27 research outputs found
Are antifibrinolytic drugs equivalent in reducing blood loss and transfusion in cardiac surgery? A meta-analysis of randomized head-to-head trials
BACKGROUND: Aprotinin has been shown to be effective in reducing peri-operative blood loss and the need for re-operation due to continued bleeding in cardiac surgery. The lysine analogues tranexamic acid (TXA) and epsilon aminocaproic acid (EACA) are cheaper, but it is not known if they are as effective as aprotinin. METHODS: Studies were identified by searching electronic databases and bibliographies of published articles. Data from head-to-head trials were pooled using a conventional (Cochrane) meta-analytic approach and a Bayesian approach which estimated the posterior probability of TXA and EACA being equivalent to aprotinin; we used as a non-inferiority boundary a 20% increase in the rates of transfusion or re-operation because of bleeding. RESULTS: Peri-operative blood loss was significantly greater with TXA and EACA than with aprotinin: weighted mean differences were 106 mls (95% CI 37 to 227 mls) and 185 mls (95% CI 134 to 235 mls) respectively. The pooled relative risks (RR) of receiving an allogeneic red blood cell (RBC) transfusion with TXA and EACA, compared with aprotinin, were 1.08 (95% CI 0.88 to 1.32) and 1.14 (95% CI 0.84 to 1.55) respectively. The equivalent Bayesian posterior mean relative risks were 1.15 (95% Bayesian Credible Interval [BCI] 0.90 to 1.68) and 1.21 (95% BCI 0.79 to 1.82) respectively. For transfusion, using a 20% non-inferiority boundary, the posterior probabilities of TXA and EACA being non-inferior to aprotinin were 0.82 and 0.76 respectively. For re-operation the Cochrane RR for TXA vs. aprotinin was 0.98 (95% CI 0.51 to 1.88), compared with a posterior mean Bayesian RR of 0.63 (95% BCI 0.16 to 1.46). The posterior probability of TXA being non-inferior to aprotinin was 0.92, but this was sensitive to the inclusion of one small trial. CONCLUSION: The available data are conflicting regarding the equivalence of lysine analogues and aprotinin in reducing peri-operative bleeding, transfusion and the need for re-operation. Decisions are sensitive to the choice of clinical outcome and non-inferiority boundary. The data are an uncertain basis for replacing aprotinin with the cheaper lysine analogues in clinical practice. Progress has been hampered by small trials and failure to study clinically relevant outcomes
Evaluation of the HadGEM3-A simulations in view of detection and attribution of human influence on extreme events in Europe
A detailed analysis is carried out to assess the HadGEM3-A global atmospheric model skill in simulating extreme temperatures, precipitation and storm surges in Europe in the view of their attribution to human influence. The analysis is performed based on an ensemble of 15 atmospheric simulations forced with observed Sea Surface Temperature of the 54 year period 1960-2013. These simulations, together with dual simulations without human influence in the forcing, are intended to be used in weather and climate event attribution. The analysis investigates the main processes leading to extreme events, including atmospheric circulation patterns, their links with temperature extremes, land-atmosphere and troposphere-stratosphere interactions. It also compares observed and simulated variability, trends and generalized extreme value theory parameters for temperature and precipitation. One of the most striking findings is the ability of the model to capture North Atlantic atmospheric weather regimes as obtained from a cluster analysis of sea level pressure fields. The model also reproduces the main observed weather patterns responsible for temperature and precipitation extreme events. However, biases are found in many physical processes. Slightly excessive drying may be the cause of an overestimated summer interannual variability and too intense heat waves, especially in central/northern Europe. However, this does not seem to hinder proper simulation of summer temperature trends. Cold extremes appear well simulated, as well as the underlying blocking frequency and stratosphere-troposphere interactions. Extreme precipitation amounts are overestimated and too variable. The atmospheric conditions leading to storm surges were also examined in the Baltics region. There, simulated weather conditions appear not to be leading to strong enough storm surges, but winds were found in very good agreement with reanalyses. The performance in reproducing atmospheric weather patterns indicates that biases mainly originate from local and regional physical processes. This makes local bias adjustment meaningful for climate change attribution
Dynamics of Socioeconomic Exposure, Vulnerability and Impacts of Recent Droughts in Argentina
