease in cardiac index and systemic oxygen transport capacity in approximately 40% of patients. While a reduction of cardiac output most frequently occurs in patients with hyperdynamic circulation, it is less often observed in patients with low cardiac index. Infusion of inotropes, such as dobutamine, may be an effective strategy to restore systemic blood flow. However, when administering inotropic drugs, systemic blood flow should be increased to adequately meet systemic demands (assessed by central or mixed venous oxygen saturation) without putting an excessive beta-adrenergic stress on the...
197.
Heterotopic ossification a long-term consequence of prolonged immobility - Hudson, Sonia J; Brett, Stephen J
Heterotopic ossification is a condition affecting an appreciable minority of critical care patients; it can have long-lasting effects on recovery and return to functional status. Ectopic bone forms in soft tissues near the large joints, causing pain, swelling, limitation of movement and ultimate disability. X-ray changes may be delayed for several weeks after the diagnosis is clinically suspected. Magnetic resonance imaging may be more sensitive for detecting early changes, yielding positive results several weeks before X-rays. However it is not clear that diagnosing the process early will influence long-term patient outcome, because no effective treatments are available.
198.
Ethics review: Position papers and policies are they really helpful to front-line ICU teams? - Hawryluck, Laura
During the past few years the ethics sections of critical care societies have proposed a number of policies describing the goals of intensive care unit (ICU) care and providing broad guidance on the diagnoses and physiological criteria that would mandate using the specialized skill and technologies of an ICU environment. Discussions on what constitutes appropriate use of such scarce resources, incorporating cultural and religious beliefs and exploring how they interact with these medical criteria, remain vague. To date, these policies do not provide any definitive guidance in the difficult decision making faced by clinicians. Some argue that they were never...
199.
Bench-to-bedside review: High-frequency oscillatory ventilation in adults with acute respiratory distress syndrome - Downar, James; Mehta, Sangeeta
Mechanical ventilation is the cornerstone of therapy for patients with acute respiratory distress syndrome (ARDS). Paradoxically, mechanical ventilation can exacerbate lung damage a phenomenon known as ventilator-induced lung injury. While new ventilation strategies have reduced the mortality rate in patients with ARDS, this mortality rate still remains high. High-frequency oscillatory ventilation (HFOV) is an unconventional form of ventilation that may improve oxygenation in patients with ARDS, while limiting further lung injury associated with high ventilatory pressures and volumes delivered during conventional ventilation. HFOV has been used for almost two decades in the neonatal population, but there is more limited...
200.
Bench-to-bedside review: The role of activated protein C in maintaining endothelial tight junction function and its relationship to organ injury - Looney, Mark R; Matthay, Michael A
Activated protein C (APC) has emerged as a novel therapeutic agent for use in selected patients with severe sepsis, even though the mechanism of its benefit is not well established. APC has anticoagulant, anti-inflammatory, antiapoptotic, and profibrinolytic properties, but it is not clear through which of these mechanisms APC exerts its benefit in severe sepsis. Focus has recently turned to the role of APC in maintaining endothelial barrier function, and in vitro and in vivo studies have examined this relationship. This article critically reviews these studies, with a focus on potential mechanisms of action.
181.
