Antiseptic-impregnated central venous catheters reduce the incidence of bacterial colonization and associated infection in immunocompromised transplant patients:

Practice Guidelines for Central Venous Access 2020

These practice guidelines update the Practice Guidelines for Central Venous Access: A Report by the American Society of Anesthesiologists Task Force on Central Venous Access, adopted by the American Society of Anesthesiologists in 2011 and published in 2012. These updated guidelines are intended for use by anesthesiologists and individuals under the supervision of an anesthesiologist and may also serve as a resource for other physicians, nurses, or healthcare providers who manage patients with central venous catheters.

Supplemental Digital Content is available in the text.

Intravascular Catheters and Biofilm Control

Intravascular catheters are the most common cause of nosocomially acquired bloodstream infections. Bacteria found adhering to the intraluminal surfaces of catheters are the principal source and cause of these infections. Adherent bacteria overtime are known to form multicellular communities which become encased within a three dimensional matrix of extracellular polymeric material known as biofilms, which are thought to be responsible for persistent infections. Consequently, a number of technologies have been developed to help prevent and control biofilms in intravascular catheters. One such approach involves impregnating catheter material with antimicrobial agents. Unfortunately these methods are not universally effective in preventing catheter-related biofilm infections. Technologies that utilise antimicrobials, as catheter locks have been shown to have more potential for preventing biofilm formation and reducing the incidences of catheter related bloodstream infections (CRBSI). This article discusses the significance of biofilms in intravascular catheters and determines whether the treatments available today are proving to be effective for controlling biofilms and draws attention to future avenues which are being investigated to control biofilms and therefore CRBSI.

Antimicrobially Impregnated Catheters: An Overview of Randomized Controlled Trials

In order to acquire an overview of the effectiveness of antimicrobially impregnated catheters on the prevention of catheter related bloodstream infections (CRI), we conducted a systematic review concentrating on randomized controlled trials (RCTs). The analysis end point was CRI; therefore, studies focussing only on catheter colonization were excluded. We did not consider abstracts for analysis. We identified 24 RCTs investigating the effectiveness of antimicrobially impregnated catheters. In addition, we discovered five meta-analyses and four studies investigating cost effectiveness. For the majority of antimicrobially impregnated catheter types only a few studies were available, and not enough to draw conclusions. Therefore, despite a relatively large number of RCTs available, the routine use of antimicrobially impregnated catheters as a measure for CRI prevention remains controversial, with a need for more high quality studies.

Comparative Efficacy of Antimicrobial Central Venous Catheters in Reducing Catheter-Related Bloodstream Infections in Adults: Abridged Cochrane Systematic Review and Network Meta-Analysis

Background

The efficacy of antimicrobial central venous catheters (CVCs) remains questionable. In this network meta-analysis, we aimed to assess the comparative efficacy of antimicrobial CVC impregnations in reducing catheter-related infections in adults.

Methods

We searched 4 electronic databases (Medline, the Cochrane Central Register of Controlled Trials, Embase, CINAHL) and internet sources for randomized controlled trials, ongoing clinical trials, and unpublished studies up to August 2016. Studies that assessed CVCs with antimicrobial impregnation with nonimpregnated catheters or catheters with another impregnation were included. Primary outcomes were clinically diagnosed sepsis, catheter-related bloodstream infection (CRBSI), and all-cause mortality. We performed a network meta-analysis to estimate risk ratio (RR) with 95% confidence interval (CI).

Results

Sixty studies with 17255 catheters were included. The effects of 14 impregnations were investigated. Both CRBSI and catheter colonization were the most commonly evaluated outcomes. Silver-impregnated CVCs significantly reduced clinically diagnosed sepsis compared with silver-impregnated cuffs (RR, 0.54 [95% CI, .29-.99]). When compared to no impregnation, significant CRBSI reduction was associated with minocycline-rifampicin (RR, 0.29 [95% CI, .16-.52]) and silver (RR, 0.57 [95% CI, .38-.86]) impregnations. No impregnations significantly reduced all-cause mortality. For catheter colonization, significant decreases were shown by miconazole-rifampicin (RR, 0.14 [95% CI, .05-.36]), 5-fluorouracil (RR, 0.34 [95% CI, .14-.82]), and chlorhexidine-silver sulfadiazine (RR, 0.60 [95% CI, .50-.72]) impregnations compared with no impregnation. None of the studies evaluated antibiotic/antiseptic resistance as the outcome.

Conclusions

Current evidence suggests that the minocycline-rifampicin-impregnated CVC appears to be the most effective in preventing CRBSI. However, its overall benefits in reducing clinical sepsis and mortality remain uncertain. Surveillance for antibiotic resistance attributed to the routine use of antimicrobial-impregnated CVCs should be emphasized in future trials.

Chlorhexidine and silver sulfadiazine coating on central venous catheters is not sufficient for protection against catheter-related infection: Simulation-based laboratory research with clinical validation

Objective The efficacy of chlorhexidine- and silver sulfadiazine-coated central venous catheters (CSS-CVC) against catheter-related infection remains controversial. We hypothesized that the loss of silver nanoparticles may reduce the antibacterial efficacy of CSS-CVCs and that this loss could be due to the frictional force between the surface of the CVC and the bloodstream. The objective of this study was to investigate whether the antimicrobial effect of CSS-CVCs decreases with increasing exposure time in a bloodstream model and quantitatively assay the antimicrobial effect of CSS-CVCs compared with polyurethane and antiseptic-impregnated CVCs. Methods Each CVC was subjected to 120 hours of saline flow and analyzed at intervals over 24 hours. The analyses included energy-dispersive X-ray spectroscopy, scanning electron microscopy, and optical density after a Staphylococcus aureus incubation test. Results The weight percentage of silver in the CSS-CVCs significantly decreased to 56.18% (44.10% ± 3.32%) with 48-hour catheterization and to 18.88% (14.82% ± 1.33%) with 120-hour catheterization compared with the initial weight percentage (78.50% ± 6.32%). In the S. aureus incubation test, the antibacterial function of CSS-CVCs was lost after 48 hours [3 (N/D) of OD]. Similar results were observed in a pilot clinical study using 18 CSS-CVCs. Conclusions We found that the efficacy of CSS-CVCs decreased over time and that the antibacterial function was lost after 48 hours of simulated wear-out. Therefore, antibiotic-impregnated CVCs may be a better option when longer (>48 hours) indwelling is needed.

Catheter impregnation, coating or bonding for reducing central venous catheter-related infections in adults

BACKGROUND

The central venous catheter (CVC) is essential in managing acutely ill patients in hospitals. Bloodstream infection is a major complication in patients with a CVC. Several infection control measures have been developed to reduce bloodstream infections, one of which is impregnation of CVCs with various forms of antimicrobials (either with an antiseptic or with antibiotics). This review was originally published in June 2013 and updated in 2016.

