Clinical Impacts and Risk Factors for Central Line-Associated Bloodstream Infection: A Systematic Review.

Background A central line-associated bloodstream infection (CLABSI) is defined as a primary bloodstream infection (BSI) in a patient that had a central line within the 48-hour period before the development of the BSI and is not bloodstream-related to an infection at another site. CLABSI is a common healthcare-associated infection and a significant cause of morbidity and mortality. Methods This systematic review included studies published within the past 13 years that examined risk factors and clinical impact variables associated with CLABSI, using the Centers for Disease Control (CDC)/National Healthcare Safety Network (NHSN) criteria for defining catheter-associated infection, and included participants of all ages. The terms "CLABSI," "central line-associated bloodstream infection," "risk factors," "predictors," "morbidity," "mortality," "healthcare costs," and "length of hospital stay" were used to find relevant publications on PubMed/Medline, Google Scholar, and Science Direct. The quality assessment of the included publications utilized the modified Newcastle-Ottawa scale (NOS) for observational studies. Results After the full-text screening, we identified 15 articles that met our inclusion and exclusion criteria. The majority of these studies were of good quality and had a low risk of bias based on our bias assessment. The studies included a total of 32,198 participants and covered a time period from 2010 to 2023. The mean age of the male patients included in the studies ranged from 0.1 months to 69.1 years. All of the included studies were either observational cohort studies, cross sectional studies, case-control studies, or case reports. The major study parameters/outcomes extracted were risk factors, CLABSI-associated mortality, hospital cost, length of hospital stay, and catheter days. With respect to predisposing factors, multilumen access catheters were identified as risk factors in three studies, use of more than one central venous catheter per case in four studies, hematologic malignancy in three studies, catheterization duration in four studies, surgical complexity in four studies, length of ICU stays in three studies, and parenteral nutrition in two studies. Conclusion The decision to place a venous device should be carefully considered by evaluating individual risk factors for the development of CLABSI. This is important due to the potential for severe clinical consequences and significant healthcare expenses associated with this complication.

Combined Computational and Experimental Investigation on the Nature of Hydrated Iodoplumbate Complexes: Insights into the Dual Role of Water in Perovskite Precursor Solutions.

Water is generally considered an enemy of metal halide perovskites, being responsible for their rapid degradation and, consequently, undermining the long-term stability of perovskite-based solar cells. However, beneficial effects of liquid water have been surprisingly observed, and synthetic routes including water treatments have shown to improve the quality of perovskite films. This suggests that the interactions of water with perovskites and their precursors are far from being completely understood, as water appears to play a puzzling dual role in perovskite precursor solutions. In this context, studying the basic interactions between perovskite precursors in the aqueous environment can provide a deeper comprehension of this conundrum. In this context, it is fundamental to understand how water impacts the chemistry of iodoplumbate perovskite precursor species, PbIx2-x. Here, we investigate the chemistry of these complexes using a combined experimental and theoretical strategy to unveil their peculiar structural and optical properties and eventually to assign the species present in the solution. Our study indicates that iodide-rich iodoplumbates, which are generally key to the formation of lead halide perovskites, are not easily formed in aqueous solutions because of the competition between iodide and solvent molecules in coordinating Pb2+ ions, explaining the difficulty of depositing lead iodide perovskites from aqueous solutions. We postulate that the beneficial effect of water when used as an additive is then motivated by its behavior being similar to high coordinative polar aprotic solvents usually employed as additives in one-step perovskite depositions.

Tin versus Lead Redox Chemistry Modulates Charge Trapping and Self-Doping in Tin/Lead Iodide Perovskites.

Tin halide perovskites make up the only lead-free material class endowed with optoelectronic properties comparable to those of lead iodide perovskites. Despite significant progress, the device efficiency and stability of tin halide perovskites are still limited by two potentially related phenomena, i.e., self-p-doping and tin oxidation. Both processes are likely related to defects; thus, understanding tin halide defect chemistry is a key step toward exploitation of this class of materials. We investigate the MASnI3 perovskite defect chemistry, as a prototype of the entire materials class, using state-of-the-art density functional theory simulations. We show that the inherently low ionization potential of MASnI3 is solely responsible of the high stability of tin vacancy and interstitial iodine defects, which are in turn at the origin of the material p-doping. Tin vacancies create a locally iodine-rich environment that could promote Sn(II) → Sn(IV) oxidation. The higher band edge energies of MASnI3 compared to those of MAPbI3 lead to the emergence of deep electron traps associated with undercoordinated tin defects (e.g., interstitial tin) and the suppression of deep transitions associated with undercoordinated iodine defects that are typical of MAPbI3. Thus, while lead iodide perovskites are dominated by iodine chemistry, tin chemistry dominates tin iodide perovskite defect chemistry. Mixed tin/lead perovskites exhibit an intermediate behavior and are predicted to be potentially free of deep traps. Compositional alloying with different metals is finally explored as a strategy for mitigating defect formation and self-p-doping in tin iodide perovskites.