"Low-dose"-Droperidol-Gabe bei Kindern: "Rescue"-Therapie gegen persistierende postoperative Übelkeit und Erbrechen

Zusammenfassung: Hintergrund: Persistierende postoperative Übelkeit und Erbrechen ("postoperative nausea and vomiting", PONV) trotz Prophylaxe ist in der Kinderanästhesie ein wichtiges Problem. In der vorgestellten Studie wurde untersucht, ob die "Low-dose"-Droperidol-Gabe (10µg/kgKG) als Rescue-Therapie bei persistierender PONV effektiv ist. Patienten und Methoden: Im elektronischen Archiv der Anästhesieabteilung der Universitäts-Kinderkliniken Zürich wurden von 2004 bis 2009 alle Patienten herausgefiltert, die im Aufwachraum Droperidol erhalten hatten. Es wurde überprüft, ob Low-dose-Droperidol gegen persistierende PONV wirksam ist und ob unerwünschte Nebenwirkungen aufgetreten sind. Ergebnisse: Daten von 144Patienten im Alter von 12,3Jahren [Interquartilabstand (IQR) 9,5 bis 15,2Jahre] konnten für die Untersuchung verwendet werden. Bei 128Patienten (89%) war die Rescue-Therapie mit Low-dose-Droperidol effektiv. Bei 16Patienten (11%) erfolgte keine Besserung. Sedation war die einzige beobachtete Nebenwirkung bei 39Patienten (27%). Schlussfolgerung: Die Gabe von Low-dose-Droperidol erwies sich als effektive Rescue-Therapie bei Kindern, bei denen trotz prophylaktischer antiemetischer Therapie PONV persistiert

Intrathekale Opioidmedikation zur perioperativen Analgesie bei schwer behinderten Kindern mit Wirbelsäulenoperationen

Zusammenfassung: Hintergrund: An gesunden Kindern konnte gezeigt werden, dass intrathekal verabreichte Opioide eine sichere und effektive perioperative Analgesie bei wirbelsäulenchirurgischen Eingriffen ermöglichen. Das Ziel der vorliegenden Untersuchung ist es, ihre Anwendbarkeit bei schwer- und schwerstbehinderten Kindern für wirbelsäulenchirurgische Eingriffe zu überprüfen. Methode: Mit Zustimmung der lokalen Ethikkommission wurden Patienten vom Status3 und 4 der Klassifikation der American Society of Anesthesiologists (ASA), die sich einem wirbelsäulenchirurgischen Eingriff unterziehen mussten, retrospektiv untersucht. Zusätzlich zur Allgemeinanästhesie mit Sevofluran oder i.v.-verabreichtem Propofol erhielten die Patienten vor der Operation 20µg/kgKG Morphin und 1,5µg/kgKG Sufentanil intrathekal. Nach Beendigung des Eingriffs wurde eine Nalbuphindauerinfusion gestartet. Der Bedarf an zusätzlichen intra- und postoperativen Analgetika, der Zeitpunkt der Extubation, die postoperativen Schmerz-Scores und die arteriellen Kohlendioxidpartialdruck- (paCO2)-Werte sowie das Auftreten unerwünschter Nebenwirkungen wurden untersucht. Ergebnisse: Es wurden 28Patienten im Alter von 2,8 bis 18,5Jahren (Median 11,6Jahre) untersucht. Unmittelbar im OP konnten 17Patienten extubiert werden; bei 11Patienten entschied man sich zu einer verzögerten Extubation. Bis auf einen Patienten mit postoperativer Massivtransfusion konnten alle innerhalb von 24h extubiert werden. Eine adäquate postoperative Analgesie mit Schmerz-Scores ≤3 wurde mithilfe der Kombination von intrathekal verabreichten Opioiden mit Nalbuphin postoperativ bei 26 von 28Patienten (93%) erreicht. Bei 2Patienten war der Wechsel auf eine i.v.-Morphin-Gabe erforderlich. Postoperative Übelkeit und Erbrechen ("postoperative nausea and vomiting", PONV), Pruritus und leichte Hypoventilation mit paCO2-Werten zwischen 5,2 bis 9,7kPa (Median 6,3kPa) waren die beobachteten Nebenwirkungen. Schlussfolgerung: Der Einsatz intrathekal verabreichter Opioide, ergänzt durch eine postoperative Nalbuphininfusion, erlaubt in den allermeisten Fällen eine frühzeitige Extubation ohne persistierende Atemdepression und ist eine praktikable sowie effektive Methode zur postoperativen Analgesie bei schwer behinderten Kindern nach wirbelsäulenchirurgischen Eingriffe

