86 research outputs found
Activation of coagulation and fibrinolysis in acute respiratory distress syndrome : A prospective pilot study
Funding Information: The study was supported by grant ZP 10/2013 from Rigas Stradins University. Publisher Copyright: © 2016 Ozolina, Sarkele, Sabelnikovs, Skesters, Jaunalksne, Serova, Ievins, Bjertnaes and Vanags.Introduction: Coagulation and fibrinolysis remain sparsely addressed with regards to acute respiratory distress syndrome (ARDS). We hypothesized that ARDS development might be associated with changes in plasma coagulation and fibrinolysis. Our aim was to investigate the relationships between ARDS diagnosis and plasma concentrations of tissue factor (TF), tissue plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) in mechanically ventilated patients at increased risk of developing ARDS. Materials and methods: We performed an ethically approved prospective observational pilot study. Inclusion criteria were patients with PaO 2 /FiO 2 < 300 mmHg admitted to the intensive care unit (ICU) for mechanical ventilation for 24 h, or more, because of one or more disease conditions associated with increased risk of developing ARDS. Exclusion criteria were age below 18 years; cardiac disease. We sampled plasma prospectively and compared patients who developed ARDS with those who did not using descriptive statistics and chi-square analysis of baseline demographical and clinical data. We also analyzed plasma concentrations of TF, t-PA, and PAI-1 at inclusion (tissue) and on third (T 3 ) and seventh day (T 7 ) of the ICU stay with non-parametric statistics inclusive their sensitivity and specificity associated with the development of ARDS using receiver operating characteristic curve analysis. Statistical significance: p < 0.05. Results: Of 24 patients at risk, 6 developed mild ARDS and 4 of each moderate or severe ARDS, respectively, 3 ± 2 (mean ± SD) days after inclusion. Median plasma concentrations of TF and PAI-1 were significantly higher at T7 in patients with ARDS, as compared to non-ARDS. Simultaneously, we found moderate correlations between plasma concentrations of TF and PAI-1, TF and PaO 2 /FiO 2 , and positive end-expiratory pressure and TF. TF plasma concentration was associated with ARDS with 71% sensitivity and 100% specificity, a cut off level of 145 pg/ml and AUC 0.78, p = 0.02. PAI-1 displayed 64% sensitivity and 100% specificity with a cut off concentration of 117.5 pg/ml and AUC 0.77, p = 0.02. t-PA did not change significantly during the observation time. Conclusion: This pilot study showed that increased plasma concentrations of TF and PAI-1 might support ARDS diagnoses in mechanically ventilated patients after 7 days in ICU.publishersversionPeer reviewe
The effect of alcohol consumption on the risk of ARDS: a systematic review and meta-analysis
BACKGROUND: To conduct a systematic review and meta-analysis evaluating the association between alcohol consumption and the risk of ARDS in adults.
METHODS: Medline, EMBASE and Web of Science were searched to identify observational studies evaluating the association between prior alcohol intake and the occurrence of ARDS among adults, published between 1985 and 2015 and with no language restriction. Reference lists were also screened. Demographic baseline data were extracted independently by two reviewers and random-effects meta-analyses were used to estimate pooled effect sizes with 95% confidence intervals. Subgroup analyses were used to explore heterogeneity.
RESULTS: Seventeen observational studies (177,674 people) met the inclusion criteria. Metaanalysis of 13 studies showed that any measure of high relative to low alcohol consumption was associated with a significantly increased risk of ARDS (OR, 1.89; 95% CI, 1.45-2.48; I² = 48%; 13 studies); no evidence of publication bias was seen (P = .150). Sensitivity analyses indicated that this association was attributable primarily to an effect of a history of alcohol abuse (OR, 1.90; 95% CI, 1.40-2.60; 10 studies). Also, subgroup analyses identified that heterogeneity was explained by predisposing condition (trauma, sepsis/septic shock, pneumonia; P = .003).
