Cathasept Line Lock and Microbial Colonization of Tunneled Hemodialysis Catheters: A Multicenter Randomized Controlled Trial

Association between 4%-tetrasodium EDTA and sepsis in neonatal piglets: A retrospective cohort study

BACKGROUND

Central line-associated bloodstream infections are a major concern for children with intestinal failure and in animal research using parenteral nutrition (PN). In neonatal piglets receiving PN, we compared sepsis, line occlusions, line replacements, mortality, and costs with and without the use of a 4%-tetrasodium ethylenediaminetetraacetic acid (T-EDTA) locking solution.

METHODS

We performed a retrospective review of piglets with a central venous jugular catheter enrolled in 14-day exclusive PN (TPN) trials or in 7-day short bowel syndrome (SBS) trials, before and after initiation of T-EDTA. Lines were locked with a 1-ml solution for 2 h daily (T-EDTATPN, n = 17; T-EDTASBS, n = 48) and compared with our prior standard of care using 1.5-ml heparin flushes twice daily (CONTPN, n = 34; CONSBS, n = 48). Line patency and signs of sepsis were checked twice daily. Jugular catheters were replaced for occlusions whenever possible. Humane end points were used for sepsis not responding to antibiotic treatment or unresolved catheter occlusions.

RESULTS

Compared with CON, sepsis was reduced using T-EDTA, significantly for TPN (P = 0.006) and with a trend for SBS piglets (P = 0.059). Line occlusions necessitating line changes were reduced 15% in TPN studies (P = 0.16), and no line occlusions occurred for T-EDTA SBS piglets.

CONCLUSION

In our neonatal piglet research, use of T-EDTA locking solution decreased sepsis and, although not statistically significant, reduced occlusions requiring line replacements. Given the expense of animal research, adding a locking solution must be cost-effective, and we were able to show that T-EDTA significantly reduced total research costs and improved animal welfare.

Cost-utility analysis of 4% tetrasodium ethylenediaminetetraacetic acid, taurolidine, and heparin lock to prevent central line-associated bloodstream infections in children with intestinal failure

BACKGROUND

Central line-associated bloodstream infections (CLABSI) are a serious complication in children with intestinal failure. This study assessed the incremental costs of 4% tetrasodium ethylenediaminetetraacetic acid (EDTA) compared with taurolidine lock and heparin lock per quality-adjusted life-year (QALY) gained in children with intestinal failure from the healthcare payer and societal perspective.

METHODS

A Markov cohort model of a 1-year-old child with intestinal failure was simulated until the age of 17 years (time horizon), with a cycle length of 1 month. The health outcome measure was QALYs, with results expressed in terms of incremental costs and QALYs. Model parameters were obtained from published literature and institutional data. Deterministic, probabilistic, and scenario sensitivity analyses were performed.

RESULTS

4% Tetrasodium EDTA was dominant (more effective and less expensive) compared with taurolidine and heparin, yielding an additional 0.17 QALYs with savings of CAD$88,277 compared with heparin, and an additional 0.06 QALYs with savings of CAD$52,120 compared with taurolidine lock from the healthcare payer perspective. From the societal perspective, 4% tetrasodium EDTA resulted in savings of CAD$90,696 compared with heparin and savings of CAD$36,973 compared with taurolidine lock.

CONCLUSIONS

This model-based analysis indicates that 4% tetrasodium EDTA can be considered the optimal strategy compared with taurolidine and heparin in terms of cost-effectiveness. The decision uncertainty can be reduced by conducting further research on the model input parameters. An expected value of perfect information analysis can identify what model input parameters would be most valuable to focus on.