OBJECTIVES

Our main objective was to assess the effectiveness of antimicrobial impregnation, coating or bonding on CVCs in reducing clinically-diagnosed sepsis, catheter-related blood stream infection (CRBSI), all-cause mortality, catheter colonization and other catheter-related infections in adult participants who required central venous catheterization, along with their safety and cost effectiveness where data were available. We undertook the following comparisons: 1) catheters with antimicrobial modifications in the form of antimicrobial impregnation, coating or bonding, against catheters without antimicrobial modifications and 2) catheters with one type of antimicrobial impregnation against catheters with another type of antimicrobial impregnation. We planned to analyse the comparison of catheters with any type of antimicrobial impregnation against catheters with other antimicrobial modifications, e.g. antiseptic dressings, hubs, tunnelling, needleless connectors or antiseptic lock solutions, but did not find any relevant studies. Additionally, we planned to conduct subgroup analyses based on the length of catheter use, settings or levels of care (e.g. intensive care unit, standard ward and oncology unit), baseline risks, definition of sepsis, presence or absence of co-interventions and cost-effectiveness in different currencies.

SEARCH METHODS

We used the standard search strategy of the Cochrane Anaesthesia, Critical and Emergency Care Review Group (ACE). In the updated review, we searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 3), MEDLINE (OVID SP; 1950 to March 2015), EMBASE (1980 to March 2015), CINAHL (1982 to March 2015), and other Internet resources using a combination of keywords and MeSH headings. The original search was run in March 2012.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that assessed any type of impregnated catheter against either non-impregnated catheters or catheters with another type of impregnation in adult patients cared for in the hospital setting who required CVCs. We planned to include quasi-RCT and cluster-RCTs, but we identified none. We excluded cross-over studies.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methodological procedures expected by Cochrane. Two authors independently assessed the relevance and risk of bias of the retrieved records. We expressed our results using risk ratio (RR), absolute risk reduction (ARR) and number need to treat to benefit (NNTB) for categorical data and mean difference (MD) for continuous data, where appropriate, with their 95% confidence intervals (CIs).

MAIN RESULTS

We included one new study (338 participants/catheters) in this update, which brought the total included to 57 studies with 16,784 catheters and 11 types of impregnations. The total number of participants enrolled was unclear, as some studies did not provide this information. Most studies enrolled participants from the age of 18, including patients in intensive care units (ICU), oncology units and patients receiving long-term total parenteral nutrition. There were low or unclear risks of bias in the included studies, except for blinding, which was impossible in most studies due to the catheters that were being assessed having different appearances. Overall, catheter impregnation significantly reduced catheter-related blood stream infection (CRBSI), with an ARR of 2% (95% CI 3% to 1%), RR of 0.62 (95% CI 0.52 to 0.74) and NNTB of 50 (high-quality evidence). Catheter impregnation also reduced catheter colonization, with an ARR of 9% (95% CI 12% to 7%), RR of 0.67 (95% CI 0.59 to 0.76) and NNTB of 11 (moderate-quality evidence, downgraded due to substantial heterogeneity). However, catheter impregnation made no significant difference to the rates of clinically diagnosed sepsis (RR 1.0, 95% CI 0.88 to 1.13; moderate-quality evidence, downgraded due to a suspicion of publication bias), all-cause mortality (RR 0.92, 95% CI 0.80 to 1.07; high-quality evidence) and catheter-related local infections (RR 0.84, 95% CI 0.66 to 1.07; 2688 catheters, moderate quality evidence, downgraded due to wide 95% CI).In our subgroup analyses, we found that the magnitudes of benefits for impregnated CVCs varied between studies that enrolled different types of participants. For the outcome of catheter colonization, catheter impregnation conferred significant benefit in studies conducted in ICUs (RR 0.70;95% CI 0.61 to 0.80) but not in studies conducted in haematological and oncological units (RR 0.75; 95% CI 0.51 to 1.11) or studies that assessed predominantly patients who required CVCs for long-term total parenteral nutrition (RR 0.99; 95% CI 0.74 to 1.34). However, there was no such variation for the outcome of CRBSI. The magnitude of the effects was also not affected by the participants' baseline risks.There were no significant differences between the impregnated and non-impregnated groups in the rates of adverse effects, including thrombosis/thrombophlebitis, bleeding, erythema and/or tenderness at the insertion site.

AUTHORS' CONCLUSIONS

This review confirms the effectiveness of antimicrobial CVCs in reducing rates of CRBSI and catheter colonization. However, the magnitude of benefits regarding catheter colonization varied according to setting, with significant benefits only in studies conducted in ICUs. A comparatively smaller body of evidence suggests that antimicrobial CVCs do not appear to reduce clinically diagnosed sepsis or mortality significantly. Our findings call for caution in routinely recommending the use of antimicrobial-impregnated CVCs across all settings. Further randomized controlled trials assessing antimicrobial CVCs should include important clinical outcomes like the overall rates of sepsis and mortality.

Device-Related Infections in Critically Ill Patients. Part I: Prevention of Catheter-Related Bloodstream Infections

Device utilization in critically ill patients is responsible for a high risk of complications such as catheter-related bloodstream infections (CRBSI), ventilator-associated pneumonia (VAP) and urinary tract infections (UTI). In this article we will review the current status of data regarding CRBSI prevention. General recommendations include staff education and use of a surveillance program with a restrictive antibiotic policy. Adequate time must be allowed for hand washing and barrier precautions must always be used during device manipulation. The routine changing of central catheters is not necessary and increases costs; it is necessary to decrease the handling of administration sets, to use a more careful insertion technique and less frequent set replacement. Antiseptic-coated catheters appear to reduce catheter colonization but their ability to prevent catheter-related infections requires further demonstration. More clinical trials are needed to verify the efficacy of measures to prevent CRBSI.

Catheter impregnation, coating or bonding for reducing central venous catheter-related infections in adults

BACKGROUND

The central venous catheter (CVC) is a commonly used device in managing acutely ill patients in the hospital. Bloodstream infections are major complications in patients who require a CVC. Several infection control measures have been developed to reduce bloodstream infections, one of which is CVC impregnated with various forms of antimicrobials (either with an antiseptic or with antibiotics).

OBJECTIVES

We aimed to assess the effects of antimicrobial CVCs in reducing clinically diagnosed sepsis, established catheter-related bloodstream infection (CRBSI) and mortality.

SEARCH METHODS

We used the standard search strategy of the Cochrane Anaesthesia Review Group (CARG). We searched MEDLINE (OVID SP) (1950 to March 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 3, 2012), EMBASE (1980 to March 2012), CINAHL (1982 to March 2012) and other Internet resources using a combination of keywords and MeSH headings.

SELECTION CRITERIA

We included randomized controlled trials that assessed any type of impregnated catheter against either non-impregnated catheters or catheters with another impregnation. We excluded cross-over studies.

DATA COLLECTION AND ANALYSIS

We extracted data using the standard methods of the CARG. Two authors independently assessed the relevance and risk of bias of the retrieved records. We expressed our results using risk ratio (RR), absolute risk reduction (ARR) and number need to treat to benefit (NNTB) for categorical data and mean difference (MD) for continuous data where appropriate with their 95% confidence intervals (CIs).

