106 research outputs found

    Spontaneous Breathing in Early Acute Respiratory Distress Syndrome: Insights From the Large Observational Study to UNderstand the Global Impact of Severe Acute Respiratory FailurE Study

    Get PDF
    OBJECTIVES: To describe the characteristics and outcomes of patients with acute respiratory distress syndrome with or without spontaneous breathing and to investigate whether the effects of spontaneous breathing on outcome depend on acute respiratory distress syndrome severity. DESIGN: Planned secondary analysis of a prospective, observational, multicentre cohort study. SETTING: International sample of 459 ICUs from 50 countries. PATIENTS: Patients with acute respiratory distress syndrome and at least 2 days of invasive mechanical ventilation and available data for the mode of mechanical ventilation and respiratory rate for the 2 first days. INTERVENTIONS: Analysis of patients with and without spontaneous breathing, defined by the mode of mechanical ventilation and by actual respiratory rate compared with set respiratory rate during the first 48 hours of mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Spontaneous breathing was present in 67% of patients with mild acute respiratory distress syndrome, 58% of patients with moderate acute respiratory distress syndrome, and 46% of patients with severe acute respiratory distress syndrome. Patients with spontaneous breathing were older and had lower acute respiratory distress syndrome severity, Sequential Organ Failure Assessment scores, ICU and hospital mortality, and were less likely to be diagnosed with acute respiratory distress syndrome by clinicians. In adjusted analysis, spontaneous breathing during the first 2 days was not associated with an effect on ICU or hospital mortality (33% vs 37%; odds ratio, 1.18 [0.92-1.51]; p = 0.19 and 37% vs 41%; odds ratio, 1.18 [0.93-1.50]; p = 0.196, respectively ). Spontaneous breathing was associated with increased ventilator-free days (13 [0-22] vs 8 [0-20]; p = 0.014) and shorter duration of ICU stay (11 [6-20] vs 12 [7-22]; p = 0.04). CONCLUSIONS: Spontaneous breathing is common in patients with acute respiratory distress syndrome during the first 48 hours of mechanical ventilation. Spontaneous breathing is not associated with worse outcomes and may hasten liberation from the ventilator and from ICU. Although these results support the use of spontaneous breathing in patients with acute respiratory distress syndrome independent of acute respiratory distress syndrome severity, the use of controlled ventilation indicates a bias toward use in patients with higher disease severity. In addition, because the lack of reliable data on inspiratory effort in our study, prospective studies incorporating the magnitude of inspiratory effort and adjusting for all potential severity confounders are required

    Identifying associations between diabetes and acute respiratory distress syndrome in patients with acute hypoxemic respiratory failure: an analysis of the LUNG SAFE database

    Get PDF
    Background: Diabetes mellitus is a common co-existing disease in the critically ill. Diabetes mellitus may reduce the risk of acute respiratory distress syndrome (ARDS), but data from previous studies are conflicting. The objective of this study was to evaluate associations between pre-existing diabetes mellitus and ARDS in critically ill patients with acute hypoxemic respiratory failure (AHRF). Methods: An ancillary analysis of a global, multi-centre prospective observational study (LUNG SAFE) was undertaken. LUNG SAFE evaluated all patients admitted to an intensive care unit (ICU) over a 4-week period, that required mechanical ventilation and met AHRF criteria. Patients who had their AHRF fully explained by cardiac failure were excluded. Important clinical characteristics were included in a stepwise selection approach (forward and backward selection combined with a significance level of 0.05) to identify a set of independent variables associated with having ARDS at any time, developing ARDS (defined as ARDS occurring after day 2 from meeting AHRF criteria) and with hospital mortality. Furthermore, propensity score analysis was undertaken to account for the differences in baseline characteristics between patients with and without diabetes mellitus, and the association between diabetes mellitus and outcomes of interest was assessed on matched samples. Results: Of the 4107 patients with AHRF included in this study, 3022 (73.6%) patients fulfilled ARDS criteria at admission or developed ARDS during their ICU stay. Diabetes mellitus was a pre-existing co-morbidity in 913 patients (22.2% of patients with AHRF). In multivariable analysis, there was no association between diabetes mellitus and having ARDS (OR 0.93 (0.78-1.11); p = 0.39), developing ARDS late (OR 0.79 (0.54-1.15); p = 0.22), or hospital mortality in patients with ARDS (1.15 (0.93-1.42); p = 0.19). In a matched sample of patients, there was no association between diabetes mellitus and outcomes of interest. Conclusions: In a large, global observational study of patients with AHRF, no association was found between diabetes mellitus and having ARDS, developing ARDS, or outcomes from ARDS. Trial registration: NCT02010073. Registered on 12 December 2013