A Systematic Review of the Impact of Antibiotic and Antimicrobial Catheter Locks on Catheter-Related Infections in Adult Patients Receiving Hemodialysis

Central venous catheter (CVC)-based hemodialysis is a major contributor to bacteremia in immunocompromised hosts. Heparin-locking CVCs is a frequent therapeutic procedure. However, it has not been shown to reduce catheter-related bloodstream infections (CRBSIs). For this systematic review, we searched PubMed, PubMed Central, ResearchGate, Science Direct, and Multidisciplinary Digital Publishing Institute (MDPI) for multiple articles published between January 2018 and January 2023 to determine how antimicrobial locking solutions affect CRBSIs, which could ultimately lower the risk of morbidity, mortality, and hospitalization costs. Antilocking products, catheter-related bacteremia, central-line associated bloodstream infections, tunneled dialysis catheter, hemodialysis, antibiotic, and antimicrobial catheter locks, and the Medical Subject Heading (MeSH) method for PubMed were used as the main keywords for searching publications. A pool of 13 studies with 46,139 individuals showed that the therapy group had a lower incidence of CRBSIs than the heparin-treated control group. Furthermore, it was discovered that bacteria were resistant to gentamicin, and the use of antibiotics had no discernible impact on catheter malfunction. In conclusion, the most effective locking solution to date is an antilocking solution made up of an antibiotic or antimicrobial agent combined with low-dose heparin (500-2,500 U/mL).

Reevaluation of lock solutions for Central venous catheters in hemodialysis: a narrative review

BACKGROUND

A significant proportion of incident and prevalent hemodialysis patients have central venous catheters for vascular access. No consensus is available on the prevention of catheter dysfunction or catheter-related bloodstream infections in patients undergoing hemodialysis by means of catheter lock solutions.

METHOD

We reviewed the effects of single and combined anticoagulants with antibacterial catheter lock solutions or other antimicrobials for the prevention of thrombosis or infections in hemodialysis patients. Relative risks with 95% confidence intervals for trials of the same type of catheter locking solution were pooled.

SOURCES OF INFORMATION

We included original research articles in English from PubMed, EMBASE, SpringerLink, Elsevier and Ovid using the search terms 'hemodialysis,' 'central venous catheter,' 'locking solution,' 'UFH,' 'low molecular weight heparin,' 'EDTA,' 'citrate,' 'rt-PA,' 'urokinase,' 'gentamicin,' 'vancomycin', 'taurolidine,' 'sodium bicarbonate,' 'hypertonic saline' and 'ethanol' and 'catheter'.

FINDINGS

Low-dose heparin lock solution (< 5000 U/ml) can efficiently achieve anticoagulation and will not increase the risk of bleeding. Low-concentration citrate (< 5%) combined with rt-PA can effectively prevent catheter infection and dysfunction. Catheter-related infections may be minimized by choosing the appropriate antibiotic and dose.

LIMITATIONS

There is a lack of follow-up validation data for LMWH, EDTA, taurolidine, sodium bicarbonate, ethanol, and other lock solutions.

IMPLICATIONS

Since catheterization is common in hemodialysis units, studies on long-term treatment and preventative strategies for catheter dysfunction and catheter-related infection are warranted.

Central venous access device locking practices in the adult critical care setting: a single-centre, observational study establishing duration of locking per catheter lumen

PURPOSE

Central line complications remain a problem in critical care patient populations. Various interventions to prevent or treat complications, such as central line-associated bloodstream infection and occlusion, have been the focus of recent research. Although alternative catheter locking solutions have been shown to be effective in other patient populations, their applicability to the critical care setting remains unclear. Due to the high acuity of critical care patients, it is uncertain whether their central lines remain locked for a duration long enough for alternative locking solutions to provide any effect.

METHODS

This single-centre, prospective, observational study aimed to gather information about the length of time central line lumens remain in a locked state in the average critical care patient. Baseline rates of various central line complications were also tracked.

RESULTS

Results of this study indicate that the majority of central lines will have at least one lumen locked for an average of 36.6% of their time in situ.

CONCLUSIONS

It is anticipated that this length of time provides enough exposure for alternative locking solutions to potentially make a difference in central line complications in this patient population. Results of this study can be used for planning future multi-centre, randomized controlled trials investigating the efficacy of novel central line locking solutions to prevent central line complications in critically ill patients.