MAIN RESULTS

We included 56 studies with 16,512 catheters and 11 types of antimicrobial impregnations. The total number of participants enrolled was unclear as some studies did not provide this information. There were low or unclear risks of bias in the included studies, except for blinding, which was impossible in most studies due to different appearances between the catheters assessed. Overall, catheter impregnation significantly reduced CRBSI, with an ARR of 2% (95% CI 3% to 1%), RR of 0.61 (95% CI 0.51 to 0.73) and NNTB of 50. Catheter impregnation also reduced catheter colonization, with an ARR of 10% (95% CI 13% to 7%), RR of 0.66 (95% CI 0.58 to 0.75) and NNTB of 10. However, catheter impregnation made no significant difference to the rates of clinically diagnosed sepsis (RR 1.0 (95% CI 0.88 to 1.13)) and all-cause mortality (RR 0.88 (95% CI 0.75 to 1.05)).In our subgroup analyses, we found that the magnitudes of benefits for impregnated CVCs varied in studies that enrolled different types of participants. For the outcome of catheter colonization, catheter impregnation conferred significant benefit in studies conducted in intensive care units (ICUs) (RR 0.68 (95% CI 0.59 to 0.78)) but not in studies conducted in haematological and oncological units (RR 0.75 (95% CI 0.51 to 1.11)) or studies that assessed predominantly patients who required CVCs for long-term total parenteral nutrition (TPN)(RR 0.99 (95% CI 0.74 to 1.34)). However, there was no such variation for the outcome of CRBSI. The magnitude of the effects was also not affected by the participants' baseline risks.There were no significant differences between the impregnated and non-impregnated groups in the rates of adverse effects, including thrombosis/thrombophlebitis, bleeding, erythema and/or tenderness at the insertion site.

AUTHORS' CONCLUSIONS

This review confirms the effectiveness of antimicrobial CVCs in improving such outcomes as CRBSI and catheter colonization. However, the magnitude of benefits in catheter colonization varied according to the setting, with significant benefits only in studies conducted in ICUs. Limited evidence suggests that antimicrobial CVCs do not appear to significantly reduce clinically diagnosed sepsis or mortality. Our findings call for caution in routinely recommending the use of antimicrobial-impregnated CVCs across all settings. Further randomized controlled trials assessing antimicrobial CVCs should include important clinical outcomes like the overall rates of sepsis and mortality.

Controle de infecção relacionada a cateter venoso central impregnado com antissépticos: revisão integrativa

O uso de cateter venoso central é apontado como um dos principais fatores para infecção da corrente sanguínea. Objetiva-se, neste estudo, buscar evidências científicas sobre o controle de infecção relacionada ao cateter venoso central impregnado com antissépticos utilizado em pacientes adultos hospitalizados. Para seleção dos estudos, foram utilizadas as bases de dados LILACS, CINAHL e MEDLINE. Totalizaram-se nove artigos por meio da revisão integrativa da literatura. As publicações acerca da utilização de cateteres impregnados com antissépticos mostraram diferença estatisticamente significante quanto à redução da colonização microbiana. Entretanto, apenas um estudo demonstrou redução na ocorrência da infecção. Diante das análises dos estudos, há necessidade de pesquisas adicionais em diferentes populações de pacientes com a finalidade de efetuar generalizações.

Effectiveness of different central venous catheters for catheter-related infections: a network meta-analysis

We aimed to compare the effectiveness of various catheters for prevention of catheter-related infection and to evaluate whether specific catheters are superior to others for reducing catheter-related infections. We identified randomised, controlled trials that compared different types of central venous catheter (CVC), evaluating catheter-related infections in a systematic search of articles published from January 1996 to November 2009 via Medline, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials. Network meta-analysis with a mixed treatment comparison method using Bayesian Markov Chain Monte Carlo simulation was used to combine direct within-trial, between-treatment comparisons with indirect trial evidence. Forty-eight clinical trials (12 828 CVCs) investigating 10 intervention catheters contributed to the analyses. For prevention of CVC colonisation, adjusted silver iontophoretic catheters (odds ratio: 0.58; 95% confidence interval: 0.33-0.95), chlorhexidine and silver sulfadiazine catheters (0.49; 0.36-0.64), chlorhexidine and silver sulfadiazine blue plus catheters (0.37; 0.17-0.69), minocycline-rifampicin catheters (0.28; 0.17-0.43) and miconazole-rifampicin catheters (0.11; 0.02-0.33) were associated with a significantly lower rate of catheter colonisation compared with standard catheters. For prevention of CRBSI, adjusted heparin-bonded catheters (0.20; 0.06-0.44) and minocycline-rifampicin catheters (0.18; 0.08-0.34) were associated with a significantly lower rate of CRBSI with standard catheters. Rifampicin-based impregnated catheters seem to be better for prevention of catheter-related infection compared with the other catheters.

The clinical effectiveness of central venous catheters treated with anti-infective agents in preventing catheter-related bloodstream infections: a systematic review

OBJECTIVES

To assess the clinical effectiveness of central venous catheters (CVCs) treated with anti-infective agents (AI-CVCs) in preventing catheter-related bloodstream infections (CRBSI).

DATA SOURCES

MEDLINE (OVID), EMBASE, SCI//Web of Science, SCI/ISI Proceedings, and the Cochrane Library.

STUDY SELECTION

A systematic review of the literature was conducted using internationally recognized methodology. All included articles were reports of randomized controlled trials comparing the clinical effectiveness of CVCs treated with AI-CVCs with either standard CVCs or another anti-infective treated catheter. Articles requiring in-house preparation of catheters or that only reported interim data were excluded.

DATA EXTRACTION

Data extraction was carried out independently and crosschecked by two reviewers using a pretested data extraction form.

DATA SYNTHESIS

Meta-analyses were conducted to assess the effectiveness of AI-CVCs in preventing CRBSI, compared with standard CVCs. Results are presented in forest plots with 95% confidence intervals.

RESULTS

Thirty-eight randomized controlled trials met the inclusion criteria. Methodologic quality was generally poor. Meta-analyses of data from 27 trials assessing CRBSI showed a strong treatment effect in favor of AI-CVCs (odds ratio 0.49 (95% confidence interval 0.37-0.64) fixed effects, test for heterogeneity, chi-square = 28.78, df = 26, p = 0.321, I = 9.7). Results subgrouped by the different types of anti-infective treatments generally demonstrated treatment effects favoring the treated catheters. Sensitivity analyses investigating the effects of methodologic differences showed no differences to the overall conclusions of the primary analysis.

CONCLUSION

AI-CVCs appear to be effective in reducing CRBSI compared with standard CVCs. However, it is important to establish whether this effect remains in settings where infection-prevention bundles of care are established as routine practice. This review does not address this question and further research is required.

Catheter-Related Bloodstream Infection in the Intensive Care Unit

Catheter-related bloodstream infection (CRBSI) is a significant cause of morbidity and mortality in the intensive care unit, contributing to prolonged stay with the associated cost and resource implications. Various mechanisms of infection have been suggested, and consequently, numerous interventions to reduce the burden of infection have been proposed, the efficacy of most of which remains controversial. The practice of routine catheter change and preferential use of the subclavian vein insertion site are both associated with an increased risk of mechanical complications, which may outweigh any potential benefit. Additionally, the use of silver- and antiseptic-impregnated catheters, of questionable benefit in the ICU patient population, is also argued to be unjustified in terms of efficacy and cost.