Late growth stages and post-growth diffusion in organic epitaxy: PTCDA on Ag(111)

The late growth stages and the post-growth diffusion of crystalline organic thin films have been investigated for 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) on Ag(111), a model system in organic epitaxy. In situ x-ray measurements at the anti-Bragg point during the growth show intensity oscillations followed by a time-independent intensity which is independent of the growth temperature. At T > 350 K, the intensity increases after growth up to a temperature-dependent saturation value due to a post-growth diffusion process. The time-independent intensity and the subsequent intensity recovery have been reproduced by models based on the morphology change as a function of the growth temperature. The morphology found after the post-growth diffusion processes has been studied by specular rod measurements.Comment: 9 pages, 8 figures, accepted for publication in Surface Scienc

Mean flow and spiral defect chaos in Rayleigh-Benard convection

We describe a numerical procedure to construct a modified velocity field that does not have any mean flow. Using this procedure, we present two results. Firstly, we show that, in the absence of mean flow, spiral defect chaos collapses to a stationary pattern comprising textures of stripes with angular bends. The quenched patterns are characterized by mean wavenumbers that approach those uniquely selected by focus-type singularities, which, in the absence of mean flow, lie at the zig-zag instability boundary. The quenched patterns also have larger correlation lengths and are comprised of rolls with less curvature. Secondly, we describe how mean flow can contribute to the commonly observed phenomenon of rolls terminating perpendicularly into lateral walls. We show that, in the absence of mean flow, rolls begin to terminate into lateral walls at an oblique angle. This obliqueness increases with Rayleigh number.Comment: 14 pages, 19 figure

Longitudinal study of informed consent in innovative therapy research: experience and provisional recommendations from a multicenter trial of intracerebral grafting.

BACKGROUND: There is an urgent need to assess and improve the consent process in clinical trials of innovative therapies for neurodegenerative disorders. METHODS: We performed a longitudinal study of the consent of Huntington's disease patients during the Multicenter Fetal Cell Intracerebral Grafting Trial in Huntington's Disease (MIG-HD) in France and Belgium. Patients and their proxies completed a consent questionnaire at inclusion, before signing the consent form and after one year of follow-up, before randomization and transplantation. The questionnaire explored understanding of the protocol, satisfaction with the information delivered, reasons for participating in the trial and expectations regarding the transplant. Forty-six Huntington's disease patients and 27 proxies completed the questionnaire at inclusion, and 27 Huntington's disease patients and 16 proxies one year later. RESULTS: The comprehension score was high and similar for Huntington's disease patients and proxies at inclusion (72.6% vs 77.8%; P > 0.1) but only decreased in HD patients after one year. The information satisfaction score was high (73.5% vs 66.5%; P > 0.1) and correlated with understanding in both patients and proxies. The motivation and expectation profiles were similar in patients and proxies and remained unchanged after one year. CONCLUSIONS: Cognitively impaired patients with Huntington's disease were capable of consenting to participation in this trial. This consent procedure has presumably strengthened their understanding and should be proposed before signing the consent form in future gene or cell therapy trials for neurodegenerative disorders. Because of the potential cognitive decline, proxies should be designated as provisional surrogate decision-makers, even in competent patients