Control of Line Complications with KiteLock (CLiCK) in the critical care unit: study protocol for a multi-center, cluster-randomized, double-blinded, crossover trial investigating the effect of a novel locking fluid on central line complications in the critical care population

Background

Insertion of a central venous access device (CVAD) allows clinicians to easily access the circulation of a patient to administer life-saving interventions. Due to their invasive nature, CVADs are prone to complications such as bacterial biofilm production and colonization, catheter-related bloodstream infection, occlusion, and catheter-related venous thrombosis. A CVAD is among the most common interventions for patients in the intensive care unit (ICU), exposing this vulnerable population to the risk of nosocomial infection and catheter occlusion. The current standard of care involves the use of normal saline as a catheter locking solution for central venous catheters (CVCs) and peripherally inserted central catheter (PICC) lines, and a citrate lock for hemodialysis catheters. Saline offers little prophylactic measures against catheter complications. Four percent of tetrasodium ethylenediaminetetraacetic acid (EDTA) fluid (marketed as KiteLock Sterile Locking Solution™) is non-antibiotic, possesses antimicrobial, anti-biofilm, and anti-coagulant properties, and is approved by Health Canada as a catheter locking solution. As such, it may be a superior CVAD locking solution than the present standard of care lock in the ICU patient population.

Methods

Our team proposes to fill this knowledge gap by performing a multi-center, cluster-randomized, crossover trial evaluating the impact of 4% tetrasodium EDTA on a primary composite outcome of the incidence rate of central line-associated bloodstream infection (CLABSI), catheter occlusion leading to removal, and use of alteplase to resolve catheter occlusion compared to the standard of care. The study will be performed at five critical care units.

Discussion

If successful, the results of this study can serve as evidence for a shift of standard of care practices to include EDTA locking fluid in routine CVAD locking procedures. Completion of this study has the potential to improve CVAD standard of care to become safer for patients, as well as provides an opportunity to decrease strain on healthcare budgets related to treating preventable CVAD complications. Success and subsequent implementation of this intervention in the ICU may also be extrapolated to other patient populations with heavy CVAD use including hemodialysis, oncology, parenteral nutrition, and pediatric patient populations. On a global scale, eradicating biofilm produced by antibiotic-resistant bacteria may serve to lessen the threat of “superbugs” and contribute to international initiatives supporting the termination of antibiotic overuse.

Trial registration

ClinicalTrials.gov NCT04548713, registered on September 9th, 2020. 

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06671-5.

Management of Central Venous Access in Children With Intestinal Failure: A Position Paper From the NASPGHAN Intestinal Rehabilitation Special Interest Group

ABSTRACT

Intestinal failure requires the placement and maintenance of a long-term central venous catheter for the provision of fluids and/or nutrients. Complications associated with this access contribute to significant morbidity and mortality, while the loss of access is an increasingly common reason for intestinal transplant referral. As more emphasis has been placed on the prevention of central line-associated bloodstream infections and new technologies have developed, care for central lines has improved; however, because care has evolved independently in local centers, care of central venous access varies significantly in this vulnerable population. The present position paper from the Intestinal Failure Special Interest Group of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) reviews current evidence and provides recommendations for central line management in children with intestinal failure.

Surface modification strategies for hemodialysis catheters to prevent catheter-related infections: A review

Insertion of a central venous catheter is one of the most common invasive procedures applied in hemodialysis therapy for end-stage renal disease. The most important complication of a central venous catheter is catheter-related infections that increase hospitalization and duration of intensive care unit stay, cost of treatment, mortality, and morbidity rates. Pathogenic microorganisms, such as, bacteria and fungi, enter the body from the catheter insertion site and the surface of the catheter can become colonized. The exopolysaccharide-based biofilms from bacterial colonies on the surface are the main challenge in the treatment of infections. Catheter lock solutions and systemic antibiotic treatment, which are commonly used in the treatment of hemodialysis catheter-related infections, are insufficient to prevent and terminate the infections and eventually the catheter needs to be replaced. The inadequacy of these approaches in termination and prevention of infection revealed the necessity of coating of hemodialysis catheters with bactericidal and/or antiadhesive agents. Silver compounds and nanoparticles, anticoagulants (e.g., heparin), antibiotics (e.g., gentamicin and chlorhexidine) are some of the agents used for this purpose. The effectiveness of few commercial hemodialysis catheters that were coated with antibacterial agents has been tested in clinical trials against catheter-related infections of pathogenic bacteria, such as Staphylococcus aureus and Staphylococcus epidermidis with promising results. Novel biomedical materials and engineering techniques, such as, surface micro/nano patterning and the conjugation of antimicrobial peptides, enzymes, metallic cations, and hydrophilic polymers (e.g., poly [ethylene glycol]) on the surface, has been suggested recently.