A small scale study in a London university district general hospital ICU found that while infection rates were low, the majority of infections were caused by Staphylococcus epidermidis and thus were probably a result of contamination either from the patient's commensal flora or acquired by contamination from healthcare workers. In accordance with published findings, this suggests that preventing contamination will decrease infection rates. Strict aseptic technique and the use of sterile fields during insertion are most likely the main contributors in reducing rates of infection. This together with education of staff across disciplines and adherence to local guidelines are likely to be the mainstays of reducing CRBSI in the ICU.

A systematic review comparing the relative effectiveness of antimicrobial-coated catheters in intensive care units

BACKGROUND

Bloodstream infection related to a central venous catheter is a substantial clinical and economic problem. To develop policy for managing the risks of these infections, all available evidence for prevention strategies should be synthesized and understood.

METHODS

We evaluate evidence (1985-2006) for short-term antimicrobial-coated central venous catheters in lowering rates of catheter-related bloodstream infection (CRBSI) in the adult intensive care unit. Evidence was appraised for inclusion against predefined criteria. Data extraction was by 2 independent reviewers. Thirty-four studies were included in the review. Antiseptic, antibiotic, and heparin-coated catheters were compared with uncoated catheters and one another. Metaanalysis was used to generate summary relative risks for CRBSI and catheter colonization by antimicrobial coating.

RESULTS

Externally impregnated chlorhexidine/silver sulfadiazine catheters reduce risk of CRBSI relative to uncoated catheters (RR, 0.66; 95% CI: 0.47-0.93). Minocycline and rifampicin-coated catheters are significantly more effective relative to CHG/SSD catheters (RR, 0.12; 95% CI: 0.02-0.67). The new generation chlorhexidine/silver sulfadiazine catheters and silver, platinum, and carbon-coated catheters showed nonsignificant reductions in risk of CRBSI compared with uncoated catheters.

CONCLUSION

Two decades of evidence describe the effectiveness of antimicrobial catheters in preventing CRBSI and provide useful information about which catheters are most effective. Questions surrounding their routine use will require supplementation of this trial evidence with information from more diverse sources.

Intravascular catheter-related infections: advances in diagnosis, prevention, and management

Indwelling vascular catheters are a leading source of bloodstream infections in critically ill patients and cancer patients. Because clinical diagnostic criteria are either insensitive or non-specific, such infections are often overdiagnosed, resulting in unnecessary and wasteful removal of the catheter. Catheter-sparing diagnostic methods, such as differential quantitative blood cultures and time to positivity have emerged as reliable diagnostic techniques. Novel preventive strategies include cutaneous antisepsis, maximum sterile barrier, use of antimicrobial catheters, and antimicrobial catheter lock solution. Management of catheter-related bloodstream infections involves deciding on catheter removal, antimicrobial catheter lock solution, and the type and duration of systemic antimicrobial therapy. Such decisions depend on the identity of the organism causing the bloodstream infection, the clinical and radiographical manifestations suggesting a complicated course, the underlying condition of the host (neutropenia, thrombocytopenia), and the availability of other vascular access sites.

Effect of Chlorhexidine/Silver Sulfadiazine-Impregnated Central Venous Catheters in an Intensive Care Unit with a Low Blood Stream Infection Rate after Implementation of an Educational Program: A Before–After Trial

BACKGROUND

Current guidelines recommend using antiseptic- or antibiotic-impregnated central venous catheters (CVCs) if, following a comprehensive strategy to prevent catheter-related blood stream infection (CR-BSI), infection rates remain above institutional goals based on benchmark values. The purpose of this study was to determine if chlorhexidine/silver sulfadiazine-impregnated CVCs could decrease the CR-BSI rate in an intensive care unit (ICU) with a low baseline infection rate.

METHODS

Pre-intervention and post-intervention observational study in a 24-bed surgical/trauma/burn ICU from October, 2002 to August, 2005. All patients requiring CVC placement after March, 2004 had a chlorhexidine/silver sulfadiazine-impregnated catheter inserted (post-intervention period).

RESULTS

Twenty-three CR-BSIs occurred in 6,960 catheter days (3.3 per 1,000 catheter days)during the 17-month control period. After introduction of chlorhexidine/silver sulfadiazine-impregnated catheters, 16 CR-BSIs occurred in 7,732 catheter days (2.1 per 1,000 catheter days; p = 0.16). The average length of time required for an infection to become established after catheterization was similar in the two groups (8.4 vs. 8.6 days; p = 0.85). Chlorhexidine/silver sulfadiazine-impregnated catheters did not result in a statistically significant change in the microbiological profile of CR-BSIs, nor did they increase the incidence of resistant organisms.

CONCLUSIONS

Although chlorhexidine/silver sulfadiazine-impregnated catheters are useful in specific patient populations, they did not result in a statistically significant decrease in the CR-BSI rate in this study, beyond what was achieved with education alone.

An update on antimicrobial central venous catheters

Antimicrobial central venous catheters make use of a variety of antimicrobial mechanisms. Although they are currently infrequently used and their role in preventing infection is still being defined, they have a clear application in certain situations.

Comparison of silver-impregnated with standard multi-lumen central venous catheters in critically ill patients*

OBJECTIVES

To evaluate a new silver-impregnated multi-lumen central venous catheter for reducing catheter-related colonization in intensive care patients.

DESIGN

Multicenter, prospective, randomized, controlled clinical study.

SETTING

Ten adult intensive care units (multidisciplinary, medical and surgical, university and nonuniversity hospitals) in eight institutions.

PATIENTS

A total of 577 patients who required 617 multi-lumen central venous catheters between November 2002 and April 2004 were studied.

INTERVENTIONS

Intensive care adult patients requiring multi-lumen central venous catheters expected to remain in place for >or=3 days were randomly assigned to undergo insertion of silver-impregnated catheters (silver group) or standard catheters (standard group). Catheter colonization was defined as the growth of >or=1,000 colony-forming units in culture of the intravascular tip of the catheter by the vortexing method. Diagnosis of catheter-related infection was performed by an independent and blinded expert committee.

RESULTS

A total of 320 catheters were studied in the silver group and 297 in the standard group. Characteristics of the patients, insertion site, duration of catheterization (median, 11 vs. 10 days), and other risk factors for infection were similar in the two groups. Colonization of the catheter occurred in 47 (14.7%) vs. 36 (12.1%) catheters in the silver and the standard groups (p = .35), for an incidence of 11.2 and 9.4 per 1,000 catheter days, respectively. Catheter-related bloodstream infection was recorded in eight (2.5%) vs. eight (2.7%) catheters in the silver and the standard groups (p = .88), for an incidence of 1.9 and 2.1 per 1,000 catheter days, respectively.

CONCLUSION

The use of silver-impregnated multi-lumen catheters in adult intensive care patients is not associated with a lower rate of colonization than the use of standard multi-lumen catheters.

