Indoor Airborne Microbiome and Endotoxin: Meteorological Events and Occupant Characteristics Are Important Determinants.

Airborne bacteria and endotoxin may affect asthma and allergies. However, there is limited understanding of the environmental determinants that influence them. This study investigated the airborne microbiomes in the homes of 1038 participants from five cities in Northern Europe: Aarhus, Bergen, Reykjavik, Tartu, and Uppsala. Airborne dust particles were sampled with electrostatic dust fall collectors (EDCs) from the participants' bedrooms. The dust washed from the EDCs' clothes was used to extract DNA and endotoxin. The DNA extracts were used for quantitative polymerase chain (qPCR) measurement and 16S rRNA gene sequencing, while endotoxin was measured using the kinetic chromogenic limulus amoebocyte lysate (LAL) assay. The results showed that households in Tartu and Aarhus had a higher bacterial load and diversity than those in Bergen and Reykjavik, possibly due to elevated concentrations of outdoor bacterial taxa associated with low precipitation and high wind speeds. Bergen-Tartu had the highest difference (ANOSIM R = 0.203) in ß diversity. Multivariate regression models showed that α diversity indices and bacterial and endotoxin loads were positively associated with the occupants' age, number of occupants, cleaning frequency, presence of dogs, and age of the house. Further studies are needed to understand how meteorological factors influence the indoor bacterial community in light of climate change.

Sustained low catheter related infection (CRI) incidence in an observational follow-up study of 9924 catheters using automated data scripts as quality assurance for central venous catheter (CVC) management.

Background: To maintain a low incidence of Catheter Related Infections (CRI) and Catheter Related Bloodstream Infections (CRBSI), continuous follow-up studies on catheter management are necessary. The aims of the present study were to investigate the incidence of catheter tip colonisation, CRI and CRBSI in the Region, to further explore the feasibility of automatic data collection and to investigate associations between independent variables and CRI. Methods: Data from electronic patient charts on all documented central venous catheter (CVC) insertions from multiple hospitals in southern Sweden, between March 2019 and August 2020, were automatically extracted. Multivariable regression analyses were used to identify associated risk factors. Results: In total, 9924 CVC insertions were included. The prevalence of CRI and CRBSI were 0.7% (n = 74) and 0.02% (n = 20) with incidences of 1.2/1000 catheter days and 0.3/1000 catheter days, respectively. Conclusions: We found a sustained low incidence of CRI and CRBSI in the Region. Catheter tips were less likely to be colonised when the subclavian route was used compared to the internal jugular route and male sex as well as increased number of catheter lumens were associated with both catheter tip colonisation and CRI. By using automated scripts, data extraction was efficient and feasible but also demonstrated that real-time quality assurance should be recommended, since this is superior to current standard.

Blood compatibility of widely used central venous catheters; an experimental study.

An inserted central venous catheter (CVC) is considered foreign material by the inert host defence systems and induce inflammation and thrombus formation. The objective of this study was to evaluate blood compatibility of six commonly used CVCs. Three coated and three uncoated CVC materials were tested in a modified Chandler loop model. Each catheter material circulated in blood from ten different healthy volunteers for 1 h. Blood cell counts and measurements of the inert host defence systems were performed on blood samples from the loop. All the tested catheters demonstrated impact on blood cells, contact coagulation, the complement system, or inflammatory markers, although the impact varied significantly. Of the catheters we evaluated, the most unfavourable blood compatibility profile was found for the polyurethane CVC coated with chlorohexidine and silver sulfadiazine. The greatest variation in blood compatibility between test runs was noted for the silicone dialysis catheter. Poor blood compatibility should be taken seriously but given the experimental design of the current study the clinical significance remains to be evaluated.

Central venous catheter-related complications in hematologic patients: An observational study.

BACKGROUND: The frequency of central venous catheter (CVC)-related complications in hematologic patients has previously been studied but some uncertainty remains. Therefore, this observational cohort study was designed primarily to investigate mechanical and infectious complications related to CVC insertion in hematologic patients and secondarily to identify factors associated with these complications. METHODS: Documented data on CVC insertions in all adult hematologic patients who received a CVC from 2013 to 2019 at a University Hospital in Sweden were retrospectively collected. RESULTS: A total of 589 CVC insertions in 387 patients were included. The prevalence of moderate and severe mechanical complications, predominantly comprising grades 2-4 bleeding, was 11%. Preprocedural coagulopathy, number of needle passes, and arterial puncture were all independently associated with grades 2-4 bleeding. The incidence of suspected catheter-related infections (sCRI) was 3.7/1000 catheter days. Higher body mass index and male gender were independently associated with sCRI. CONCLUSIONS: Patients with hematologic malignancies have a high risk of both grades 2-4 bleeding and sCRI after CVC insertion. This underlines the importance of optimizing the conditions at the insertion and also of daily inspections, evaluation of future needs, and extra precautions to avoid sCRI in these susceptible patients.

Biofilm formation on three different endotracheal tubes: a prospective clinical trial.