Efficacy of 4% tetrasodium ethylenediaminetetraacetic acid (T-EDTA) catheter lock solution in home parenteral nutrition patients: A quality improvement evaluation

Introduction:

A functioning and reliable central venous access device is fundamental for home parenteral nutrition patients to administer essential nutrition. Complications of central venous access devices including occlusion, microbial colonization, and biofilm formation are problematic and sometimes life-threatening. A novel lock solution, 4% tetrasodium ethylenediaminetetraacetic acid, has properties that may reduce such complications.

Purpose:

The aim of this study was to determine the safety, efficacy, and cost implications of implementing 4% tetrasodium ethylenediaminetetraacetic acid to prevent catheter-related complications in home parenteral nutrition patients.

Methods:

A pre- and post-intervention study was carried over 36 months (12 months pre; 24 months post) by the British Columbia Home Parenteral Nutrition Program in Vancouver, Canada, where 4% tetrasodium ethylenediaminetetraacetic acid was implemented for patients at high risk for central venous access device occlusion and catheter-related infection. Patients were included in the study if they had previous central venous access device complications. The outcomes evaluated were central line-associated bloodstream infection, catheter occlusion requiring thrombolytic treatment, and catheter replacements.

Results:

In total, 22 out of 105 patients met the inclusion criteria. Two patients were excluded from analyses due to non-adherence and concomitant use of other lock solutions. Post intervention, 20 home parenteral nutrition patients experienced significant reduction in the central line-associated bloodstream infection rate (pre = 1.918/1000 catheter days; post = 0.563/1000 catheter days; p = 0.04) There were no occlusion events reported post intervention.

Conclusion:

For home parenteral nutrition patients, 4% tetrasodium ethylenediaminetetraacetic acid lock solution effectively reduces the risk of central venous access device complications including occlusions and catheter-related infections.

Placement of ureteral stents in three rabbits for the treatment of obstructive ureterolithiasis

Management of ureteral obstruction with stenting is often associated with a lower rate of complications than ureterotomy in domestic carnivores, but this treatment has not been previously evaluated in rabbits. Three rabbits (7, 6 and 10 years old) were diagnosed with unilateral obstructive ureterolithiasis associated with hydronephrosis and hydroureter on abdominal ultrasound. Decreased overall renal function was confirmed in all three cases. Ureteral stents were placed retrogradely via cystotomy without complication in two cases and anterogradely via nephrostomy in the third case. Survival after stent placement was 30, 3 and 8 months, with encrustation of the stent and re-obstruction occurring 18, 1 and 6 months after stent placement in successive cases. Ureteral stenting can be considered for short-term management of ureterolithiasis in rabbits to improve renal function and maintain quality of life. Ultrasound or radiographic monitoring is recommended to detect encrustation of the stent. Studies comparing ureteral stenting to ureterotomy in rabbits are needed to determine the effectiveness of these techniques.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

Comparative efficacy and safety of lock solutions for the prevention of catheter-related complications including infectious and bleeding events in adult haemodialysis patients: a systematic review and network meta-analysis

BACKGROUND

Central venous catheters are used extensively as temporary or permanent vascular access for haemodialysis patients. Catheter-related bloodstream infections are the main complication of central venous catheters and increase morbidity and mortality in haemodialysis patients.

OBJECTIVES

The aim was to assess the most appropriate lock solution for central venous catheters to prevent catheter-related bloodstream infections and other complications.

DATA SOURCES

Medline, Embase and the Cochrane Central Register of Controlled Trials from the date of their inception to August 2018 were used as data sources. The reference lists of eligible studies and relevant reviews were also checked.