Antimicrobial impregnated catheters in the prevention of catheter-related bloodstream infection in hospitalized patients

Catheter-related bloodstream infections have a significant impact on increasing health care costs and morbidity and mortality in hospitalized patients. Many technologies have been created in an attempt to decrease the incidence of catheter-related bloodstream infection. One of these is the impregnation of central venous catheters with antiseptics (e.g., chlorhexidine and silver sulfadiazine) or antibiotics (e.g., minocycline and rifampin). While studies evaluating the efficacy of impregnated catheters have been conducted, the data are limited and their use remains variable across institutions. This paper will discuss catheter-related factors that predispose patients to catheter-related bloodstream infection, the types of antimicrobial-impregnated catheters in use today, studies evaluating their efficacy, and common concerns associated with the use of these catheters. Issues related to the cost-effectiveness of impregnated catheters and future directions for the prevention of catheter-related bloodstream infection will also be presented.

Central venous catheter colonization in critically ill patients: a prospective, randomized, controlled study comparing standard with two antiseptic-impregnated catheters

In this prospective, randomized, controlled, unblinded study, we compared colonization rates of a standard, unimpregnated central venous catheter (CVC) with rates for silver-coated and chlorhexidine-silversulfadiazine (CH-SS)-impregnated CVC. Patient characteristics, CVC insertion site, indwelling time, and colonization detected by semiquantitative and quantitative microbiologic techniques were documented. Two-hundred-seventy-five critically ill patients were included into the study protocol. One-hundred-sixty standard, 160 silver (S)-coated, and 165 externally impregnated CH-SS CVC were inserted. There was a significant difference in CVC colonization rates among study groups (P = 0.029). There was no difference in the colonization rate and the colonization per 1000 catheter days between standard and S-coated (P = 0.564; P = 0.24) or CH-SS-coated CVC (P= 0.795; P = 0.639). When comparing antiseptic CVC with each other, colonization rates were significantly less with CH-SS-impregnated than with S-coated CVC (16.9% versus 7.3%; P = 0.01; 18.2 versus 7.5 of 1000 catheter days; P = 0.003; relative risk, 0.43; 95% confidence interval, 0.21-0.85). Whereas standard and S-coated CVC were first colonized 2 and 3 days after insertion, respectively, CH-SS CVC were first colonized only after 7 days. In conclusion, antiseptic-impregnated CVC could not prevent catheter colonization when compared with standard polyurethane catheters in a critical care setting with infrequent catheter colonization rates and CVC left in place for >10 days.

Drug/device combinations for local drug therapies and infection prophylaxis

Combination devices-those comprising drug releasing components together with functional prosthetic implants-represent a versatile, emerging clinical technology promising to provide functional improvements to implant devices in several classes. Landmark antimicrobial catheters and the drug-eluting stent have heralded the entrance, and significantly, routes to FDA approval, for these devices into clinical practice. This review describes recent strategies creating implantable combination devices. Most prominent are new combination devices representing current orthopedic and cardiovascular implants with new added capabilities from on-board or directly associated drug delivery systems are now under development. Wound coverings and implantable sensors will also benefit from this combination enhancement. Infection mitigation, a common problem with implantable devices, is a current primary focus. On-going progress in cell-based therapeutics, progenitor cell exploitation, growth factor delivery and advanced formulation strategies will provide a more general and versatile basis for advanced combination device strategies. These seek to improve tissue-device integration and functional tissue regeneration. Future combination devices might best be completely re-designed de novo to deliver multiple bioactive agents over several spatial and temporal scales to enhance prosthetic device function, instead of the current 'add-on' approach to existing implant device designs never originally intending to function in tandem with drug delivery systems.

Chlorhexidine-impregnated dressing for prevention of colonization of central venous catheters in infants and children: a randomized controlled study

BACKGROUND

Infections of short term, nontunneled, intravascular catheters are often caused by migration of organisms from the insertion site. The aim of this study was to evaluate the effectiveness and safety of a chlorhexidine gluconate-impregnated dressing for the reduction of central venous catheter (CVC) colonization and CVC-associated bloodstream infections in infants and children after cardiac surgery.

METHODS

This prospective, randomized, controlled study was conducted in the pediatric cardiac intensive care unit of a tertiary care pediatric medical center. Patients 0-18 years of age who were admitted to the pediatric cardiac intensive care unit during a 14-month period and required a CVC for >48 hours were randomized to receive a transparent polyurethane insertion site dressing (control group) or a chlorhexidine gluconate-impregnated sponge (Biopatch) dressing covered by a transparent polyurethane dressing (study group). The main outcome measures were rates of bacterial colonization, rates of CVC-associated bloodstream infections and adverse events.

RESULTS

Seventy-one patients were randomized to the control group and 74 to the study group. There were no significant between group differences in age, sex, Pediatric Risk of Mortality score or cardiac severity score. CVC colonization occurred in 21 control patients (29%) and 11 (14.8%) study patients (P = 0.0446; relative risk, 0.6166; 95% confidence interval, 0.3716-1.023). Bloodstream infection occurred in 3 patients (4.2%) in the control group and 4 patients (5.4%) in the study group. Local redness was noted in 1 control patient and 4 study group patients.

CONCLUSIONS

The chlorhexidine gluconate-impregnated sponge is safe and significantly reduces the rates of CVC colonization in infants and children after cardiac surgery.

Infections associated with medical devices: pathogenesis, management and prophylaxis

The insertion or implantation of foreign bodies has become an indispensable part in almost all fields of medicine. However, medical devices are associated with a definitive risk of bacterial and fungal infections. Foreign body-related infections (FBRIs), particularly catheter-related infections, significantly contribute to the increasing problem of nosocomial infections. While a variety of micro-organisms may be involved as pathogens, staphylococci account for the majority of FBRIs. Their ability to adhere to materials and to promote formation of a biofilm is the most important feature of their pathogenicity. This biofilm on the surface of colonised foreign bodies is regarded as the biological correlative for the clinical experience with FBRI, that is, that the host defence mechanisms often seem to be unable to handle the infection and, in particular, to eliminate the micro-organisms from the infected device. Since antibacterial chemotherapy is also frequently not able to cure these infections despite the use of antibacterials with proven in vitro activity, removal of implanted devices is often inevitable and has been standard clinical practice. However, in specific circumstances, such as infections of implanted medical devices with coagulase-negative staphylococci, a trial of salvage of the device may be justified. All FBRIs should be treated with antibacterials to which the pathogens have been shown to be susceptible. In addition to systemic antibacterial therapy, an intraluminal application of antibacterial agents, referred to as the 'antibiotic-lock' technique, should be considered to circumvent the need for removal, especially in patients with implanted long-term catheters. To reduce the incidence of intravascular catheter-related bloodstream infections, specific guidelines comprising both technological and nontechnological strategies for prevention have been established. Quality assurance, continuing education, choice of the catheter insertion site, hand hygiene and aseptic techniques are aspects of particular interest. Furthermore, all steps in the pathogenesis of biofilm formation may represent targets against which prevention strategies may be directed. Alteration of the foreign body material surface may lead to a change in specific and nonspecific interactions with micro-organisms and, thus, to a reduced microbial adherence. Medical devices made out of a material that would be antiadhesive or at least colonisation resistant would be the most suitable candidates to avoid colonisation and subsequent infection. Another concept for the prevention of FBRIs involves the impregnation of devices with various substances such as antibacterials, antiseptics and/or metals. Finally, further studies are needed to translate the knowledge on the mechanisms of biofilm formation into applicable therapeutic and preventive strategies.

