Second-Generation central venous catheter in the prevention of bloodstream infection: a systematic review

Cirrhotic Liver of Liver Transplant Recipients Accumulate Silver and Co-Accumulate Copper

Silver-based materials are widely used in clinical medicine. Furthermore, the usage of silver containing materials and devices is widely recommended and clinically approved. The impact on human health of the increasing use of silver nanoparticles in medical devices remains understudied, even though Ag-containing dressings are known to release silver into the bloodstream. In this study, we detected a widespread and sometimes significant silver accumulation both in healthy and sick liver biopsies, levels being statistically higher in patients with various hepatic pathologies. 28 healthy and 44 cirrhotic liver samples were investigated. The median amount of 0.049 ppm Ag in livers was measured in cirrhotic livers while the median was 0.0016 ppm for healthy livers (a more than 30-fold difference). The mean tissue concentrations of essential metals, Fe and Zn in cirrhotic livers did not differ substantially from healthy livers, while Cu was positively correlated with Ag. The serum levels of gamma-glutamyl transpeptidase (GGTP) was also positively correlated with Ag in cirrhotic livers. The increased Ag accumulation in cirrhotic livers could be a side effect of wide application of silver in clinical settings. As recent studies indicated a significant toxicity of silver nanoparticles for human cells, the above observation could be of high importance for the public health.

In vitro activity of antimicrobial-impregnated catheters against biofilms formed by KPC-producing Klebsiella pneumoniae

AIM

To evaluate the activity and effectiveness of impregnated central venous catheters (CVC) against Klebsiella pneumoniae biofilms.

METHODS AND RESULTS

The antimicrobial activity and durability of impregnated-CVCs were evaluated over time and the size of zones of inhibition (ZI) was measured. Biofilm formation was observed by quantitative culture and also by scanning electron microscopy. The catheters impregnated with chlorhexidine/silver sulfadiazine (CHX/SS) reduced bacteria counts by 0·3 log and were most effective (P < 0·01) against Klebsiella pneumoniae biofilms N-acetylcysteine/levofloxacin (NAC/LEV) catheters. It was observed that the catheter impregnated with NAC/LEV had initially the largest average ZI size being statistically significant (P < 0·01). The NAC/LEV combination remained active until day 30, whereas the combination of CHX/SS was completely inactivated from day 15 on.

CONCLUSIONS

The NAC/LEV combination showed greater durability on the catheters, but it was the CHX/SS combination that had the greater initial efficacy in bacterial inhibition. It was also observed that NAC/LEV-impregnated catheters do not prevent the emergence of resistant subpopulations inside the inhibition halos during antimicrobial susceptibility tests.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results highlighted that the in vitro efficacy of antimicrobial-impregnated CVCs is limited by time and that their colonization occurred earlier than expected. Our data also demonstrated that NAC/LEV remained active until day 30 of evaluation and CHX/SS combination was completely inactivated from day 15 on. Our findings suggested that implantable devices should be carefully used by medical community.

Risk Factors of Infection and Role of Antibiotic Prophylaxis in Totally Implantable Venous Access Port Placement: Propensity Score Matching

BACKGROUND

To evaluate risk factors of infection and effectiveness of preprocedural single-dose intravenous prophylactic antibiotic (PABX) during totally implantable venous access port (TIVAP) placement in preventing procedure-related infections.

METHODS

This was a retrospective single-institution multicenter study evaluating short-term (30-day) infection outcomes after TIVAP placement. Correlation between infection rates and clinical factors, including hematologic versus non-hematologic malignancy, inpatient versus outpatient status, single versus double lumen and PABX, was investigated using univariate and multivariable analysis in the overall study population as well as the propensity-score-matched cohort.

RESULTS

Overall, 5967 patients underwent TIVAP placement from 2005 to 2016, of which 3978 (67%) patients received PABX. On propensity score matching, 1952 patients with PABX were matched to the same number of patients without PABX. TIVAP was removed due to infection concern in 48 patients in unmatched and 30 patients in matched population. There was no difference in the rate of infection between those who received PABX and those who did not in both unmatched and matched population (p = 0.5387 and 0.9999). Although infection rate was significantly higher in patients who had TIVAP placement in inpatient setting (p < 0.0001), who received a double-lumen TIVAP (p < 0.0001), or who had hematologic malignancy (p = 0.0004) on univariate analysis, inpatient status was the sole factor associated with higher rate of TIVAP infection on multivariable analysis of both overall (odds ratio 2.31, p < 0.0001) and matched populations (odds ratio 4.36, p = 0.0004).

CONCLUSION

Placement of TIVAP in inpatient setting increases the risk of TIVAP infection. PABX before TIVAP placement does not prevent short-term procedure-related infections.