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Background: Evidence-based international expert consensus regarding anaesthetic practice in hip/knee arthroplasty surgery is needed for improved healthcare outcomes. Methods: The International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) systematic review, including randomised controlled and observational studies comparing neuraxial to general anaesthesia regarding major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, genitourinary, thromboembolic, neurological, infectious, and bleeding complications. Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, from 1946 to May 17, 2018 were queried. Meta-analysis and Grading of Recommendations Assessment, Development and Evaluation approach was utilised to assess evidence quality and to develop recommendations. Results: The analysis of 94 studies revealed that neuraxial anaesthesia was associated with lower odds or no difference in virtually all reported complications, except for urinary retention. Excerpt of complications for neuraxial vs general anaesthesia in hip/knee arthroplasty, respectively: mortality odds ratio (OR): 0.67, 95% confidence interval (CI): 0.57–0.80/OR: 0.83, 95% CI: 0.60–1.15; pulmonary OR: 0.65, 95% CI: 0.52–0.80/OR: 0.69, 95% CI: 0.58–0.81; acute renal failure OR: 0.69, 95% CI: 0.59–0.81/OR: 0.73, 95% CI: 0.65–0.82; deep venous thrombosis OR: 0.52, 95% CI: 0.42–0.65/OR: 0.77, 95% CI: 0.64–0.93; infections OR: 0.73, 95% CI: 0.67–0.79/OR: 0.80, 95% CI: 0.76–0.85; and blood transfusion OR: 0.85, 95% CI: 0.82–0.89/OR: 0.84, 95% CI: 0.82–0.87. Conclusions: Recommendation: primary neuraxial anaesthesia is preferred for knee arthroplasty, given several positive postoperative outcome benefits; evidence level: low, weak recommendation. Recommendation: neuraxial anaesthesia is recommended for hip arthroplasty given associated outcome benefits; evidence level: moderate-low, strong recommendation. Based on current evidence, the consensus group recommends neuraxial over general anaesthesia for hip/knee arthroplasty. Trial registry number: PROSPERO CRD42018099935. © 2019 British Journal of Anaesthesia

International audience; In this paper, we are interested in the study of the ballasted track and specially in two main topics: the mechanisms of degradation in the medium-to-long term and the maintenance of the ballast layer. Both an experimental and a numerical approach have been developed. Numerical simulations are performed using discrete element methods and are validated through comparisons with reference experiments at reduced scale. This principle is the basis of the studies undertaken.

The control of railway rolling noise requires a reduction in wheel and track noise emission. In this paper, a parametric study of the possible minimization of the track sound power is presented. In an initial global approach, a number of potential variations in track parameters are assessed in terms of their likely effect on rolling noise. From this, two main themes are selected for deeper study by use of TWINS model. The first parameter considered is the stiffness and damping of the rail-pad. By reducing the pad stiffness, the noise radiation from the sleeper is reduced but that from the rail is increased, and vice versa. An optimum is found when the rail and sleeper components are equal, for which the track radiation is a minimum. Starting from one existing track design, this optimum pad stiffness has been derived for an example wheel. The second area investigated is the increase of the attenuation rate of rail vibrations by the addition of damping measures. The implementation of dynamic absorbers with a mass of 5 kg every sleeper bay (0.6 m) leads to predicted reductions of track radiation of 2 dB(A) if the rail-pad stiffness is already optimal. For softer pads a larger reduction has been found, but the total effect is less than the combined effect of first changing to the optimum pad stiffness and then adding absorbers. Globally, for ballasted track with bibloc concrete sleepers, a 2-6 dB(A) reduction in track sound power can be expected through a rail-pad optimization and/or the implementation of dynamic absorbers on the rail.