113,906 research outputs found
Mechanisms and clinical consequences of acute lung injury.
No full text.Acute respiratory distress syndrome (ARDS) was first described in 1967, and since then there have been a large number of studies addressing its pathogenesis and therapies. Despite intense research efforts, very few therapies for ARDS have been shown to be effective other than the use of lung protection strategies. The scarcity of therapeutic choices is related to the intricate pathogenesis of the syndrome and to insensitive and aspecific criteria to diagnose this profound acute respiratory failure. The aim of this paper is to summarize advances of new ARDS definitions and provide an overview of new relevant signaling pathways that mediate acute lung injury
La trincea e i pascoli. Il socialismo di Emilio Lussu. Un documento inedito dalla nastroteca dell’Istituto Ernesto de Martino
No full textLong memory and crude oil’s price predictability
No full textThis paper discusses the usefulness of the long term memory property in price prediction. In particular, the Hurst’s exponents related to a wide set of portfolios generated by three crude oils are estimated by using the detrended fluctuation analysis. To this aim, the daily empirical data on West Texas Intermediate, Brent crude oil and Dubai crude oil for a period of more than 10 years have been considered. It is shown that specific combinations are associated to persistence/antipersistence long-run behaviors, and this highlights the presence of statistical arbitrage opportunities. Such an outcome shows that long term memory can effectively serve as price predictor
Anesthetic optimization for nonheartbeating donors
No full textPURPOSE OF REVIEW:
One of the newest strategies to enlarge the pool of organ donors is to consider the category of donors after cardiac death rather than only after brain death. Prompt and accurate identification of potential donors and appropriate care is necessary to optimize the management of nonheartbeating donors.
RECENT FINDINGS:
Organ procurement derived from donors after cardiac death is becoming a part of the policy of major transplantation hospitals, forcing them to consider the practical interventions and ethical implications regarding this practice. Typical donors are patients affected by irreversible brain injuries, high spinal cord injury and end-stage musculoskeletal diseases. To start the process the following three conditions must be met. Withdrawal of life-sustaining therapies must be considered independently from transplantation. Withdrawal of life support requires a careful titration of the drugs controlling pain, anxiety and discomfort. Organ harvesting has to be initiated after at least 2-5 min of confirmed cardiac death.
SUMMARY:
In order to increase the number of organs available for transplantation, donation from nonheartbeating donors has been recently proposed. Identification of the key aspects of the donation after cardiac death should be fully achieved by the team involved in the transplantation program. Development of hospital policies and identification of receivers who are most likely to benefit from this strategy require further studies to assess long-term outcome and to identify ethical aspects concerning different religious and cultural backgrounds
Long memory and crude oil’s price predictability
No full textThis paper discusses the usefulness of the long term memory property in price prediction. In particular, the Hurst’s exponents related to a wide set of portfolios generated by three crude oils are estimated by using the detrended fluctuation analysis. To this aim, the daily empirical data on West Texas Intermediate, Brent crude oil and Dubai crude oil for a period of more than 10 years have been considered. It is shown that specific combinations are associated to persistence/antipersistence long-run behaviors, and this highlights the presence of statistical arbitrage opportunities. Such an outcome shows that long term memory can effectively serve as price predictor
Acute respiratory distress syndrome: update on the latest developments in basic and clinical research
No full textPURPOSE OF REVIEW: Acute lung injury/acute respiratory distress syndrome is a common, serious condition affecting a heterogeneous population of critically ill patients. Other than low tidal volume ventilation, no specific therapy has improved survival. Understanding the epidemiology, pathogenesis, and lessons to be learned from previous clinical trials is necessary for the development of new therapies and the rational design of studies assessing their efficacy. RECENT FINDINGS: Acute lung injury/acute respiratory distress syndrome occurs in 6-8% of the general intensive care unit population, with a mortality of 32-45%. A recent epidemiologic study found that multi-organ dysfunction, use of tidal volumes higher than 6 ml/kg, and high mean fluid balance were independent risks for mortality. Although high levels of inflammatory mediators are also markers for acute respiratory distress syndrome development and death, short courses of high-dose steroids are not effective in acute cases. The latest theory of biotrauma proposes cellular mechanisms by which mechanical ventilation incites a local and systemic inflammatory response; protective lung ventilation with low tidal volumes can attenuate this inflammation and injury to distal organs. Endogenous surfactant function is clearly impaired, but no commercially available surfactant preparation has been shown to reduce mortality. Results of trials to determine efficacy of steroids in late cases and optimal fluid management are pending. SUMMARY: The results of recent clinical trials have raised more questions. Further study of the inflammatory response, surfactant regulation, and the cellular impact of mechanical ventilation should help to develop new therapies, target patients most likely to benefit, and identify appropriate timing of intervention
When pressure does not mean volume? Body mass index may account for the dissociation
No full textLow tidal volume (VT 6 ml/predicted body weight)
pressure limited (plateau pressure <30 cmH2O)
protective ventilation as proposed by the ARDS
Network was associated with an improvement in
mortality and is considered the gold standard for
acute respiratory distress syndrome (ARDS) ventilation
strategies. Limiting plateau pressure minimizes
ventilator-induced lung injury by reducing the
trans-pulmonary pressure, which is the real alveolar
distending pressure. However, in the presence of
chest wall elastance impairment, as observed in
obese patients, plateau pressure underestimates the
trans-pulmonary pressure and derecrutiment at low
distending pressure could occur. Moreover, low tidal
volume to keep plateau pressure <30 cmH2O could
be associated with large diff erences compared to
measured total lung capacity. Quantitative bedside
techniques that are able to measure lung volumes
together with trans-pulmonary pressure could expand
our chances to tailor mechanical ventilation in ARD
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