A prospective, randomized trial of rifampicin-minocycline-coated and silver-platinum-carbon-impregnated central venous catheters*

The use of rifampicin-miconazole-impregnated catheters reduces the incidence of femoral and jugular catheter-related bacteremia

BACKGROUND

The guidelines of the Centers for Disease Control and Prevention do not recommend the use of an antimicrobial- or antiseptic-impregnated catheter for short-term use. In previous studies, we have found a higher incidence of central venous catheter-related bacteremia among patients with femoral and central jugular accesses than among patients with other venous accesses.

OBJECTIVE

The objective of our study was to determine the incidence of central venous catheter-related bacteremia associated with rifampicin-miconazole-impregnated catheters and standard catheters in patients with femoral and central jugular venous accesses.

METHODS

This was a cohort study, conducted in the 24-bed polyvalent medical-surgical intensive care unit of a university hospital. We included patients who were admitted to the intensive care unit from 1 June 2006 through 30 September 2007 and who underwent femoral or central jugular venous catheterization.

RESULTS

We inserted 184 femoral (73 rifampicin-miconazole-impregnated catheters and 111 standard catheters) and 241 central jugular venous catheters (114 rifampicin-miconazole-impregnated catheters and 127 standard catheters). We found a lower rate of central venous catheter-related bacteremia associated with rifampicin-miconazole-impregnated catheters than with standard catheters among patients with femoral access (0 vs. 8.62 cases per 1000 catheter-days; odds ratio, 0.13; 95% confidence interval, 0.00-0.86; P = .03) and among patients with central internal jugular access (0 vs. 4.93 cases per 1000 catheter-days; odds ratio, 0.13; 95% confidence interval, 0.00-0.93; P = .04).

CONCLUSIONS

Rifampicin-minonazole-impregnated catheters are associated with a statistically significant reduction in the incidence of catheter-related bacteremia in patients with short-term catheter use at the central jugular and femoral sites.

Anti-adherence activity and antimicrobial durability of anti-infective-coated catheters against multidrug-resistant bacteria

OBJECTIVES

To investigate the anti-adherence and antimicrobial durability of anti-infective catheters against multidrug-resistant (MDR) Staphylococcus aureus (resistant to vancomycin, rifampicin and methicillin) and MDR Gram-negative bacteria (Stenotrophomonas maltophilia, Acinetobacter baumannii/calcoaceticus and Enterobacter agglomerans) that are often associated with catheter-related bloodstream infections (CRBSIs).

METHODS

Catheters impregnated with minocycline and rifampicin (M/R) or with silver-platinum and carbon (SPC) or with chlorhexidine and silver sulfadiazine (CHX/SS) were compared with non-coated catheters. Adherence of organisms was tested by using an established biofilm colonization model. All isolates were rifampicin-resistant. Antimicrobial durability was tested by soaking 1 cm segments of the catheter in serum and determining zones of inhibition against the tested organisms at weekly intervals.

RESULTS

The M/R catheters showed significantly superior anti-adherence activity and more prolonged antimicrobial durability when compared with CHX/SS-central venous catheter (CVC), SPC-CVC and uncoated control catheters against MDR and vancomycin-resistant S. aureus (MDR VRSA) (all P values < or = 0.02), MDR S. maltophilia (all P values < 0.005) and MDR A. baumannii/calcoaceticus (all P values < 0.002), respectively. M/R-CVC and CHX/SS-CVC had comparable anti-adherence and antimicrobial durability against MDR E. agglomerans, and these two were superior to SPC-CVC and the uncoated control catheters (all P values < 0.001).

CONCLUSIONS

M/R-CVC demonstrated superior anti-adherence activity and more prolonged antimicrobial durability when compared with other approved anti-infective catheters against MDR VRSA and/or MDR Gram-negative bacteria that are often associated with CRBSIs. This finding could explain their efficacy and better performance in clinical studies.

Diagnosis and prevention of catheter-related infections

PURPOSE OF REVIEW

To highlight the major advances in diagnosing and preventing catheter-related infections published in research articles published between March 2004 and May 2007.

RECENT FINDINGS

The challenge remains to make the diagnosis of catheter-related infection with good accuracy without catheter removal. The differential time to obtain positive qualitative blood culture appeared to be the most accurate available technique. Many catheter-related bloodstream infections are preventable. Simple interventions are often useful and multimodal programs are very efficacious, particularly in the intensive care setting. For long-term catheter-related bloodstream infection prevention, patient education appeared promising. Interesting evidence suggested that anticoagulant, by decreasing the biofilm formation, could decrease the risk of infection. For short-term central venous catheter-related infections research is ongoing on antiseptic dressings. Antiseptic lock appeared promising for preventing long-term central venous catheter bloodstream infections.

SUMMARY

Nowadays, multimodal programs of catheter infection prevention are efficacious. Levels of catheter-related bloodstream infection of more than one or two per 1000 catheter-days are usually only found in the intensive care unit. It is a prerequisite to evaluate the cost-effectiveness of new techniques of prevention. As catheter-related bloodstream infections become rarer, strategies limiting unnecessary removal of catheters need to be developed and tested.