    Epidemiology and patterns of tracheostomy practice in patients with acute respiratory distress syndrome in ICUs across 50 countries

    Get PDF
    Background: To better understand the epidemiology and patterns of tracheostomy practice for patients with acute respiratory distress syndrome (ARDS), we investigated the current usage of tracheostomy in patients with ARDS recruited into the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG-SAFE) study. Methods: This is a secondary analysis of LUNG-SAFE, an international, multicenter, prospective cohort study of patients receiving invasive or noninvasive ventilation in 50 countries spanning 5 continents. The study was carried out over 4 weeks consecutively in the winter of 2014, and 459 ICUs participated. We evaluated the clinical characteristics, management and outcomes of patients that received tracheostomy, in the cohort of patients that developed ARDS on day 1-2 of acute hypoxemic respiratory failure, and in a subsequent propensity-matched cohort. Results: Of the 2377 patients with ARDS that fulfilled the inclusion criteria, 309 (13.0%) underwent tracheostomy during their ICU stay. Patients from high-income European countries (n = 198/1263) more frequently underwent tracheostomy compared to patients from non-European high-income countries (n = 63/649) or patients from middle-income countries (n = 48/465). Only 86/309 (27.8%) underwent tracheostomy on or before day 7, while the median timing of tracheostomy was 14 (Q1-Q3, 7-21) days after onset of ARDS. In the subsample matched by propensity score, ICU and hospital stay were longer in patients with tracheostomy. While patients with tracheostomy had the highest survival probability, there was no difference in 60-day or 90-day mortality in either the patient subgroup that survived for at least 5 days in ICU, or in the propensity-matched subsample. Conclusions: Most patients that receive tracheostomy do so after the first week of critical illness. Tracheostomy may prolong patient survival but does not reduce 60-day or 90-day mortality. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013

    First measurement of the |t|-dependence of coherent J/ψ photonuclear production

    Get PDF
    The first measurement of the cross section for coherent J/ψ photoproduction as a function of |t|, the square of the momentum transferred between the incoming and outgoing target nucleus, is presented. The data were measured with the ALICE detector in ultra-peripheral Pb–Pb collisions at a centre-of-mass energy per nucleon pair sNN=5.02TeV with the J/ψ produced in the central rapidity region |y|<0.8, which corresponds to the small Bjorken-x range (0.3−1.4)×10−3. The measured |t|-dependence is not described by computations based only on the Pb nuclear form factor, while the photonuclear cross section is better reproduced by models including shadowing according to the leading-twist approximation, or gluon-saturation effects from the impact-parameter dependent Balitsky–Kovchegov equation. These new results are therefore a valid tool to constrain the relevant model parameters and to investigate the transverse gluonic structure at very low Bjorken-x.publishedVersio

    Resolving the strange behavior of extraterrestrial potassium in the upper atmosphere

    Get PDF
    It has been known since the 1960s that the layers of Na and K atoms, which occur between 80 and 105 km in the Earth's atmosphere as a result of meteoric ablation, exhibit completely different seasonal behavior. In the extratropics Na varies annually, with a pronounced wintertime maximum and summertime minimum. However, K varies semiannually with a small summertime maximum and minima at the equinoxes. This contrasting behavior has never been satisfactorily explained. Here we use a combination of electronic structure and chemical kinetic rate theory to determine two key differences in the chemistries of K and Na. First, the neutralization of K+ ions is only favored at low temperatures during summer. Second, cycling between K and its major neutral reservoir KHCO3 is essentially temperature independent. A whole atmosphere model incorporating this new chemistry, together with a meteor input function, now correctly predicts the seasonal behavior of the K layer