Chlorhexidine and silver-sulfadiazine coated central venous catheters in haematological patients--a double-blind, randomised, prospective, controlled trial

BACKGROUND

Central venous catheters (CVCs) are essential for the intensive care of patients with haematological illness. Catheter-related infections (CRI) are an important problem in modern medicine, which may lead to life-threatening situations, to prolonged hospitalisation and increased cost. In immunocompromised patients suffering from haemato-oncological diseases, CRI is a significant factor for adverse outcome. Several clinical studies have shown that CVCs coated with antiseptics such as chlorhexidine and silver-sulfadiazine (CHSS) reduce the risk of catheter-related bacteraemia. Most studies, however, were performed on intensive care patients not suffering from chemotherapy-induced immunosuppression.

PATIENTS AND METHODS

A prospective double-blind, randomised, controlled trial was performed to investigate the effectiveness of CHSS-coated catheters in haemato-oncological patients. A total number of 184 catheters (median duration of placement, 11 days) were inserted into 184 patients (male 115, female 69), of which 90 were antiseptically coated. After removal, all catheters were investigated for bacterial growth.

MAIN RESULTS

Catheters coated with CHSS were effective in reducing the rate of significant bacterial growth on either the tip or subcutaneous segment (26%) compared to control catheters (49%). The incidence of catheter colonisation was also significantly reduced (12% coated vs 33% uncoated). Data obtained show a significant reduction of catheter colonisation in CHSS catheters. There was no significant difference in the incidence of catheter-related bacteraemia (3% coated vs 7% uncoated). However, due to the overall low rate of CRI, we could not observe a significant reduction in the incidence of catheter-related bacteraemia.

CONCLUSION

Our data show that the use of CHSS catheters in patients with haematological malignancy reduces the overall risk of catheter colonisation and CRI, although the incidence of catheter-related bacteremia was similar in both groups.

A rapid method of impregnating endotracheal tubes and urinary catheters with gendine: a novel antiseptic agent

OBJECTIVES

To test the efficacy of gendine, a novel antiseptic, containing Gentian Violet and chlorhexidine, in coating different medical devices, including endotracheal tubes (ETT) and urinary catheters (UC).

METHODS

We determined the antimicrobial efficacy and cytotoxicity of ETT and UC segments coated, through an instant dip method, with gendine. Using the modified Kirby-Bauer method, gendine-coated devices showed zones of inhibition of >/=15 mm against methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Escherichia coli and Candida parapsilosis.

RESULTS

Gendine-coated endotracheal tubes (GND-ETT) soaked in bronchoalveolar fluid (BAL) and incubated at 37 degrees C maintained a zone of inhibition of >/=15 mm against MRSA and P. aeruginosa for at least 3 weeks. Similarly, gendine-coated urinary catheters (GND-UC), soaked in urine, maintained a zone of inhibition of >/=15 mm against E. coli for 8 weeks. Using the minimum essential media elution method in mouse fibroblast cells, GND-ETT and GND-UC were found to be non-cytotoxic. Gendine-coated UC significantly reduced the amount of viable MRSA, E. coli or C. parapsilosis organisms adhering to their surfaces when compared with silver/hydrogel-coated urinary catheters or control uncoated catheters (P < 0.01). Similarly GND-ETT significantly reduced the adherence of the same organisms as well as P. aeruginosa when compared with control (P </= 0.02).

CONCLUSIONS

GND-ETT and GND-UC impregnated using an instantaneous dip method, were shown to have broad-spectrum activity, prolonged antimicrobial durability and high efficacy in inhibiting adherence of organisms commonly causing nosocomial pneumonia and urinary tract infection. Furthermore, these coated devices were shown to be non-cytotoxic.

Reduction of catheter-related infections in neutropenic patients: a prospective controlled randomized trial using a chlorhexidine and silver sulfadiazine-impregnated central venous catheter

Antiseptic coating of intravascular catheters may be an effective means of decreasing catheter-related colonization and subsequent infection. The purpose of this study was to assess the efficacy of chlorhexidine and silver sulfadiazine (CH-SS)-impregnated central venous catheters (CVCs) to prevent catheter-related colonization and infection in patients with hematological malignancies who were subjected to intensive chemotherapy and suffered from severe and sustained neutropenia. Proven CVC-related bloodstream infection (BSI) was defined as the isolation of the same species from peripheral blood culture and CVC tip (Maki technique). This randomized, prospective clinical trial was carried out in 106 patients and compared catheter-related colonization and BSI using a CH-SS-impregnated CVC (n=51) to a control arm using a standard uncoated triple-lumen CVC (n=55). Patients were treated for acute leukemia (n=89), non-Hodgkin's lymphoma (n=10), and multiple myeloma (n=7). Study groups were balanced regarding to age, sex, underlying diseases, insertion site, and duration of neutropenia. The CVCs were in situ a mean of 14.3+/-8.2 days (mean+/-SD) in the study group versus 16.6+/-9.7 days in the control arm. Catheter-related colonization was observed less frequently in the study group (five vs nine patients; p=0.035). CVC-related BSI were significantly less frequent in the study group (one vs eight patients; p=0.02). In summary, in patients with severe neutropenia, CH-SS-impregnated CVCs yield a significant antibacterial effect resulting in a significantly lower rate of catheter-related colonization as well as CVC-related BSI.

Do antimicrobial-impregnated central venous catheters prevent catheter-related bloodstream infection?

Controversy surrounds the role of central venous catheters (CVCs) impregnated with antimicrobial agents in the prevention of catheter-related bloodstream infection (CRBSI). We reviewed the current literature to evaluate the efficacy of antimicrobial-impregnated CVCs for preventing CRBSI. Eleven randomized studies published in article form were identified that included a control group that received nonimpregnated CVCs. We evaluated study methodologies, inclusion of key patient characteristics, use of clinically relevant end points, and molecular-relatedness studies. Review of these 11 trials revealed several methodological flaws, including inconsistent definitions of CRBSI, failure to account for confounding variables, suboptimal statistical and epidemiological methods, and rare use of clinically relevant end points. This review also failed to demonstrate any significant clinical benefit associated with the use of antimicrobial-impregnated CVCs for the purpose of reducing CRBSI or improving patient outcomes. More rigorous studies are required to support or refute the hypothesis that antimicrobial-impregnated CVCs reduce the rate of or prevent CRBSI.