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.

Health technology assessment in critical care

BACKGROUND

Heath technology assessments (HTAs) evaluate the benefits and costs of devices for monitoring and therapy (and their associated requirements for human resources) which contribute to the high expense associated with ICU admission.

DISCUSSION

Given the limited resources available for health care and increasing demands, funds spent inefficiently or unnecessarily on technologies in the ICU may threaten the sustainability of the health care system or prevent other potentially cost-effective devices from being introduced into clinical care. We discuss the factors impeding the conducting of HTAs in the ICU and suggest strategies for change.

CONCLUSIONS

Despite the need for HTAs of ICU devices only few have been conducted. They should be undertaken more frequently, and their results used to influence clinical practice and hospital and regional-level policy decisions.

Prevention of primary bacteraemia

This overview provides information on recent advances in the prevention of primary bacteraemia, commonly defined as bloodstream infection without a documented source of infection, but including those resulting from an intravenous or arterial line infection. The potential to prevent community-acquired, primary bacteraemia is still limited and may be targeted mainly at vaccines for high-risk groups. In contrast, the prevention of catheter-related bacteraemia has seen substantial progress within the last 10 years. Consequently, intravascular device-related bacteraemia has become largely preventable under routine working conditions. Independent of the use of antibiotic-coated catheters, the implementation of clinical pathways and multimodal preventive strategies directed at several risk factors of catheter-related bacteraemia is a successful strategy to reduce this potentially life-threatening infection and deserves future health services research.

Prevention of catheter-related blood stream infection

PURPOSE OF REVIEW

Catheter-related blood stream infections are a morbid complication of central venous catheters. This review will highlight a comprehensive approach demonstrated to prevent catheter-related blood stream infections.

RECENT FINDINGS

Elements of prevention important to inserting a central venous catheter include proper hand hygiene, use of full barrier precautions, appropriate skin preparation with 2% chlorhexidine, and using the subclavian vein as the preferred anatomic site. Rigorous attention needs to be given to dressing care, and there should be daily assessment of the need for central venous catheters, with prompt removal as soon as is practicable. Healthcare workers should be educated routinely on methods to prevent catheter-related blood stream infections. If rates remain higher than benchmark levels despite proper bedside practice, antiseptic or antibiotic-impregnated catheters can also prevent infections effectively. A recent program utilizing these practices in 103 ICUs in Michigan resulted in a 66% decrease in infection rates.

SUMMARY

There is increasing recognition that a comprehensive strategy to prevent catheter-related blood stream infections can prevent most infections, if not all. This suggests that thousands of infections can potentially be averted if the simple practices outlined herein are followed.

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.

Rifampicin-impregnated central venous catheters: a meta-analysis of randomized controlled trials

BACKGROUND

The use of antimicrobial-impregnated central venous catheters (CVCs) for the prevention of CVC microbial colonization and catheter-related bloodstream infection (CRBSI) remains controversial.

METHODS

We performed a meta-analysis of randomized controlled trials (RCTs) evaluating CRBSI and colonization of CVCs impregnated with rifampicin-based antimicrobial combinations. Our main analysis compared the occurrence of CRBSI with rifampicin/minocycline-impregnated CVCs with that of non-rifampicin-impregnated CVCs. The PubMed and Cochrane Central Register of Controlled Trials databases were searched (until October 2006).

RESULTS

Eight RCTs were included in the analysis. The main analysis (seven RCTs) demonstrated that rifampicin/minocycline-impregnated CVCs were associated with fewer CRBSIs compared with catheters not impregnated with rifampicin/minocycline (OR 0.23, 95% CI 0.14-0.40). The same was true regarding colonization (OR 0.46, 95% CI 0.31-0.69). Further analysis, comparing rifampicin-based CVCs with non-rifampicin-impregnated CVCs, demonstrated superiority of rifampicin-based CVCs in reducing colonization (OR 0.38, 95% CI 0.24-0.62) and CRBSI (OR 0.24, 95% CI 0.14-0.40). Similar results, suggesting superiority of rifampicin/minocycline-impregnated CVCs, were noted in a subgroup analysis of colonization and CRBSIs in which rifampicin/minocycline-impregnated CVCs were compared with simple, non-tunnelled, non-antimicrobially impregnated CVCs, a subgroup analysis that was performed by excluding low quality RCTs, and a subgroup analysis for colonization comprising studies in which the sonication technique was used. No serious adverse events and no difference in mortality between the two treatment groups were reported. No clear conclusions can be made regarding the impact of the use of rifampicin/minocycline-impregnated CVCs on the development of antimicrobial resistance based on the available data.

CONCLUSIONS

The available evidence suggests that rifampicin/minocycline-impregnated CVCs are safe and effective in reducing the rate of catheter colonization and CRBSI. Further research should focus on the possible development of resistance and on pharmacoeconomic issues related to the use of rifampicin/minocycline-impregnated CVCs.