Patient-maintained sedation for oral surgery using a target-controlled infusion of propofol - a pilot study

OBJECTIVE: To assess the safety and efficacy of a new patient-maintained propofol system for conscious sedation in dentistry. DESIGN: Prospective clinical trial SETTING: Department of Sedation, Glasgow Dental Hospital and School, 2001 SUBJECTS AND METHODS: Patients scheduled for oral surgery with conscious sedation. Exclusions included ASA IV -V, inability to use the handset, opioid use and severe respiratory disease. INTERVENTIONS: Patients were given intravenous propofol to a level of 1.0 microg/ml (reducing from 1.5 microg/ml) using a target controlled infusion system, they then controlled their sedation level by double-clicking a handset which on each activation increased the propofol concentration by 0.2 microg/ml. MAIN OUTCOME MEASURES: Oxygen saturation, patient satisfaction, and surgeon satisfaction. RESULTS: Twenty patients were recruited, 16 female and four male. Nineteen patients completed sedation and treatment successfully. Mean lowest oxygen saturation was 94%. No patients were over-sedated. All patients successfully used the system to maintain a level of sedation adequate for their comfort. Patient and surgeon satisfaction were consistently high. CONCLUSIONS: Initial experience with this novel system has confirmed safety, patient satisfaction and surgeon satisfaction

Elastic models for the non-Arrhenius viscosity of glass-forming liquids

This paper first reviews the shoving model for the non-Arrhenius viscosity of viscous liquids. According to this model the main contribution to the activation energy of a flow event is the energy needed for molecules to shove aside the surrounding, an energy which is proportional to the instantaneous shear modulus of the liquid. Data are presented supporting the model. It is shown that the fractional Debye-Stokes-Einstein relation, that quantitatively expresses the frequently observed decoupling of, e.g., conductivity from viscous flow, may be understood within the model. The paper goes on to review several related explanations for the non-Arrhenius viscosity. Most of these are also "elastic models," i.e., they express the viscosity activation energy in terms of short-time elastic properties of the liquid. Finally, two new arguments for elastic models are given, a general solid-state defect argument and an Occam's razor type argument

Why are glass-forming liquids non-Arrhenius?

A major mystery of glass-forming liquids is the non-Arrhenius temperature-dependence of the average relaxation time. This paper briefly reviews the classical phenomenological models for this phenomenon - the free-volume model and the entropy model - and critiques against these models. We then discuss a recent model [Dyre, Olsen, and Christensen, Phys. Rev. B 53, 2171 (1996)] according to which the activation energy for the average relaxation time is determined by the work done in shoving aside the surrounding liquid to create space needed for a flow event. In this model the non-Arrhenius temperature-dependence is a consequence of the fact that the instantaneous (infinite-frequency) shear modulus increases upon cooling.Comment: 18 pages, plain RevTex file, no figure

Dorstone Hill: A Neolithic timescape

Studies of early fourth-millennium BC Britain have typically focused on the Early Neolithic sites of Wessex and Orkney; what can the investigation of sites located in areas beyond these core regions add? The authors report on excavations (2011-2019) at Dorstone Hill in Herefordshire, which have revealed a remarkable complex of Early Neolithic monuments: three long barrows constructed on the footprints of three timber buildings that had been deliberately burned, plus a nearby causewayed enclosure. A Bayesian chronological model demonstrates the precocious character of many of the site's elements and strengthens the evidence for the role of tombs and houses/halls in the creation and commemoration of foundational social groups in Neolithic Britain

Mid-esophagus unresectable cancer treated with a low cost stent. First experience