STUDY ELIGIBILITY CRITERIA AND PARTICIPANTS

Randomized controlled trials (RCTs) comparing different lock solutions for the prevention of central venous catheter-related infectious and bleeding complications for adult dialysis patients were included.

INTERVENTIONS

Interventions were lock solutions for haemodialysis catheters.

METHODS

The primary outcomes were catheter-related bloodstream infections and bleeding events. The secondary outcomes were catheter malfunction, exit-site infection, and all-cause mortality. We estimated summary risk ratios (RRs) using pairwise and network meta-analysis. We assessed the risk of bias of individual studies with the Cochrane risk of bias tool.

RESULTS

Forty-nine trials (7020 patients) were included for this study. Compared with heparin 5000 U/mL, antibiotic locks (antibiotics with trisodium citrate (TSC), ethylenediamine tetraacetic acid (EDTA), heparin 5000 U/mL, low-dose heparin or urokinase) and ethanol locks were more effective in preventing catheter-related bloodstream infections. Antimicrobial agents plus low-dose heparin (500-2500 U/mL), TSC and low-dose heparin locks had lower risk of bleeding events than heparin 5000 U/mL. None of the lock solutions reduced rates of catheter malfunction and all-cause mortality compared with heparin 5000 U/mL. In summary, antibiotics plus low-dose heparin was ranked as the best lock solution. The overall results were not materially changed in sensitivity analyses.

CONCLUSIONS

Taking into account both efficacy and safety, antibiotics plus low-dose heparin (500-2500 U/mL) may be the preferred lock solution.

Therapeutic use of tetrasodium ethylenediaminetetraacetic acid solution for treatment of subcutaneous ureteral bypass device mineralization in cats

Background

Subcutaneous ureteral bypass (SUB) device placement is an increasingly popular treatment option for decompression of ureteral obstruction in cats. Mineralization occlusion of the device occurs in a minority of cases but is the most common complication.

Objective

To evaluate a 2% tetrasodium ethylenediaminetetraacetic acid (tEDTA) solution for treatment of mineralization occlusion in cats with SUBs.

Animals

Six client‐owned cats (8 obstructed devices).

Methods

Case series. Each cat was found to have device occlusion based on a combination of ultrasound examination, SUB irrigation, and failure to identify another cause of device obstruction. Each SUB was drained, irrigated using sterile saline, and infused with 1‐2 mL of 2% tEDTA solution. Success was defined as normalization of flow during subsequent ultrasound visualization while irrigating. The volume and frequency of tEDTA instillations, time to achieve device patency, follow‐up biochemical and ultrasound findings, and future reobstruction events were recorded.

Results

Resolution of mineralization was documented in all 8 SUBs. Reobstruction events occurred in 2 cats, all of which resolved after additional tEDTA infusions, but 1 cat ultimately required device exchange at 356 days from the first tEDTA infusion. In 1 cat, a single infusion was prematurely discontinued because of persistent pelvic dilatation after 1.25 mL of tEDTA had been instilled. No complications were observed.

Conclusions and Clinical Importance

Tetrasodium EDTA infusions can be safely considered as a treatment option for mineralized SUB devices in cats. This solution was easily infused, well tolerated, and avoided the need for SUB device exchange in the majority of cats in which it was used.

Advances in the prevention and management of central-line-associated bloodstream infections: The role of chelator-based catheter locks

The proper functioning of central lines is imperative for the management of patients with cancer or on hemodialysis. However, these lifelines can become infected and can malfunction.Chelators such as citrate and EDTA have been widely studied alone or in combination with other antimicrobial agents in catheter lock solutions to prevent catheter-related bloodstream infections and to maintain catheter patency. Given their anticoagulation, antiplatelet aggregation, antibiofilm, antimicrobial activity, safety profile, as well as their low cost, chelators have long been considered alternatives to heparin and a vital component of catheter lock solutions. In this review, we present a detailed summary of the properties of chelators and in vitro and in vivo studies of chelator-containing lock solutions.

