Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Experimental acrylonitrile butadiene styrene and polyamide evisceration implant: a rabbit clinical and histopathology study

ABSTRACT The purpose of this study was to evaluate acrylonitrile butadiene styrene (ABS) and polyamide implants in rabbits submitted to evisceration at the macroscopic and microstructure level and to assess clinical response and histopathological changes as well. For the experimental study implants of 12mm diameter were prepared by rapid prototyping, weighed and the outer and inner surfaces evaluated macroscopically and by electron microscopy. In addition, a compression test was performed and ultrastructural damage was then determined. After evisceration of the left eyeball, nine New Zealand rabbits received ABS implants and nine others received polyamide implants. The animals were assessed daily for 15 days after surgery and every seven days until the end of the study (90 days). Histopathological evaluation was performed at 15, 45 and 90 days after surgery. The ABS implants weighed approximately 0.44g, while the polyamide ones weighed 0.61g. Scanning electron microscopy demonstrated that the ABS implants had regular-sized, equidistant micropores, while the polyamide ones showed micropores of various sizes. The force required to fracture the ABS implant was 14.39 ±0.60 Mpa, while for the polyamide one, it was 16.80 ±1.05 Mpa. Fifteen days after surgery, we observed centripetal tissue infiltration and scarce inflammatory infiltrate. Implants may be used in the filling of anophthalmic cavities, because they are inert, biocompatible and allow tissue integration

Gadolinium luminescent materials obtained by spray pyrolysis, co-precipitation, and non-hydrolytic sol-gel route: Structure and optical properties

cited By 0International audienceImproving luminescent materials has been the focus of researchers working in the areas of solid-state lasers, scintillators for medical imaging, and phosphors, among others. Lanthanide materials have wide application in optical fibers, amplifiers, and display devices: the inner shell electronic transitions between the 4f-4f energy levels of the lanthanide ions (Ln3+) provide them with excellent luminescent properties. We prepared the inorganic matrixes GdAlO3, Gd2O3, GdCaAl3O7, GdVO4, GdNbO4, and Gd2O2S doped with europium ions (Eu3+) in three different ways: (1) non-hydrolytic sol-gel route, by reacting the precursor metal chlorides in ethanol; (2) spray pyrolysis, using aqueous solution; and (3) co-precipitation synthesis, by reacting the precursor metal nitrates with urea in water, followed by various heat treatments. We characterized the resulting powders by thermal analyses, X-ray diffraction (XRD) analysis, scanning electron microscopy, and Eu3+ photoluminescence. The thermogravimetric curves showed mass loss, attributed to water molecules weakly bound to the oxide surface, solvent molecules, pyrolysis of organic matter remaining from the synthesis, and structural arrangement. The differential thermogravimetric curves evidenced exothermic peaks at different temperatures, associated with the structural rearrangement of the matrixes. The samples were thermally treated; the XRD patterns presented peaks ascribed to the crystalline phases of GdAlO3, GdCaAl3O7, Gd2O3, Gd2O2S, GdVO4, and GdNbO4, depending on the matrix. These results confirmed that the methodologies used to synthesize the materials were efficient. The morphological study revealed particles with different sizes and shapes: spray pyrolysis, co-precipitation synthesis, and the non-hydrolytic sol-gel methodology furnished particles measuring around 500 nm, spherical particles of around 100 nm, and irregular particles with less than 100 nm, respectively. For all the matrixes, the excitation spectra of Eu3+ displayed a broad band at shorter wavelength, assigned to the charge transfer between the ligand and the metal (O2-→ Eu3-or S2-→ Eu3-) and to the f-f transitions of the Eu3-excited state. Some spectra presented a band relative to the excited state of the Gd3+ ion, indicating Gd3+ → Eu3-energy transfer. The emission spectra of Eu3+, excited at different wavelengths, exhibited narrow lines between 500 and 750 nm, relative to the typical transition from the excited level to manifold level (5D0 → 7F2, with J = 0, 1, 2, 3, and 4). The more intense band of the matrixes corresponded to the hypersensitive transition 5D0 → 7F2, with dipole-electric character, detected with maximum at approximately 615 nm. The synthetic processes used here furnished gadolinium matrixes with excellent luminescent red emission; in some matrixes, Gd3+ efficiently transferred energy to Eu3+. Therefore, these materials have promising technological applications in luminescent devices