Oscillations and waves in solar spicules

Since their discovery, spicules have attracted increased attention as energy/mass bridges between the dense and dynamic photosphere and the tenuous hot solar corona. Mechanical energy of photospheric random and coherent motions can be guided by magnetic field lines, spanning from the interior to the upper parts of the solar atmosphere, in the form of waves and oscillations. Since spicules are one of the most pronounced features of the chromosphere, the energy transport they participate in can be traced by the observations of their oscillatory motions. Oscillations in spicules have been observed for a long time. However the recent high-resolutions and high-cadence space and ground based facilities with superb spatial, temporal and spectral capacities brought new aspects in the research of spicule dynamics. Here we review the progress made in imaging and spectroscopic observations of waves and oscillations in spicules. The observations are accompanied by a discussion on theoretical modelling and interpretations of these oscillations. Finally, we embark on the recent developments made on the presence and role of Alfven and kink waves in spicules. We also address the extensive debate made on the Alfven versus kink waves in the context of the explanation of the observed transverse oscillations of spicule axes

Bevacizumab in temozolomide refractory high-grade gliomas: single-centre experience and review of the literature

BACKGROUND: Despite multidisciplinary treatment approaches, the prognosis for patients with high-grade glioma (HGG) is poor, with a median overall survival (OS) of 14.6 months for glioblastoma multiforme (GB). As high levels of vascular endothelial growth factor A (VEGF) are found in HGG, targeted anti-antiangiogenic therapy using the humanized monoclonal antibody bevacizumab (BEV) was studied in a series of clinical trials. Still, the discrepancy of BEV's efficacy with regard to initial clinical and radiological response and its reported failure to prolong survival remains to be explained. Here, we illustrate the effectiveness of BEV in recurrent HGG by summarizing our single-centre experience. METHODS: We have retrospectively investigated the effect of BEV in temozolomide refractory HGG in 39 patients treated at the University Hospital of Ulm, Germany. RESULTS: Median duration of BEV treatment was 12.5 weeks; 23% of patients received BEV for more than 6 months and 15% for more than 1 year, until clinical or radiological tumour progression led to discontinuation. Furthermore, Karnofsky performance status increased in 30.6% and steroid dose decreased in 39% of all patients. CONCLUSIONS: The review of literature reveals that phase II and III studies support BEV as an effective therapy in recurrent HGG, at least with regard to progression-free survival (PFS), but landmark phase III trials failed to prove benefit concerning OS. Here, we discuss reasons that may account for this observation. We conclude that prolonging PFS with maintenance of neurological function and personal and economic independency justifies the off-label use of BEV

Shadowing in Inelastic Scattering of Muons on Carbon, Calcium and Lead at Low XBj

Nuclear shadowing is observed in the per-nucleon cross-sections of positive muons on carbon, calcium and lead as compared to deuterium. The data were taken by Fermilab experiment E665 using inelastically scattered muons of mean incident momentum 470 GeV/c. Cross-section ratios are presented in the kinematic region 0.0001 < XBj <0.56 and 0.1 < Q**2 < 80 GeVc. The data are consistent with no significant nu or Q**2 dependence at fixed XBj. As XBj decreases, the size of the shadowing effect, as well as its A dependence, are found to approach the corresponding measurements in photoproduction.Comment: 22 pages, incl. 6 figures, to be published in Z. Phys.

Bose-Einstein Correlations of Neutral and Charged Pions in Hadronic Z Decays

Bose-Einstein correlations of both neutral and like-sign charged pion pairs are measured in a sample of 2 million hadronic Z decays collected with the L3 detector at LEP. The analysis is performed in the four-momentum difference range 300 MeV < Q < 2 GeV. The radius of the neutral pion source is found to be smaller than that of charged pions. This result is in qualitative agreement with the string fragmentation model

A framework for the cross-sectoral integration of multi-model impact projections: land use decisions under climate impacts uncertainties

Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impactmodel setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making. Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop- and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making