<p>Abstract</p> <p>Background</p> <p>In the cancer of the esophagus, with recent technologic advances, self-expanding metal stents (SEMS) are at the forefront of the armamentarium for re-establishing luminal patency. Weighed against the numerous advantages of stents are the import conditions and the cost. In light of this, we tested new low cost prostheses having the basic needs and characteristics to aim a significant benefit to poor people having advanced esophageal cancer, in a Brazilian regional public hospital.</p> <p>Methods</p> <p>This initial experience included fifteen patients (eleven men and four women, 55 ± 6.17 years old), presenting esophageal cancer, located at the medium third of the thoracic esophagus, extending for 5.5-8 cm long, not suitable for surgical procedure because they had been staged on fourth grade of the disease, two of them having fistula communicating esophagus to respiratory tree. The stents were placed under endoscopic and fluoroscopic guidance, after attempting an esophageal dilatation. An appropriate covered stent was then deployed, twelve of 10 cm and three of 13 cm in length. A chest X-ray was done 2 h after the procedure and a barium swallow was performed within 12 hours. Seven days and monthly until complete a six month follow-up after the procedure the patients were questioned about presence of pain, regurgitation, heartburn, cough, and their alimentary behavior.</p> <p>Results</p> <p>There were no severe complications and transient mild chest pain resolved until the seventh day after the stent deployment. Chest X-ray demonstrated expansion of the stent in all patients. In 2 cases of fistula, a barium swallow showed its complete sealing. The completion of the proposed follow-up was not achieved in three cases, limited by the patient's death until the third month, due to cancer progression. Recurrent dysphagia to paste food accounted for by tumor overgrowth proximal or distal to the stent and stent migration were not observed in the series.</p> <p>Conclusions</p> <p>The new low cost endoprostheses is effective and forthcoming increased experience and prospective trials including questionnaires to analyze quality of life will allow for more informed decisions tailoring to a particular patient situation or to unexpected complications.</p

Building operational research capacity in the Pacific

Operational research (OR) in public health aims to investigate strategies, interventions, tools or knowledge that can enhance the quality, coverage, effectiveness or performance of health systems. Attention has recently been drawn to the lack of OR capacity in public health programmes throughout the Pacific Islands, despite considerable investment in implementation. This lack of ongoing and critical reflection may prevent health programme staff from understanding why programme objectives are not being fully achieved, and hinder long-term gains in public health. The International Union Against Tuberculosis and Lung Disease (The Union) has been collaborating with Pacific agencies to conduct OR courses based on the training model developed by The Union and Médecins Sans Frontières Brussels-Luxembourg in 2009. The first of these commenced in 2011 in collaboration with the Fiji National University, the Fiji Ministry of Health, the World Health Organization and other partners. The Union and the Secretariat of the Pacific Community organised a second course for participants from other Pacific Island countries and territories in 2012, and an additional course for Fijian participants commenced in 2013. Twelve participants enrolled in each of the three courses. Of the two courses completed by end 2013, 18 of 24 participants completed their OR and submitted papers by the course deadline, and 17 papers have been published to date. This article describes the context, process and outputs of the Pacific courses, as well as innovations, adaptations and challenges

Building operational research capacity in the Pacific

Operational research (OR) in public health aims to investigate strategies, interventions, tools or knowledge that can enhance the quality, coverage, effectiveness or performance of health systems. Attention has recently been drawn to the lack of OR capacity in public health programmes throughout the Pacific Islands, despite considerable investment in implementation. This lack of ongoing and critical reflection may prevent health programme staff from understanding why programme objectives are not being fully achieved, and hinder long-term gains in public health. The International Union Against Tuberculosis and Lung Disease (The Union) has been collaborating with Pacific agencies to conduct OR courses based on the training model developed by The Union and Médecins Sans Frontières Brussels-Luxembourg in 2009. The first of these commenced in 2011 in collaboration with the Fiji National University, the Fiji Ministry of Health, the World Health Organization and other partners. The Union and the Secretariat of the Pacific Community organised a second course for participants from other Pacific Island countries and territories in 2012, and an additional course for Fijian participants commenced in 2013. Twelve participants enrolled in each of the three courses. Of the two courses completed by end 2013, 18 of 24 participants completed their OR and submitted papers by the course deadline, and 17 papers have been published to date. This article describes the context, process and outputs of the Pacific courses, as well as innovations, adaptations and challenges

Antibiotic Review Kit for Hospitals (ARK-Hospital): study protocol for a stepped-wedge cluster-randomised controlled trial.