CONCLUSIONS: Chronic high alcohol consumption significantly increases the risk of ARDS. This finding suggests that patients admitted to hospital should be screened for chronic alcohol use
Chalk-steel Interface testing for marine energy foundations
The Energy Technology Partnership (ETP) and Lloyd’s Register EMEA are gratefully acknowledged for the funding of this project. The authors would also like to acknowledge the support of the European Regional Development Fund (ERDF) SMART Centre at the University of Dundee that allowed purchase of the equipment used during this study. The views expressed are those of the authors alone, and do not necessarily represent the views of their respective companies or employing organizations.Peer reviewedPostprin
Towards the prevention of acute lung injury: a population based cohort study protocol
<p>Abstract</p> <p>Background</p> <p>Acute lung injury (ALI) is an example of a critical care syndrome with limited treatment options once the condition is fully established. Despite improved understanding of pathophysiology of ALI, the clinical impact has been limited to improvements in supportive treatment. On the other hand, little has been done on the prevention of ALI. Olmsted County, MN, geographically isolated from other urban areas offers the opportunity to study clinical pathogenesis of ALI in a search for potential prevention targets.</p> <p>Methods/Design</p> <p>In this population-based observational cohort study, the investigators identify patients at high risk of ALI using the prediction model applied within the first six hours of hospital admission. Using a validated system-wide electronic surveillance, Olmsted County patients at risk are followed until ALI, death or hospital discharge. Detailed in-hospital (second hit) exposures and meaningful short and long term outcomes (quality-adjusted survival) are compared between ALI cases and high risk controls matched by age, gender and probability of developing ALI. Time sensitive biospecimens are collected for collaborative research studies. Nested case control comparison of 500 patients who developed ALI with 500 matched controls will provide an adequate power to determine significant differences in common hospital exposures and outcomes between the two groups.</p> <p>Discussion</p> <p>This population-based observational cohort study will identify patients at high risk early in the course of disease, the burden of ALI in the community, and the potential targets for future prevention trials.</p
Shearing Behavior Of Curved Interfaces
The frictional behavior of soil-construction material interfaces is of significant importance in geotechnical engineering applications such as retaining structures, pile foundations, geosynthetic liners, and trenchless technologies. Since most failures initiate and develop on the interfaces, special attention is required to predict the capacity of these weak planes in the particular application.
Pipe-jacking and microtunneling technologies are being more widely used over the past decade and there is significant interest to predict the jacking forces and jacking distances achievable in order to achieve more efficient design and construction. This study focuses on the evaluation of the frictional characteristics and factors affecting the shear strength of pipe-soil interfaces. Eight different pipes made from fiber reinforced polymer (FRP), polycrete, steel, concrete, and vitrified clay were tested in the experimental program.
For this purpose, a new apparatus was designed to conduct conventional interface direct shear testing on pipes of different curvature. This device allows coupons cut from actual conduits and pipes to be tested in the laboratory under controlled conditions. The apparatus includes a double-wall shear box, the inner wall of which is interchangeable to allow for testing against surfaces of different curvatures. By considering a narrow width section, the circular interface of pipes was approximated with a surface along the axial direction and the boundary is defined by the inner box.
Roughness tests were performed using a stylus profilometer to quantify the surface characteristics of the individual pipes and relate these to the interface shear behavior. The surface topography showed different degrees of variability for the different pipes. To extend the range of roughness values tested and force the failure to occur in the particulate media adjacent to the interface, two artificial pipe surfaces were created using rough sandpapers.
Interface shear tests were performed using the new apparatus with air-pluviated dense specimens of Ottawa 20/30 sand. Additional tests were performed using Atlanta blasting sand to evaluate the effect of particle angularity. The effect of normal stress and relative density were also examined. The interface strength was shown to increase with surface roughness and finally reach a constant value above a certain critical roughness value, which corresponded to the internal strength of the soil itself. This represented the failure location moving from the interface into the soil adjacent to the interface. Both the strength and the shearing mechanism were thus affected by the surface topography. It was also shown that the interface shear strength was affected by particle angularity, relative density and normal stress.M.S.Committee Chair: Frost, David; Committee Member: Mayne, Paul; Committee Member: Rix, Glen
Sequence stratigraphy of Miocene sequences Kw2a and m5.4, New Jersey: onshore to offshore correlations
I evaluated the upper lower Miocene Kw2a sequence in onshore New Jersey coastal plain coreholes and nearshore wells and its relationship to composite sequence m5.4 on the New Jersey continental shelf. I used Ocean Drilling Program Leg 174AX Cape May Zoo (CMZ) and Ocean View (OV) corehole and well log data to construct the anatomy of composite Kw2a sequence by integrating lithologic changes, grain size data, gamma ray logs, and benthic foraminiferal biofacies and paleodepths in a sequence stratigraphic framework. I identified 3 higher order sequences (Kw2a1, Kw2a2, and Kw2a3) and stratal boundaries (transgressive surfaces [TS] and maximum flooding surfaces [MFS]) within the composite Kw2a sequence. A thin, deepening upward LST is tentatively identified only at the base of the Kw2a1 higher order sequence at both sites. Mud dominant, deepening and fining upward TST’s are found in all 3 higher order sequences. MFS are associated with mud and Uvigerina spp. peaks and are overlain by, sandy coarsening and shallowing upward HST’s. To test the physical correlation between onshore-nearshore and middle shelf systems, I identified Kw2a and higher order sequences in other ODP Leg 150A, 174AX, and U.S.G.S onshore and nearshore wells using gamma ray logs. I correlated gamma ray logs of the composite Kw2a sequence to onshore [Atlantic City (AC)] and nearshore wells (ACOW-1, 2, AMCOR-6011) and traced the Kw2a sequence on seismic profiles crossing these sites. I projected other onshore cores and logs to nearby seismic profiles. I traced the composite Kw2a sequence on seismic profiles directly to IODP Expedition 313 coreholes where I demonstrate that the composite Kw2a sequence is physically equivalent to composite m5.4 sequence.M.S.Includes bibliographical referencesby Turan Iscime
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