Should you pick the PICC? Prolonged use of peripherally inserted central venous catheters in children with intestinal failure

PURPOSE

Prolonged central vascular access is a source of significant morbidity in children with intestinal failure (IF). In an effort to decrease morbidity, our multidisciplinary IF team has primarily used peripherally inserted central catheters (PICCs) for these patients. We compared outcomes of PICCs to Broviacs®.

METHODS

A review of children with IF (2006-2018) at an academic children's hospital was conducted.

INCLUSION CRITERIA

total parenteral nutrition duration >42 days or small bowel length < 25% of total for gestational age. Complications/1000 catheter days were extracted, and a Poisson model was used to compare complications between PICCs and Broviacs®.

RESULTS

Thirty-seven patients with IF were included, accounting for 19,452 catheter days. There were 209 PICCs (1.2-4F) and 39 Broviacs® (2.7-7F). The median duration of overall PICC access/patient was 166 days (range: 35 days-8 years). Incidences of central line associated blood stream infection and venous thrombosis were 3.95 and 0.55 per 1000 catheter days, respectively. There were no significant differences in complication rates per line per catheter day between PICCs and Broviacs® on multivariate analysis. Broviacs® showed a trend towards increased of catheter-related hospital admissions when compared to PICCs.

CONCLUSIONS

PICCs in children with intestinal failure have similar complication rates to Broviacs® but may reduce catheter-related hospital admissions. Use of tunneled PICCs and increasing experience with this vascular access method may allow it to realize its potential advantages.

LEVEL OF EVIDENCE

Retrospective study, level III.

Re-Evaluating the Protective Effect of Hemodialysis Catheter Locking Solutions in Hemodialysis Patients

Catheter-related bloodstream infections (CRBSIs) and exit-site infections (ESIs) are common complications associated with the use of central venous catheters for hemodialysis. The aim of this study was to analyze the impact of routine locking solutions on the incidence of CRBSI and ESI, in preserving catheter function, and on the rate of all-cause mortality in patients undergoing hemodialysis. We selected publications (from inception until July 2018) with studies comparing locking solutions for hemodialysis catheters used in patients undergoing hemodialysis. A total of 21 eligible studies were included, with a total of 4832 patients and 318,769 days of catheter use. The incidence of CRBSI and ESI was significantly lower in the treated group (citrate-based regimen) than in the controls (heparin-based regimen). No significant difference in preserving catheter function and all-cause mortality was found between the two groups. Our findings demonstrated that routine locking solutions for hemodialysis catheters effectively reduce the incidence of CRBSIs and ESIs, but our findings failed to show a benefit for preserving catheter function and mortality rates. Therefore, further studies are urgently needed to conclusively evaluate the impact of routine locking solutions on preserving catheter function and improving the rates of all-cause mortality.

Tetrasodium EDTA Is Effective at Eradicating Biofilms Formed by Clinically Relevant Microorganisms from Patients' Central Venous Catheters

The colonization of catheters by microorganisms often precludes their long-term use, which can be a problem for human patients that have few body sites available for new catheters. The colonizing organisms often form biofilms, and increasingly these organisms are resistant to multiple antibiotics, making them difficult to treat. In this article, we have taken microorganisms that are associated with biofilm formation in catheters from two Canadian hospitals and tested them with tetrasodium EDTA, a new antimicrobial catheter lock solution. Tetrasodium EDTA was effective at eliminating Gram-positive, Gram-negative, and fungal species and represents a promising alternative to antibiotic treatment with less chance of the organisms developing resistance. We expect that our results will be of interest to researchers and clinicians and will lead to improved patient care.

Central venous access devices (CVADs) are an essential component of modern health care. However, their prolonged use commonly results in microbial colonization, which carries the potential risk of hospital-acquired bloodstream infections. These infections complicate the treatment of already sick individuals and cost the existing health care systems around the world millions of dollars. The microbes that colonize CVADs typically form multicellular biofilms that are difficult to dislodge and are resistant to antimicrobial treatments. Clinicians are searching for better ways to extend the working life span of implanted CVADs, by preventing colonization and reducing the risk of bloodstream infections. In this study, we analyzed 210 bacterial and fungal isolates from colonized CVADs or human bloodstream infections from two hospitals geographically separated in the east and west of Canada and screened the isolates for biofilm formation in vitro. Twenty isolates, representing 12 common, biofilm-forming species, were exposed to 4% tetrasodium EDTA, an antimicrobial lock solution that was recently approved in Canada for use as a medical device. The EDTA solution was effective at eradicating surface-attached biofilms from each microbial species, indicating that it could likely be used to prevent biofilm growth within CVADs and to eliminate established biofilms. This new lock solution fits with antibiotic stewardship programs worldwide by sparing the use of important antibiotic agents, targeting prevention rather than the expensive treatment of hospital-acquired infections.