    ALICE Collaboration

    Get PDF

    Recurrence After Liver Resection of Colorectal Liver Metastases: Repeat Resection or Ablation Followed by Hepatic Arterial Infusion Pump Chemotherapy

    Get PDF
    Background: The aim of this study was to investigate the effectiveness of adjuvant hepatic arterial infusion pump (HAIP) chemotherapy after complete resection or ablation of recurrent colorectal liver metastases (CRLM). Methods: A retrospective cohort study was conducted of patients from two centers who were treated with resection and/or ablation of recurrent CRLM only between 1992 and 2018. Overall survival (OS) and hepatic disease-free survival (hDFS) were estimated using the Kaplan–Meier method. The Cox regression method was used to calculate hazard ratios (HRs) with corresponding 95% confidence intervals (CI). Results: Of 374 eligible patients, 81 (22%) were treated with adjuvant HAIP chemotherapy. The median follow-up for survivors was 65 months (IQR 32–118 months). Patients receiving adjuvant HAIP were more likely to have multifocal disease and receive perioperative systemic chemotherapy at time of resection for recurrence. A median hDFS of 46 months (95% CI 29–81 months) was found in patients treated with adjuvant HAIP compared with 18 months (95% CI 15–26 months) in patients treated with resection and/or ablation alone (p = 0.001). The median OS and 5-year OS were 89 months (95% CI 52–126 months) and 66%, respectively, in patients treated with adjuvant HAIP compared with 57 months (95% CI 47–67 months) and 47%, respectively, in patients treated with resection and/or ablation only (p = 0.002). Adjuvant HAIP was associated with superior hDFS (adjusted HR 0.599, 95% CI 0.38–0.93, p = 0.02) and OS (adjusted HR 0.59, 95% CI 0.38–0.92, p = 0.02) in multivariable analysis. Conclusion: Adjuvant HAIP chemotherapy after resection and/or ablation of recurrent CRLM is associated with superior hDFS and OS

    Adjuvant Hepatic Arterial Infusion Pump Chemotherapy After Resection of Colorectal Liver Metastases: Results of a Safety and Feasibility Study in The Netherlands

    Get PDF
    Background. The 10-year overall survival with adjuvant hepatic arterial infusion pump (HAIP) chemotherapy after resection of colorectal liver metastases (CRLMs) was 61% in clinical trials from Memorial Sloan Kettering Cancer Center. A pilot study was performed to evaluate the safety and feasibility of adjuvant HAIP chemotherapy in patients with resectable CRLMs. Study Design. A phase II study was performed in two centers in The Netherlands. Patients with resectable CRLM without extrahepatic disease were eligible. All patients underwent complete resection and/or ablation of CRLMs and pump implantation. Safety was determined by the 90-day HAIP-related postoperative complications from the day of pump placement (Clavien-Dindo classification, grade III or higher) and feasibility by the successful administration of the first cycle of HAIP chemotherapy. Results. A total of 20 patients, with a median age of 57 years (interquartile range [IQR] 51-64) were included. Grade III or higher HAIP-related postoperative complications were found in two patients (10%), both of whom had a reoperation (without laparotomy) to replace a pump with a slow flow rate or to reposition a flipped pump. No arterial bleeding, arterial dissection, arterial thrombosis, extrahepatic perfusion, pump pocket hematoma, or pump pocket infections were found within 90 days after surgery. After a median of 43 days (IQR 29-52) following surgery, all patients received the first dose of HAIP chemotherapy, which was completed uneventfully in all patients. Conclusion. Pump implantation is safe, and administration of HAIP chemotherapy is feasible, in patients with resectable CRLMs, after training of a dedicated multidisciplinary team

    Effect of cadmium on the floor of the mouth on rats during lactation Efeito do cádmio no soalho da boca de ratos durante a lactação

