Critical care medicine
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To provide a contemporary review of the diagnosis and management of necrotizing soft-tissue infections. ⋯ The mortality for necrotizing soft-tissue infections appears to be decreasing, possibly due to improved recognition and earlier delivery of more effective therapy. Establishing a diagnosis and initiating treatment as soon as possible provides the best opportunity for a good outcome.
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Critical care medicine · Sep 2011
The Impella 2.5 and 5.0 devices for ST-elevation myocardial infarction patients presenting with severe and profound cardiogenic shock: the Academic Medical Center intensive care unit experience.
Cardiogenic shock remains an important therapeutic challenge, with high in-hospital mortality rates. Mechanical circulatory support may be beneficial in these patients. Since the efficacy of the intra-aortic balloon pump seems limited, new percutaneously placed mechanical left ventricular support devices, such as the Impella system, have been developed for this purpose. Our current purpose was to describe our experience with the Impella system in patients with ST-elevation myocardial infarction presenting in profound cardiogenic shock, who were admitted to our intensive care unit for mechanical ventilation. ⋯ In ST-elevation myocardial infarction patients with severe and profound cardiogenic shock, our initial experience suggests improved survival in patients who received immediate Impella 5.0 treatment, as well as in patients who were upgraded from 2.5 to 5.0 support, when compared to patients who received only Impella 2.5 support.
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Critical care medicine · Sep 2011
Relative contribution of three main virulence factors in Pseudomonas aeruginosa pneumonia.
The pathogenesis and the outcome of Pseudomonas aeruginosa ventilator-acquired pneumonia depend on the virulence factors displayed by the bacteria as well as the host response. Thus, quorum sensing, lipopolysaccharide, and type 3 secretion system have each individually been shown to be important virulence systems in laboratory reference strains. However, the relative contribution of these three factors to the in vivo pathogenicity of clinically relevant strains has never been studied. We analyzed the virulence of 56 nonclonal Pseudomonas aeruginosa strains isolated from critically ill patients with ventilator-acquired pneumonia. To avoid the variation of human immune response, we used a murine model of pneumonia. The aim was to determine which virulence factor was the most important. ⋯ In a murine model of pneumonia, our data suggest that type 3 secretion system and elastase are the most important virulence factors in clinically relevant P. aeruginosa strains.
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Critical care medicine · Sep 2011
The value of positive end-expiratory pressure and Fio₂ criteria in the definition of the acute respiratory distress syndrome.
The criteria that define acute lung injury and the acute respiratory distress syndrome include PaO₂/Fio₂ but not positive end-expiratory pressure or Fio2. PaO2/Fio2 ratios of some patients increase substantially after mechanical ventilation with positive end-expiratory pressure of 5-10 cm H₂O, and the mortality of these patients may be lower than those whose PaO₂/Fio₂ratios remain <200. Also, PaO₂/Fio₂ may increase when Fio2 is raised from moderate to high levels, suggesting that patients with similar PaO₂/Fio₂ ratios but different Fio₂ levels have different risks of mortality. The primary purpose of this study was to assess the value of adding baseline positive end-expiratory pressure and Fio₂ to PaO₂/Fio₂ for predicting mortality of acute lung injury/acute respiratory distress syndrome patients enrolled in Acute Respiratory Distress Syndrome Network clinical trials. We also assessed effects of two study interventions on clinical outcomes in subsets of patients with mild and severe hypoxemia as defined by PaO₂/Fio₂. ⋯ At Acute Respiratory Distress Syndrome Network hospitals, the addition of baseline positive end-expiratory pressure would not have increased the value of PaO₂/Fio₂ for predicting mortality of acute lung injury/acute respiratory distress syndrome patients. In contrast, the addition of baseline Fio2 to PaO₂/Fio₂ could be used to identify subsets of patients with low or high mortality.
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Critical care medicine · Sep 2011
CommentGuidelines for the determination of brain death in infants and children: an update of the 1987 Task Force recommendations.
To review and revise the 1987 pediatric brain death guidelines. ⋯ 1) Determination of brain death in term newborns, infants, and children is a clinical diagnosis based on the absence of neurologic function with a known irreversible cause of coma. Because of insufficient data in the literature, recommendations for preterm infants <37 wks gestational age are not included in this guideline. 2) Hypotension, hypothermia, and metabolic disturbances should be treated and corrected and medications that can interfere with the neurologic examination and apnea testing should be discontinued allowing for adequate clearance before proceeding with these evaluations. 3) Two examinations, including apnea testing with each examination separated by an observation period, are required. Examinations should be performed by different attending physicians. Apnea testing may be performed by the same physician. An observation period of 24 hrs for term newborns (37 wks gestational age) to 30 days of age and 12 hrs for infants and children (>30 days to 18 yrs) is recommended. The first examination determines the child has met the accepted neurologic examination criteria for brain death. The second examination confirms brain death based on an unchanged and irreversible condition. Assessment of neurologic function after cardiopulmonary resuscitation or other severe acute brain injuries should be deferred for ≥24 hrs if there are concerns or inconsistencies in the examination. 4) Apnea testing to support the diagnosis of brain death must be performed safely and requires documentation of an arterial Paco2 20 mm Hg above the baseline and ≥60 mm Hg with no respiratory effort during the testing period. If the apnea test cannot be safely completed, an ancillary study should be performed. 5) Ancillary studies (electroencephalogram and radionuclide cerebral blood flow) are not required to establish brain death and are not a substitute for the neurologic examination. Ancillary studies may be used to assist the clinician in making the diagnosis of brain death a) when components of the examination or apnea testing cannot be completed safely as a result of the underlying medical condition of the patient; b) if there is uncertainty about the results of the neurologic examination; c) if a medication effect may be present; or d) to reduce the interexamination observation period. When ancillary studies are used, a second clinical examination and apnea test should be performed and components that can be completed must remain consistent with brain death. In this instance, the observation interval may be shortened and the second neurologic examination and apnea test (or all components that are able to be completed safely) can be performed at any time thereafter. 6) Death is declared when these criteria are fulfilled.