IMPORTANCE The colonization of catheters by microorganisms often precludes their long-term use, which can be a problem for human patients that have few body sites available for new catheters. The colonizing organisms often form biofilms, and increasingly these organisms are resistant to multiple antibiotics, making them difficult to treat. In this article, we have taken microorganisms that are associated with biofilm formation in catheters from two Canadian hospitals and tested them with tetrasodium EDTA, a new antimicrobial catheter lock solution. Tetrasodium EDTA was effective at eliminating Gram-positive, Gram-negative, and fungal species and represents a promising alternative to antibiotic treatment with less chance of the organisms developing resistance. We expect that our results will be of interest to researchers and clinicians and will lead to improved patient care.

Dialysis catheter management practices in Australia and New Zealand

AIM

Dialysis catheter-associated infections (CAI) are a serious and costly burden on patients and the health-care system. Many approaches to minimizing catheter use and infection prophylaxis are available and the practice patterns in Australia and New Zealand are not known. We aimed to describe dialysis catheter management practices in dialysis units in Australia and New Zealand.

METHODS

Online survey comprising 52 questions, completed by representatives from dialysis units from both countries.

RESULTS

Of 64 contacted units, 48 (75%) responded (Australia 43, New Zealand 5), representing 79% of the dialysis population in both countries. Nephrologists (including trainees) inserted non-tunnelled catheters at 60% and tunnelled catheters at 31% of units. Prophylactic antibiotics were given with catheter insertion at 21% of units. Heparin was the most common locking solution for both non-tunnelled (77%) and tunnelled catheters (69%), with antimicrobial locks being predominant only in New Zealand (80%). Eight different combinations of exit site dressing were in use, with an antibiotic patch being most common (35%). All units in New Zealand and 84% of those in Australia undertook CAI surveillance. However, only 51% of those units were able to provide a figure for their most recent rate of catheter-associated bacteraemia per 1000 catheter days.

CONCLUSION

There is wide variation in current dialysis catheter management practice and CAI surveillance is suboptimal. Increased attention to the scope and quality of CAI surveillance is warranted and further evidence to guide infection prevention is required.

Non-Antibiotic Antimicrobial Catheter Lock Solutions in Patients on Home Parenteral Nutrition

Patients on home parenteral nutrition (HPN) are dependent on central venous access for long-term sustenance, and catheter-related bloodstream infections (CRBSIs) are a major cause of morbidity and mortality in this patient population. As such, there is much interest in finding new methods for preventing CRBSIs in patients on HPN. As it is thought that these infections are preceded by microbial colonization of the catheter, one approach is to use antimicrobial catheter lock solutions. Although antibiotic catheter lock solutions have been present for decades, their use has been mostly limited to the treatment of CRBSIs due to concern for promoting microbial resistance. Recently, however, with the advent of non-antibiotic antimicrobial catheter lock solutions, this approach is gaining popularity as a promising method to decrease rates of CRBSI in HPN patients.

Antimicrobial lock solutions for preventing catheter-related infections in haemodialysis

BACKGROUND

Patients undergoing haemodialysis (HD) through a central venous catheter (CVC) are exposed to several risks, being a catheter-related infection (CRI) and a CVC lumen thrombosis among the most serious. Standard of care regarding CVCs includes their sealing with heparin lock solutions to prevent catheter lumen thrombosis. Other lock solutions to prevent CRI, such as antimicrobial lock solutions, have proven useful with antibiotics solutions, but not as yet for non-antibiotic antimicrobial solutions. Furthermore, it is uncertain if these solutions have a negative effect on thrombosis incidence.