    No full text
    Cadmium (Cd) present in the air, drinking water and food has the potential to affect the health of people, mainly those who live in highly industrialized regions. Cd affects placental function, may cross the placental barrier and directly modify fetal development. It is also excreted into milk. The body is particularly susceptible to Cd exposure during perinatal period. The effect on rat oral epithelium (floor of the mouth) after continuous exposure to drinking water containing low levels of Cd during lactation was studied. Female rats were supplied with ad libitum drinking water containing 300 mg/l of CdCl2 throughout the whole lactation period. Control animals received a similar volume of water without Cd. Lactating rats (21 day-old) were killed by lethal dose of anesthetic. The heads were retrieved, fixed in "alfac" solution (alcohol, acetic acid and formaldehyde) for 24 h, serially sectioned in frontal plane, at the level of the first molars. The 6 µm sections were then stained with hematoxylin and eosin. Nuclear epithelium parameters were estimated, as well as cytoplasm and cell volume, nucleus/cytoplasm ratio, numeric and surface densities, and epithelial thickness. Mean body weight was 34.86 g for the control group and 18.56 g for the Cd-treated group. Histologically, the floor of the mouth epithelium was thinner in the treated group, with smaller and more numerous cells. In this experiment, Cd induced epithelial hypotrophy, indicating a direct action in oral mucosa cells, besides retarded development of the pups.<br>O cádmio (Cd) do ar, da água e dos alimentos tem o potencial de afetar a saúde das pessoas, principalmente daquelas que vivem em regiões altamente industrializadas. O Cd afeta a função placentária, podendo atravessar a barreira placentária e provocar distúrbios no desenvolvimento fetal. Pode, também, ser excretado pelo leite. O organismo é particularmente susceptível à exposição ao Cd no período perinatal. Foi estudado o efeito da intoxicação por Cd no epitélio do soalho da boca de ratos expostos a baixos níveis do metal na água de bebedouro, durante a lactação. As ratas receberam água ad libitum contendo 300 mg/l de CdCl2 durante toda a lactação. Os animais controle receberam um volume similar de água sem Cd. Os filhotes foram sacrificados por sobredosagem anestésica no 21° dia. As cabeças dos animais foram separadas, fixadas em solução de "alfac" (álcool, ácido acético e formaldeído) por 24 h, seccionadas seriadamente em planos frontais ao nível dos primeiros molares, e os cortes de 6 µm foram corados com hematoxilina-eosina. Foram estimados os parâmetros nucleares do epitélio, assim como os volumes citoplasmático e celular, a relação núcleo/citoplasma, as densidades numérica e superficial e a espessura epitelial. O peso corporal médio do filhote foi de 34,86 g no grupo controle e 18,56 g no tratado. Histologicamente, o epitélio dos animais tratados mostrou-se adelgaçado, constituído de células abundantes e menores. Neste experimento, o Cd ocasionou um quadro de hipotrofia epitelial, indicando uma ação direta nas células epiteliais da mucosa oral, além de retardar o desenvolvimento dos filhotes intoxicados

    Well Placement Optimization with the Covariance Matrix Adaptation Evolution Strategy and Meta-Models

    Get PDF
    International audienceThe amount of hydrocarbon recovered can be considerably increased by finding optimal placement of non-conventional wells. For that purpose, the use of optimization algorithms, where the objective function is evaluated using a reservoir simulator, is needed. Furthermore, for complex reservoir geologies with high heterogeneities, the optimization problem requires algorithms able to cope with the non regularity of the objective function. In this paper, we propose an optimization methodology for determining optimal well locations and trajectories based on the Covariance Matrix Adaptation - Evolution Strategy (CMA-ES) which is recognized as one of the most powerful derivative-free optimizers for continuous optimization. In addition, to improve the optimization procedure two new techniques are proposed: (1) Adaptive penalization with rejection in order to handle well placement constraints; (2) Incorporation of a meta-model, based on locally weighted regression, into CMA-ES, using an approximate stochastic ranking procedure, in order to reduce the number of reservoir simulations required to evaluate the objective function. The approach is applied to the PUNQ-S3 case and compared with a Genetic Algorithm (GA) incorporating the Genocop III technique for handling constraints. To allow a fair comparison, both algorithms are used without parameter tuning on the problem, standard settings are used for the GA and default settings for CMA-ES. It is shown that our new approach outperforms the genetic algorithm: it leads in general to both a higher net present value and a significant reduction in the number of reservoir simulations needed to reach a good well configuration. Moreover, coupling CMA-ES with a metamodel leads to further improvement, which was around 20% for the synthetic case in this study
    corecore