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Customer expectations are increasing, especially with regard to the individualization of products, in which additive manufacturing is described as a disruptive technology. With a view to using the technology in a series application, extensive knowledge of the starting material, the powder, is necessary. In this article, AlSi10Mg in powder form (grain size range: 15–70 µm), which is used for the selective laser melting process, is analysed on the basis of various investigations. A distinction is made from other researchers, as a total of six powders of the same specification but from different manufacturers were used. An investigation of the relative humidity of the powders in the as-delivered condition was carried out using a moisture meter. It could be shown that the moisture lies between 5% and 15% and that the moisture can be reduced by about half by using dry bags. A qualitative examination with a scanning electron microscopy showed that the morphology and size distribution differ. Not only partially round, but also very misshapen particles and particles with and without adhesions are present. The flowability was determined with a calibrated Hall flowmeter. It was found that a lower proportion of fine particles in the powder lead to a more uniform flowability. In the investigation, a distinction was made between powder in the as-received state and dried powder. The particle size distribution was determined with a laser diffraction method and evaluated according to the Mie theory. To be able to carry out porosity analyses on the basis of micrographs, test cubes with the dimensions (10 × 10 × 10 mm3) were used. The parameters scanning speed (400–600 mm/s), hatch spacing (0.19–0.29 mm), and laser power (220–320 W) were varied. The results vary between 0.12% and 5.46% porosity. To combine the results, a pairwise comparison and a use-value analysis were carried out. Overall, the differences in the powders of the different manufacturers were found to be small, so that a recommendation was made for the most economical powder. [ABSTRACT FROM AUTHOR]

Pleural empyema is rarely seen in the newborn period. Here we report the first case of exclusive and successful conservative management of pleural empyema in an extremely low birth weight infant. Chest drainage or percutaneous aspiration was not feasible. Noninvasive treatment might represent an acceptable option in premature infants. [ABSTRACT FROM AUTHOR]

Background Intraventricular hemorrhage (IVH) is one of the most formidable neurological complications in premature infants. Low grade IVH is often regarded as a low risk factor for long-term neurological impairment. Methods We retrospectively investigated, if there was an association of low IVH grade and adverse neurological outcome in survivors at 20–24 months of corrected age. Results 89 infants, median gestational age 27 + 4, were included in the study. In total 55 children with IVH grade I ( n = 34) or grade II ( n = 21), plus 34 children with IVH grade III ( n = 13) and IVH grad IV ( n = 21) were included. In infants with grade I and II IVH median mental developmental index (MDI) and psychomotor developmental index (PDI) were 90 and 88, respectively. In total 18 children (33%) had a MDI one standard deviation below the mean (< 85, < 1SD). 9 out of these 18 had an IVH grade I. 17 infants (31%) had a PDI < 1 SD. An MDI/PDI < 2SD was only found in 7 (13%)/6 (11%) children, respectively. Regression analysis showed that IVH grade ( p < 0,001) and gestational age ( p = 0,008) were significant independent risk factors for an adverse motoric outcome. Conclusion Our collective revealed that an IVH grade I was not always associated with a good outcome. Interpretation and prediction of long outcome prognosis after IVH grade I or II requires careful consideration as it might be associated with increased disability. [ABSTRACT FROM AUTHOR]

Background: Surfactant application by a thin catheter represented by the term less invasive surfactant administration (LISA) for respiratory distress syndrome in spontaneously breathing preterm infants was developed as an alternative to endotracheal intubation., Methods: We conducted a meta-analysis to assess the effects of LISA when compared to the socalled intubation-surfactant-extubation (INSURE) and the standard endotracheal intubation and mechanical ventilation (MV). The primary outcome was the composite incidence of death or bronchopulmonary dysplasia at a postmenstrual age of 36 weeks. The secondary outcome was the composite incidence of seven other severe adverse events. On 06 October 2021, we searched randomized clinical trials (RCTs) in PubMed, the Cochrane Library, ClinicalTrials.gov, and the ICTRP Registry., Results: We included 18 RCTs. The pooled data on the primary outcome favored LISA when compared to either INSURE (risk ratio 0.67; 95% CI, 0.51 to 0.88) or MV (risk ratio 0.78; 95% CI, 0.61 to 0.99). The pooled data on the second outcome also favored LISA when compared to INSURE (risk ratio 0.75; 95% CI, 0.60 to 0.94) and MV (risk ratio 0.73; 95% CI, 0.55 to 0.96)., Conclusion: The findings showed that surfactant application by non-intubation respiratory support and the use of a thin catheter may decrease the composite risk of death or bronchopulmonary dysplasia. The included data support the view that LISA should be considered the preferred treatment option in eligible infants., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)