OBJECTIVES

To assess the efficacy and safety of antimicrobial (antibiotic, non-antibiotic, or both) catheter lock solutions for preventing CRI in participants undergoing HD with a CVC.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register up to 18 December 2017 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised or quasi-randomised control trials (RCTs) comparing antimicrobial (antibiotic and non-antibiotic) lock solutions to standard lock solutions, in participants using a CVC for HD, without language restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility, and two additional authors assessed for risk of bias and extracted data. We expressed results as rate ratios (RR) per 1000 catheter-days or 1000 dialysis sessions with 95% confidence intervals (CI). Statistical analyses were performed using the random-effects model.

MAIN RESULTS

Thirty-nine studies, enrolling 4216 participants, were included in this review, however only 30 studies, involving 3392 participants, contained enough data to be meta-analysed. Risk of bias was low or unclear for most domains in the majority of the included studies.Studies compared antimicrobial lock solutions (antibiotic and non-antibiotic) to standard sealing solutions (usually heparin) of the CVC for HD. Fifteen studies used antibiotic lock solutions, 21 used non-antibiotic antimicrobial lock solutions, and 4 used both (antibiotic and non-antibiotic) lock solutions. Studies reported the incidence of CRI, catheter thrombosis, or both.Antimicrobial lock solutions probably reduces CRI per 1000 catheter-days (27 studies: RR 0.38, 95% CI 0.27 to 0.53; I² = 54%; low certainty evidence), however antimicrobial lock solutions probably makes little or no difference to the risk of thrombosis per 1000 catheter days (14 studies: RR 0.79, 95% CI 0.52 to 1.22; I² = 83%; very low certainty evidence). Subgroup analysis of antibiotic and the combination of both lock solutions showed that both probably reduced CRI per 1000 catheter-days (13 studies: RR 0.30, 95% CI: 0.22 to 0.42; I² = 47%) and risk of thrombosis per 1000 catheter-days (4 studies: RR 0.26, 95% CI: 0.14 to 0.49; I² = 0%), respectively. Non-antibiotic antimicrobial lock solutions probably reduced CRI per 1000 catheter-days for tunnelled CVC (9 studies: RR 0.60, 95% CI 0.40 to 0.91) but probably made little or no difference with non-tunnelled CVC (4 studies: RR 0.93, 95% CI 0.48 to 1.81). Subgroup analyses showed that antibiotic (5 studies: RR 0.76, 95% CI 0.42 to 1.38), non-antibiotic (8 studies: RR 0.85, 95% CI 0.44 to 1.66), and the combination of both lock solutions (3 studies: RR 0.63, 95% CI 0.22 to 1.81) made little or no difference to thrombosis per 1000 catheter-days compared to control lock solutions.

AUTHORS' CONCLUSIONS

Antibiotic antimicrobial and combined (antibiotic-non antibiotic) lock solutions decreased the incidence of CRI compared to control lock solutions, whereas non-antibiotic lock solutions reduce CRI only for tunnelled CVC. The effect on thrombosis incidence is uncertain for all antimicrobial lock solutions. Our confidence in the evidence is low and very low; therefore, better-designed studies are needed to confirm the efficacy and safety of antimicrobial lock solutions.

Anti-biofilm Activity as a Health Issue

The formation and persistence of surface-attached microbial communities, known as biofilms, are responsible for 75% of human microbial infections (National Institutes of Health). Biofilm lifestyle confers several advantages to the pathogens, notably during the colonization process of medical devices and/or patients’ organs. In addition, sessile bacteria have a high tolerance to exogenous stress including anti-infectious agents. Biofilms are highly competitive communities and some microorganisms exhibit anti-biofilm capacities such as bacterial growth inhibition, exclusion or competition, which enable them to acquire advantages and become dominant. The deciphering and control of anti-biofilm properties represent future challenges in human infection control. The aim of this review is to compare and discuss the mechanisms of natural bacterial anti-biofilm strategies/mechanisms recently identified in pathogenic, commensal and probiotic bacteria and the main synthetic strategies used in clinical practice, particularly for catheter-related infections.