Evaluation of drug administration errors in a teaching hospital

<p>Abstract</p> <p>Background</p> <p>Medication errors can occur at any of the three steps of the medication use process: prescribing, dispensing and administration. We aimed to determine the incidence, type and clinical importance of drug administration errors and to identify risk factors.</p> <p>Methods</p> <p>Prospective study based on disguised observation technique in four wards in a teaching hospital in Paris, France (800 beds). A pharmacist accompanied nurses and witnessed the preparation and administration of drugs to all patients during the three drug rounds on each of six days per ward. Main outcomes were number, type and clinical importance of errors and associated risk factors. Drug administration error rate was calculated with and without wrong time errors. Relationship between the occurrence of errors and potential risk factors were investigated using logistic regression models with random effects.</p> <p>Results</p> <p>Twenty-eight nurses caring for 108 patients were observed. Among 1501 opportunities for error, 415 administrations (430 errors) with one or more errors were detected (27.6%). There were 312 wrong time errors, ten simultaneously with another type of error, resulting in an error rate without wrong time error of 7.5% (113/1501). The most frequently administered drugs were the cardiovascular drugs (425/1501, 28.3%). The highest risks of error in a drug administration were for dermatological drugs. No potentially life-threatening errors were witnessed and 6% of errors were classified as having a serious or significant impact on patients (mainly omission). In multivariate analysis, the occurrence of errors was associated with drug administration route, drug classification (ATC) and the number of patient under the nurse's care.</p> <p>Conclusion</p> <p>Medication administration errors are frequent. The identification of its determinants helps to undertake designed interventions.</p

An andesitic source for Jack Hills zircon supports onset of plate tectonics in the Hadean

© 2020 Crown. The composition and origin of Earth’s early crust remains hotly debated. Here we use partition coefficients to invert the trace element composition of 4.3–3.3 Gyr Jack Hills zircons to calculate the composition of the melts from which they crystallised. Using this approach, the average SiO2 content of these melts was 59 ± 6 wt. % with Th/Nb, Dy/Yb and Sr/Y ratios of 2.7 ± 1.9, 0.9 ± 0.2 and 1.6 ± 0.7, respectively. Such features strongly indicate that the protolith for the Jack Hills zircons was not an intra-plate mafic rock, nor a TTG (tondjhemite-tonalite-granodiorite) or a Sudbury-like impact melt. Instead, the inferred equilibrium melts are much more similar to andesites formed in modern subduction settings. We find no evidence for any secular variation between 4.3 and 3.3 Gyr implying little change in the composition or tectonic affinity of the Earth’s early crust from the Hadean to Mesoarchaean

An oceanic subduction origin for Archaean granitoids revealed by silicon isotopes

Co-auteur étrangerInternational audienceModern oceanic crust is constantly produced at oceanic ridges and recycled back into the mantle at subduction zones via plate tectonics. An outstanding question in geology is whether the Earth started in a non-plate tectonic regime, and if it did, when the transition to the modern regime occurred. This is a complicated question to address because Archaean rocks lack mod-ern equivalents to anchor interpretations. Here, we present a silicon isotopic study of 4.0–2.8-Gyr-old tonalite–trondhjemite–granodiorites, as well as Palaeozoic granites and modern adakites. We show that Archaean granitoids have heavier silicon isotopic compositions than granites and adakites, regardless of melting pressure. This is best explained if Archaean granitoids were formed by melting of subducted basaltic crust enriched in sedimentary silica through interaction with seawater. Before the appearance of silica-forming organisms 0.5–0.6 billion years ago, the oceans were close to silicon saturation, which led to extensive precipitation of cherts on the seafloor. This is in contrast to modern oceans, where silica biomineralization maintains dissolved silicon at low concentration. The unique heavy silicon isotope signature of cherts has been transferred to Archaean granitoids during an oceanic subduction process, which was probably responsible for the formation of felsic rocks on Archaean emerged lands