During the last 20 years, Argentina experienced several extreme and widespread droughts in many different regions, including the core cropland areas. The most devastating recent events were recorded in the years 2006, 2009 and 2011. Reported impacts of the main events induced losses of more than 4 billion U.S. dollars and more than 1 million persons were reported to be directly or indirectly affected. In this paper, we analyse the drought risk in Argentina, taking into account recent information on drought hazard, exposure and vulnerability. Accordingly, we identified the most severe droughts in Argentina during the 2000–2015 period using a combination of drought hazard indicators and exposure layers. Three main events were identified: (1) during spring 2006 droughts peaked in the northeast of Argentina, (2) in 2009 precipitation deficits indicated a drought epicenter in the central Argentinian plains, and (3) in 2011 the northern Patagonia region experienced a combination of natural disasters due to severe drought conditions and a devastating volcanic eruption. Furthermore, we analysed the dynamics of drought exposure for the population and the main economic sectors affected by municipality, i.e., agriculture and livestock production. Assets exposed to droughts have been identified with several records of drought impacts and declarations of farming emergencies. We show that by combining exposure and vulnerability with drought intensity it is feasible to detect the likelihood of regional impacts in different sectors
Estimating drought risk across Europe from reported drought impacts, drought indices, and vulnerability factors
Drought is one of the most costly natural hazards in Europe. Due to its
complexity, drought risk, meant as the combination of the natural hazard and
societal vulnerability, is difficult to define and challenging to detect and
predict, as the impacts of drought are very diverse, covering the breadth of
socioeconomic and environmental systems. Pan-European maps of drought risk
could inform the elaboration of guidelines and policies to address its
documented severity and impact across borders. This work tests the
capability of commonly applied drought indices and vulnerability factors to
predict annual drought impact occurrence for different sectors and macro
regions in Europe and combines information on past drought impacts, drought
indices, and vulnerability factors into estimates of drought risk at the
pan-European scale. This hybrid approach bridges the gap between
traditional vulnerability assessment and probabilistic impact prediction in
a statistical modelling framework. Multivariable logistic regression was
applied to predict the likelihood of impact occurrence on an annual basis
for particular impact categories and European macro regions. The results
indicate sector- and macro-region-specific sensitivities of drought indices,
with the Standardized Precipitation Evapotranspiration Index (SPEI) for a
12-month accumulation period as the overall best hazard predictor.
Vulnerability factors have only limited ability to predict drought impacts
as single predictors, with information about land use and water resources
being the best vulnerability-based predictors. The application of the
hybrid approach revealed strong regional and sector-specific differences
in drought risk across Europe. The majority of the best predictor combinations
rely on a combination of SPEI for shorter and longer accumulation periods,
and a combination of information on land use and water resources. The added
value of integrating regional vulnerability information with drought risk
prediction could be proven. Thus, the study contributes to the overall
understanding of drivers of drought impacts, appropriateness of drought
indices selection for specific applications, and drought risk assessment
Impacts of natural hazards in Europe
Climate change has caused noticeable effects on human health in Europe, mainly as a result of extreme events, an increase in climate-sensitive diseases, and a deterioration in environmental and social conditions. Heat waves were thedeadliest extreme weather event in the period 1991–2015 in Europe.Increase in the frequency and intensity of extreme weather- and climate-related events may lead to more disastrous impacts on ecosystems and their services. Management of ecosystems can help to avoid or significantly reduce these impacts.The total reported economic losses caused by extreme weather- and climate-related events in the EEA member countries over the period 1980-2015 amount to around EUR 433 billion (in 2015 values). A large share of the total losses (70 %) has been caused by a small number of events (3 %)
Effects of Aprotinin During Cardiopulmonary Bypass in Patients Treated with Acetylsalicylic Acid
Tackling Growing Drought Risks—The Need for a Systemic Perspective
Abstract In the last few years, the world has experienced numerous extreme droughts with adverse direct, cascading, and systemic impacts. Despite more frequent and severe events, drought risk assessment is still incipient compared to that of other meteorological and climate hazards. This is mainly due to the complexity of drought, the high level of uncertainties in its analysis, and the lack of community agreement on a common framework to tackle the problem. Here, we outline that to effectively assess and manage drought risks, a systemic perspective is needed. We propose a novel drought risk framework that highlights the systemic nature of drought risks, and show its operationalization using the example of the 2022 drought in Europe. This research emphasizes that solutions to tackle growing drought risks should not only consider the underlying drivers of drought risks for different sectors, systems or regions, but also be based on an understanding of sector/system interdependencies, feedbacks, dynamics, compounding and concurring hazards, as well as possible tipping points and globally and/or regionally networked risks