Effect of central venous catheter type on infections: a prospective clinical trial

This study reports on a block clinical trial of two types of central venous catheters (CVCS): antiseptic-impregnated catheters (AIC) and non-impregnated catheters (non-AIC), on catheter tip colonization and bacteraemia. In total, 500 catheters were inserted in 390 patients over the 18 month study period, 260 (52.0%) AIC and 240 (48.0%) non-AIC. Of these, 460 (92.0%) tips (237 AIC and 223 non-AIC) were collected. While significantly fewer AIC, 14 (5.9%), than non-AIC, 30 (13.5%), catheters were colonized (P<0.01), there was no difference in the rates of bacteraemias in the two groups (0.8% vs. 2.7%, respectively, P=0.16). There were 6.87 (95% CI 3.38-14.26) and 16.92 (95% CI 10.61-27.12) colonized AIC and non-AIC catheters, respectively, per 1000 catheter days, a difference that was significant (P<0.01). However, no difference emerged between bacteraemias in AIC and non-AIC catheters per 1000 catheter days measured at 0.98 (95% CI 0.24-5.54) and 3.38 (95% CI 1.29-9.34), respectively (P=0.10). Of the 444 CVCs that were sited in the subclavian or jugular veins and had tips collected, significantly more catheters were colonized in the jugular group, 19 (20%), compared with the subclavian group, 24 (6.9%; P< or =0.01). Overall, the low rates of colonization and bacteraemia may be explained by the population studied, the policies used and the employment of a clinical nurse dedicated to CVC management.

The relationship between methodological trial quality and the effects of impregnated central venous catheters

OBJECTIVE

We assessed the methodological trial quality of individual randomized controlled studies on chlorhexidine silver sulfadiazine impregnated catheters and the effect on catheter-related infection (CRI).

DESIGN

Only the studies identified in the Medline database from 1966 to December 2001 were considered, abstracts being excluded. The outcome of this investigation centered on bloodstream CRI. The trial quality of the 11 studies identified and published (total 3,131 catheters) was assessed using a scoring system based on allocation, patient selection, patient characteristics, blinding of the intervention and the diagnosis of CRI (range 0-2 points, 10 points maximum).

RESULTS

The mean methodological quality score was 7.1 (range 5-9). The relative risk reduction for bloodstream CRI ranged from -0.14 to 1.0. No association between trial quality and the impact of chlorhexidine silver sulfadiazine impregnated catheters on CRI was found. The summary odds ratio for CRI was 0.69 (95% CI 0.46-1.03). Taking only those studies with 2 points for diagnosis of CRI a summary odds ratio of 0.87 (95% CI 0.44-1.72) resulted, whereas studies with a diagnosis score of only 1 point led to a summary odds ratio of 0.60 (95% CI 0.35-1.02).

CONCLUSIONS

The quality of the studies seems to have had no influence on the outcome, according to the results of this investigation, but the use of only a single quality score may not be sufficient to investigate the prevention effect of impregnated catheters.

Prevention of bloodstream infections with central venous catheters treated with anti-infective agents depends on catheter type and insertion time: evidence from a meta-analysis

OBJECTIVE

To test the evidence that the risk of infection related to central venous catheters (CVCs) is decreased by anti-infective coating or cuffing.

DESIGN

Systematic review of randomized, controlled trials comparing anti-infective with inactive (control) CVCs.

INTERVENTIONS

Average insertion times were taken as a measurement of the length of insertion. Dichotomous data were combined using a fixed effect model and expressed as odds ratio (OR) with 95% confidence interval (CI95).

RESULTS

Two trials on antibiotic coating (343 CVCs) had an average insertion time of 6 days; the risk of BSI decreased from 5.1% with control to 0% with anti-infective catheters. There were no trials with longer average insertion times. In three trials on silver collagen cuffs (422 CVCs), the average insertion time ranged from 5 to 8.2 days (median, 7 days); the risk of BSI was 5.6% with control and 3.2% with anti-infective catheters. In another trial on silver collagen cuffs (101 CVCs), the average insertion time was 38 days; the risk of BSI was 3.7% with control and 4.3% with anti-infective catheters. In five trials on chlorhexidine-silver sulfadiazine coating (1,269 CVCs), the average insertion time ranged from 5.2 to 7.5 days (median, 6 days); the risk of BSI decreased from 4.1% with control to 1.9% with anti-infective catheters. In five additional trials on chlorhexidine-silver sulfadiazine coating (1,544 CVCs), the average insertion time ranged from 7.8 to 20 days (median, 12 days); the risk of BSI was 4.5% with control and 4.2% with anti-infective catheters.

CONCLUSIONS

Antibiotic and chlorhexidine-silver sulfadiazine coatings are anti-infective for short (approximately 1 week) insertion times. For longer insertion times, there are no data on antibiotic coating, and there is evidence of lack of effect for chlorhexidine-silver sulfadiazine coating. For silver-impregnated collagen cuffs, there is evidence of lack of effect for both short- and long-term insertion.

Efficacy of subcutaneous tunneling for prevention of bacterial colonization of femoral central venous catheters in critically ill children

BACKGROUND

Blood stream infections are a common and serious complication of central venous catheters (CVCs). To decrease catheter colonization, some authors advocate tunneling the catheter in the subcutaneous tissue during insertion. This technique has proved effective in adults, but there are no data on its safety and efficacy in critically ill children. Our objective was to evaluate the efficacy and safety of subcutaneous tunneling of short term, noncuffed CVCs for the prevention of CVC-related infections in critically ill children.

METHODS

A prospective randomized controlled trial was performed at a tertiary children's medical center in Israel and included children ages 0 to 18 years admitted to the pediatric intensive care unit or the pediatric cardiac intensive care unit from September 2000 to April 2001 who required placement of a femoral central venous catheter for >48 h. The children were randomized for tunneled or nontunneled insertion. The main outcome measures were bacterial colonization of proximal and distal catheter segments tested by semiquantitative technique and infectious or noninfectious complications of the CVC.

RESULTS

Of 98 eligible children, 49 received tunneled catheters and 49 received nontunneled catheters. Patients' age ranged from 1 month to 16.5 years (mean, 3.07 +/- 2.48 years). There were no significant differences between the groups in age, sex, disease severity [Pediatric Risk of Mortality III (PRISM) score], duration of catheterization and underlying diseases. Bacterial colonization was found in 11 (22.4%) catheters in the nontunneled group compared with 3 (6.1%) in the tunneled group (P = 0.004). Proximal segment colonization occurred in 7 (14.2%) nontunneled catheters and 2 (4.8%) tunneled catheters (P = 0.07), and distal segment colonization occurred in 3 (6.1%) and 9(18.3%) tunneled and nontunneled catheters, respectively (P = 0.053). The main pathogens were coagulase-negative staphylococci, Pseudomonas spp. and Klebsiella spp. There was no statistically significant difference between the groups in the rate of bloodstream infection (2 in the tunneled group, 3 in the nontunneled). Except for 1 case of subcutaneous hematoma, which resolved, there were no immediate or late complications of the tunneling procedure.

CONCLUSION

Subcutaneous tunneling of CVCs in the femoral site is a safe procedure and decreases significantly the rate of CVC colonization in critically ill children.