BACKGROUND: To ensure patients continue to get early access to antibiotics at admission, while also safely reducing antibiotic use in hospitals, one needs to target the continued need for antibiotics as more diagnostic information becomes available. UK Department of Health guidance promotes an initiative called 'Start Smart then Focus': early effective antibiotics followed by active 'review and revision' 24-72 h later. However in 2017, < 10% of antibiotic prescriptions were discontinued at review, despite studies suggesting that 20-30% of prescriptions could be stopped safely. METHODS/DESIGN: Antibiotic Review Kit for Hospitals (ARK-Hospital) is a complex 'review and revise' behavioural intervention targeting healthcare professionals involved in antibiotic prescribing or administration in inpatients admitted to acute/general medicine (the largest consumers of non-prophylactic antibiotics in hospitals). The primary study objective is to evaluate whether ARK-Hospital can safely reduce the total antibiotic burden in acute/general medical inpatients by at least 15%. The primary hypotheses are therefore that the introduction of the behavioural intervention will be non-inferior in terms of 30-day mortality post-admission (relative margin 5%) for an acute/general medical inpatient, and superior in terms of defined daily doses of antibiotics per acute/general medical admission (co-primary outcomes). The unit of observation is a hospital organisation, a single hospital or group of hospitals organised with one executive board and governance framework (National Health Service trusts in England; health boards in Northern Ireland, Wales and Scotland). The study comprises a feasibility study in one organisation (phase I), an internal pilot trial in three organisations (phase II) and a cluster (organisation)-randomised stepped-wedge trial (phase III) targeting a minimum of 36 organisations in total. Randomisation will occur over 18 months from November 2017 with a further 12 months follow-up to assess sustainability. The behavioural intervention will be delivered to healthcare professionals involved in antibiotic prescribing or administration in adult inpatients admitted to acute/general medicine. Outcomes will be assessed in adult inpatients admitted to acute/general medicine, collected through routine electronic health records in all patients. DISCUSSION: ARK-Hospital aims to provide a feasible, sustainable and generalisable mechanism for increasing antibiotic stopping in patients who no longer need to receive them at 'review and revise'. TRIAL REGISTRATION: ISRCTN Current Controlled Trials, ISRCTN12674243 . Registered on 10 April 2017

Population and labour force projections for 27 European countries, 2002-052: impact of international migration on population ageing: Projections de population et de population active pour 27 pays européens 2002-052: impact de la migration internationale sur le vieillissement de la population

Population and labour force projections are made for 27 selected European countries for 2002-052, focussing on the impact of international migration on population and labour force dynamics. Starting from single scenarios for fertility, mortality and economic activity, three sets of assumptions are explored regarding migration flows, taking into account probable policy developments in Europe following the enlargement of the EU. In addition to age structures, various support ratio indicators are analysed. The results indicate that plausible immigration cannot offset the negative effects of population and labour force ageing

Anomalous accelerations in spacecraft flybys of the Earth

[EN] The flyby anomaly is a persistent riddle in astrodynamics. Orbital analysis in several flybys of the Earth since the Galileo spacecraft flyby of the Earth in 1990 have shown that the asymptotic post-encounter velocity exhibits a difference with the initial velocity that cannot be attributed to conventional effects. To elucidate its origin, we have developed an orbital program for analyzing the trajectory of the spacecraft in the vicinity of the perigee, including both the Sun and the Moon¿s tidal perturbations and the geopotential zonal, tesseral and sectorial harmonics provided by the EGM96 model. The magnitude and direction of the anomalous acceleration acting upon the spacecraft can be estimated from the orbital determination program by comparing with the trajectories fitted to telemetry data as provided by the mission teams. This acceleration amounts to a fraction of a mm/s2 and decays very fast with altitude. 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