Procalcitonin kinetics in the first 48 hours of ICU admission is associated with higher mortality in critically ill patients with community-acquired pneumonia in a setting of high HIV prevalence

Background: Severe community acquired pneumonia (CAP) commonly results in ICU admission and is associated with significant morbidity and mortality. Procalcitonin (PCT) may assist risk stratification and prediction of aetiology but is not well studied in critically ill patients with a high HIV prevalence.Methods: A retrospective observational study of patients admitted to ICU with a clinical diagnosis of CAP was undertaken. PCT on admission and at 48 hours was evaluated as a predictor of ICU outcome and pneumonia aetiology.Results: A total of 100 patients were included; 62% were HIV positive. Overall ICU mortality was 61%. PCT at admission and 48 hours was not associated with any outcome variables. A significant association was found between mortality and patients whose PCT levels increased or remained >10 ng/ml at 48 hours, compared with those that remained unchanged or decreased (67% vs. 41% p = 0.018). The commonest aetiology identified was Mycobacterium tuberculosis (n = 18, 21.4%). Patients with admission PCT levels >10 ng/ml were more likely to have positive bacterial cultures (OR = 3.14; 95% CI 1.11–9.73).Conclusions: Increasing or persistently elevated PCT predicts a higher mortality in critically ill patients with CAP. This suggests PCT kinetics may be useful in risk stratifying patients with CAP at 48 hours. While positive bacterial cultures are more likely in patients with high admission PCT, this assay does not allow for decisions to be made on antimicrobial management and is of limited clinical utility in critically ill patients with a high HIV prevalence and CAP.Keywords: critical care, procalcitonin, intensive care, prognosis, severe community acquired pneumoni

Validating the utilisation of venous bicarbonate as a predictor of acute kidney injury in crush syndrome from sjambok injuries

Background. Crush injury secondary to sjambok beatings is a well-described phenomenon in southern Africa. Owing to a number of factors, it can result in acute kidney injury (AKI). In 1992, Muckart et al. described a risk stratification system using venous bicarbonate (VB) that can be used in the management of these patients.Objective. To validate this score in the modern era of AKI risk stratification.Methods. A retrospective study was performed on a local trauma database from June 2010 to December 2012. All patients with crush injury from sjambok/blunt instrument beatings were included in the analysis. VB was compared with the Kidney Disease Improving Global Outcomes scoring system for AKI. Serum base excess (BE) and creatine kinase were also examined as biomarkers. The endpoints were the need for renal replacement therapy (RRT) and mortality.Results. Three hundred and ten patients were included. The overall mortality rate was 1.9%, 14.8% of patients had AKI, and 3.9% required RRT. Both VB and BE performed well in RRT prediction, with areas under the receiver operating characteristic curve of 0.847 (95% confidence interval (CI) 0.756 - 0.938; p<0.001) and 0.871 (95% CI 0.795 - 0.947; p<0.001), respectively. The sensitivity and specificity of BE were 83.3% and 80.2% at an optimal cut-point of –7.25 mmol/L, while those of VB were 83.3% and 79.5% at an optimal cut-point of 18.85 mmol/L. VB was significantly different across the AKI risk groups (p<0.001), in keeping with the original Muckart risk stratification system.Conclusion. The risk stratification score using VB is valid and should continue to be used as a tool in the management of patients with sjambok injuries. BE performs well in predicting the need for RRT, with a value of <–7.25 mmol/L indicating severe injury

Crucial Physical Dependencies of the Core-Collapse Supernova Mechanism

We explore with self-consistent 2D F{\sc{ornax}} simulations the dependence of the outcome of collapse on many-body corrections to neutrino-nucleon cross sections, the nucleon-nucleon bremsstrahlung rate, electron capture on heavy nuclei, pre-collapse seed perturbations, and inelastic neutrino-electron and neutrino-nucleon scattering. Importantly, proximity to criticality amplifies the role of even small changes in the neutrino-matter couplings, and such changes can together add to produce outsized effects. When close to the critical condition the cumulative result of a few small effects (including seeds) that individually have only modest consequence can convert an anemic into a robust explosion, or even a dud into a blast. Such sensitivity is not seen in one dimension and may explain the apparent heterogeneity in the outcomes of detailed simulations performed internationally. A natural conclusion is that the different groups collectively are closer to a realistic understanding of the mechanism of core-collapse supernovae than might have seemed apparent.Comment: 25 pages; 10 figure

Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4

The performance of the jet trigger for the ATLAS detector during 2011 data taking

The performance of the jet trigger for the ATLAS detector at the LHC during the 2011 data taking period is described. During 2011 the LHC provided proton–proton collisions with a centre-of-mass energy of 7 TeV and heavy ion collisions with a 2.76 TeV per nucleon–nucleon collision energy. The ATLAS trigger is a three level system designed to reduce the rate of events from the 40 MHz nominal maximum bunch crossing rate to the approximate 400 Hz which can be written to offline storage. The ATLAS jet trigger is the primary means for the online selection of events containing jets. Events are accepted by the trigger if they contain one or more jets above some transverse energy threshold. During 2011 data taking the jet trigger was fully efficient for jets with transverse energy above 25 GeV for triggers seeded randomly at Level 1. For triggers which require a jet to be identified at each of the three trigger levels, full efficiency is reached for offline jets with transverse energy above 60 GeV. Jets reconstructed in the final trigger level and corresponding to offline jets with transverse energy greater than 60 GeV, are reconstructed with a resolution in transverse energy with respect to offline jets, of better than 4 % in the central region and better than 2.5 % in the forward direction

Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at sqrt [ s ] = 13TeV

A search for physics beyond the Standard Model, in final states with at least one high transverse momentum charged lepton (electron or muon) and two additional high transverse momentum leptons or jets, is performed using 3.2 fb−1 of proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015 at √s = 13 TeV. The upper end of the distribution of the scalar sum of the transverse momenta of leptons and jets is sensitive to the production of high-mass objects. No excess of events beyond Standard Model predictions is observed. Exclusion limits are set for models of microscopic black holes with two to six extra dimensions

Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at √s = 13TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions

Search for dark matter produced in association with a hadronically decaying vector boson in pp collisions at sqrt (s) = 13 TeV with the ATLAS detector

A search is presented for dark matter produced in association with a hadronically decaying W or Z boson using 3.2 fb−1 of pp collisions at View the MathML sources=13 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet compatible with a W or Z boson and with large missing transverse momentum are analysed. The data are consistent with the Standard Model predictions and are interpreted in terms of both an effective field theory and a simplified model containing dark matter