Antibiofilm approaches: prevention of catheter colonization

Bacteria frequently attach to medical devices such as intravascular catheters by forming sessile multicellular communities known as biofilms, which can be the source of persistent infections that are recalcitrant to systemic antibiotic therapy. As a result of this persistence, a number of technologies have been developed to prevent catheter-associated biofilm formation. Whereas the most straightforward approaches focus on impregnating catheter material with classical antimicrobial agents, these approaches are not universally effective, thereby underscoring the need for more potent and more sophisticated approaches to the prevention of catheter-related biofilm infections.

Contamination of central venous catheters in immunocompromised patients: a comparison between two different types of central venous catheters

Catheters impregnated with silver have been proposed as a means of reducing catheter-related infection. We therefore performed a prospective randomized study to compare a new silver-impregnated central venous catheter (CVC) with a commercially available CVC in a cohort of immunocompromised patients. We studied 157 patients of whom 97 could be analysed. The median indwelling time in the study group (SC) was 10.5 days and 11 days in the control group (CC). The incidence of contamination in the SC group was 15.6 vs 24.6 in the CC group referring to 1000 catheter days. In both groups, we found 6% of catheter-related infections according to the definitions of a published scoring system. The differences between the two groups were not significant. We conclude that the SC decrease the incidence of catheter contamination and may have a positive effect on the reduction of CVC-related infections.

Antimicrobial-coated/bonded and -impregnated intravascular catheters

OBJECTIVE

To review the literature regarding the prevention of catheter colonization and catheter-related bloodstream infections (CRBIs) with the use of antimicrobial-coated/bonded and -impregnated intravascular catheters.

DATA SOURCES

Primary and review English-language literature were identified using MEDLINE (1966-September 2000) pertaining to the key terms antibiotic, antimicrobial, antiseptic, silver, and bonded, coated, Impregnated catheters. In addition, textbooks and relevant reference lists were reviewed.

DATA EXTRACTION

All articles identified through the data sources were evaluated. Information deemed relevant to the objectives of the review was included.

DATA SYNTHESIS

Significant morbidity and mortality are associated with the development of CRBIs. Preventative measures such as modification of these catheters with antimicrobial coating/bonding have produced varying results. Trials evaluating cefazolin, teicoplanin, vancomycin, silver, and chlorhexidine-silver sulfadiazine (C-SS) used for coated/bonded intravascular catheters have not demonstrated a consistent decrease in the incidence of CRBIs. However, a meta-analysis of trials evaluating C-SS intravascular catheters demonstrated a statistically significant reduction in CRBIs. A larger reduction in CRBIs has been reported with minocycline-rifampin (M-R) versus C-SS intravascular catheters. Use of the M-R and C-SS catheters may result in a cost savings of $100 million and reduce as many as 12,000 CRBI-related deaths annually when used short term (<7 d).

CONCLUSIONS

When used for short-term catheterization, M-R catheters appear to be superior to the currently available C-SS catheters at preventing CRBIs. Significant cost savings and reduction in mortality can be anticipated with the use of M-R catheters.

Prevention of nosocomial bloodstream infections: effectiveness of antimicrobial-impregnated and heparin-bonded central venous catheters

OBJECTIVES

To examine the effectiveness of antimicrobial-impregnated and heparin-bonded catheters relative to standard central venous catheters in lessening catheter-related bloodstream infections.

DATA SOURCES

Articles were identified by computer-assisted searching.

STUDY SELECTION

Studies were eliminated from further consideration if they did not contain original data relevant to lessening catheter-related bloodstream infections, were nonrandomized or uncontrolled, described subjects <17 yrs of age, or used animal subjects.

DATA ABSTRACTION

From each eligible article, we abstracted the following: a) citation; b) type of control; c) study setting; d) type of experimental catheter; e) catheter-specific complications; f) total numbers of patients and catheters; g) number of experimental catheters used that resulted in a catheter-related bloodstream infection; h) number of control catheters used that resulted in a catheter-related bloodstream infection; i) number of experimental catheters used without catheter-related bloodstream infections; and j) number of control catheters used without infections. We also recorded the duration of catheter use and the types of microbes cultured in association with the catheters and with catheter-related bloodstream infections.

DATA SYNTHESIS

Eleven eligible studies were identified. Using meta-analysis, we showed that antimicrobial-impregnated and heparin-bonded central venous catheters significantly decreased catheter-related bloodstream infections by 2.32% (95% confidence interval, 1.04% to 3.61%).

CONCLUSIONS

The modest additional cost for the use of these catheters relative to the considerable cost of treating even a single bloodstream infection makes their use cost-effective.

The clinical and economic consequences of nosocomial central venous catheter-related infection: are antimicrobial catheters useful?

Central venous catheters (CVCs) are essential for many hospitalized patients, but they are associated with important infectious complications. Recent studies have indicated that CVCs coated with antimicrobial agents reduce the incidence of catheter-related bloodstream infection (CR BSI). To estimate the clinical and economic consequences of short-term central venous catheter-related infection and the potential usefulness of antimicrobial-coated catheters, we reviewed and synthesized the available relevant literature. Statistical pooling was used to estimate the incidence of both catheter colonization and CR BSI. The attributable mortality of CR BSI was also evaluated. In addition, the economic consequences of both local and systemic catheter-related infection was estimated from literature reports that used micro-costing and other techniques. Among patients in whom standard, noncoated CVCs are in place for an average of 8 days, 24.7% are expected to develop catheter colonization (95% confidence interval [CI(95)], 22.0%-27.5%). Approximately 5.2% (CI(95), 3.9%-6.5%) will develop CR BSI. The attributable mortality of CR BSI remains unclear, but recent studies are consistent with a range from 4% to 20%. An episode of local catheter-related infection leads to an additional cost of approximately $400, whereas the additional cost of CR BSI ranges from approximately $6,005 to $9,738. Formal economic analyses indicate that CVCs coated with antibacterial agents (such as chlorhexidine-silver sulfadiazine or minocycline-rifampin) likely reduce infectious complications, yielding economic advantages. In light of the substantial clinical and economic burden of catheter-related infection, hospital personnel should adopt proven cost-effective methods to reduce this common and important nosocomial complication.

Antiseptic-bonded central venous catheters and bacterial colonisation

This study was undertaken to evaluate the impact of chlorhexidine/silver sulphadiazine-bonded catheters on the incidence of colonisation and catheter-related sepsis in critically ill patients. Threehundred and fifty-one catheters were inserted into 228 patients during the study period, 174chlorhexidine/silver sulphadiazine-bonded catheters and 177 standard catheters. Indications for catheter removal were: death, clinical redundancy and clinical evidence of local or systemic infection. All catheter tips were sent to the microbiology laboratory for semiquantitative analysis of bacterial colony count. Seventy-one (40.2%) of the standard catheters and 47 (27.2%) of the antiseptic-bonded catheters were found to be colonised on removal (p < 0.01). Eight cases (4.7%) of catheter-related sepsis were associated with standard catheters and three cases (1.7%) with antiseptic-bonded catheters, however, this reduction was not statistically significant. Our results indicate that the use of antiseptic-bonded catheters in critically ill patients significantly reduces the incidence of bacterial colonisation.