BACKGROUND: Biofilm formation on endotracheal tubes (ETTs) is an early and frequent event in mechanically ventilated patients. The biofilm is believed to act as a reservoir for infecting microorganisms and thereby contribute to development and relapses of ventilator-associated pneumonia (VAP). Once a biofilm has formed on an ETT surface, it is difficult to eradicate. This clinical study aimed to compare biofilm formation on three widely used ETTs with different surface properties and to explore factors potentially predictive of biofilm formation. METHODS: We compared the grade of biofilm formation on ETTs made of uncoated polyvinyl chloride (PVC), silicone-coated PVC, and PVC coated with noble metals after > 24 h of mechanical ventilation in critically ill patients. The comparison was based on scanning electron microscopy of ETT surfaces, biofilm grading, surveillance and biofilm cultures, and occurrence of VAP. RESULTS: High-grade (score ≥ 7) biofilm formation on the ETTs was associated with development of VAP (OR 4.17 [95% CI 1.14-15.3], p = 0.031). Compared to uncoated PVC ETTs, the silicone-coated and noble-metal-coated PVC ETTs were independently associated with reduced high-grade biofilm formation (OR 0.18 [95% CI 0.06-0.59], p = 0.005, and OR 0.34 [95% CI 0.13-0.93], p = 0.036, respectively). No significant difference was observed between silicon-coated ETTs and noble-metal-coated ETTs (OR 0.54 [95% CI 0.17-1.65], p = 0.278). In 60% of the oropharyngeal cultures and 58% of the endotracheal cultures collected at intubation, the same microorganism was found in the ETT biofilm at extubation. In patients who developed VAP, the causative microbe remained in the biofilm in 56% of cases, despite appropriate antibiotic therapy. High-grade biofilm formation on ETTs was not predicted by either colonization with common VAP pathogens in surveillance cultures or duration of invasive ventilation. CONCLUSION: High-grade biofilm formation on ETTs was associated with development of VAP. Compared to the uncoated PVC ETTs, the silicone-coated and noble-metal-coated PVC ETTs were independently associated with reduced high-grade biofilm formation. Further research on methods to prevent, monitor, and manage biofilm occurrence is needed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02284438 . Retrospectively registered on 21 October 2014.

Catheter-related infections: A Scandinavian observational study on the impact of a simple hygiene insertion bundle.

BACKGROUND: Catheter-related infections (CRIs) and catheter-related bloodstream infections (CRBSIs) are among the most frequent hospital acquired infections. CRI/CRBSI studies in Scandinavian cohorts are scarce. The primary aim of this study was to investigate the CRI/CRBSI incidence and the association between potential risk factors, including the introduction of a simple hygiene insertion bundle and CRIs at a large university hospital in Sweden. METHODS: We retrospectively included all patients aged 12 and above who received a central venous catheter (CVC) or a central dialysis catheter during a 2-year period, 1 year before and 1 year after the implementation of a simple hygiene insertion bundle. Microbiological data, including catheter tip cultures and blood cultures, were merged with CVC insertion data. RESULTS: A total of 1722 catheter insertions in 1428 patients were included. CRI and CRBSI incidence were 1.86/1000 and 0.62/1000 catheter days, respectively. In a multivariable regression model, the implementation of a simple hygiene insertion bundle was the independent factor most strongly associated with significantly lower CRI-incidence (95% confidence interval [CI] of odds ratio [OR] 0.23-0.92, P = .029). Choosing multiple lumen catheters was associated with increasing CRI-incidence (95% CI of OR 1.11-2.39, P = .013). CONCLUSION: The incidence of catheter-related infections and catheter-related bloodstream infections in this Scandinavian cohort was low. The implementation of a simple hygiene insertion bundle seems to be an effective intervention for reducing catheter-related infections. The use of multiple-lumen catheters is associated with increased risk of catheter-related infections.

[Evaluation of thromboprophylactic therapy at Landspítali - The National University Hospital of Iceland; a cross-sectional study on acute wards]. / Frammistada Landspitala i forvornum gegn blaaedasegasjukdomum; thversnidsrannsokn a bradadeildum.

OBJECTIVE: Venous thromboembolic disease is a serious and often fatal complication following hospital admission. Studies show that thromboprophylactic therapy for this condition is often underutilized. The aim of this study was to evaluate the performance of thromboprophylactic therapy at Landspítali - The University Hospital of Iceland in adult patients admitted to acute wards. METHODS AND MATERIALS: On 2 December 2009 hospital charts of admitted patients on acute wards were reviewed and assessed for appropriate thromboprophylactic treatment according to the 2008 guidelines from The American College of Chest Physicians. The results were compared to those of other countries from the multinational Endorse study from 2008. RESULTS: 251 patient were included of whom 47% were considered at risk for venous thromboembolic disease. Of those 57% received appropriate thromboprophylactic treatment or 78% of surgical and 26% of medical patients. CONCLUSIONS: Adherence to clinical guidelines for thromboprophylactic treatment at surgical wards of Landspítali - The National University Hospital of Iceland was good and well above the average compared to the results of the Endorse study. Performance on the medical wards was on the other hand below average. Our results show that application of thromoboprophylactic treatment at Landspítali could be improved and thereby enhance patient safety.