Indwelling catheters and Hemodialysis Ports - Infections

11/10/2003

Question: What are useful techniques for prevention or detection of infections related to indwelling catheters and/or hemodialysis ports?

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Unique Identifier:12517018

Authors: Walder B. Pittet D. Tramer MR.

Institution: Division of Surgical Intensive Care, University of Geneva Hospitals, Geneva, Switzerland.

Title: 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.

Source: Infection Control & Hospital Epidemiology. 23(12):748-56, 2002 Dec.

Abstract: 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. CAS Registry/EC Number 0 (Anti-Infective Agents). 0 (Coated Materials, Biocompatible).

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Unique Identifier:10923768

Authors: Blot F. Nitenberg G. Brun-Buisson C.

Institution: Service de Reanimation Medicale, Hopital Henri Mondor, Creteil, France. blot@igr.fr

Title: New tools in diagnosing catheter-related infections. [Review] [37 refs]

Source: Supportive Care in Cancer. 8(4):287-92, 2000 Jul.

Abstract: Clinical criteria alone are insufficient to allow a diagnosis of intravascular catheter-related sepsis (CRS). A definite diagnosis of CRS usually requires removal of the catheter for quantitative catheter tip culture. However, only about 15-25% of central venous catheters (CVC) removed because infection is suspected actually prove to be infected, and the diagnosis is always retrospective. Other diagnostic tests, such as differential quantitative blood cultures from samples taken simultaneously from the catheter and a peripheral vein, have been proposed to avoid unjustified removal of the catheter and the potential risks associated with the placement of a new catheter at a new site: a central-to-peripheral blood culture colony count ratio of 5:1 to 10:1 is considered indicative of CRS. Despite its high specificity, the latter diagnostic technique is not routinely used in clinical practice because of its complexity and cost. The measurement of the differential time to positivity between hub blood (taken from the catheter port) and peripheral blood cultures might be a reliable tool facilitating the diagnosis of CRS in situ. In an in vitro study, we found a strong relationship between the inoculum size of various microorganisms and the time to positivity of cultures. When the times to positivity of cultures of blood taken simultaneously from central and peripheral veins in patients with and without CRS were examined, we found that earlier positivity of central vs peripheral vein blood cultures was highly correlated with CRS. Using a cut-off value of +120 min, the "differential time to positivity" of the paired blood samples, defined as time to positivity of the peripheral blood minus that of the hub blood culture, had 91% specificity and 94% sensitivity for the diagnosis of CRS. This method may be coupled with other techniques that have high negative predictive value, such as skin cultures at the catheter exit site. This diagnostic test can be proposed for routine clinical practice in most hospitals using automatic devices for blood cultures positivity detection. Endoluminal brushing of the catheter is considered sensitive and specific for the diagnosis of CRS, but the risk of embolisation or subsequent bacteraemia should be considered. Gram staining and the acridine-orange leucocyte cytospin test on through-catheter blood culture have been proposed for rapid diagnosis of CRS without catheter removal. The technique, which requires 100 microl catheter blood and the use of light and ultraviolet microscopy, is considered simple, rapid (30 min) and inexpensive. In conclusion, diagnostic tools such as paired blood cultures or Gram staining and the acridine-orange leucocyte cytospin test should allow a diagnosis of CRS without catheter removal in cancer patients. [References: 37]

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Unique Identifier:10204125

Authors: Peacock SJ. Curtis N. Berendt AR. Bowler IC. Winearls CG. Maxwell P.

Institution: Nuffield Department of Medicine, John Radcliffe, Oxford Radcliffe Hospital NHS Trust, Headington, UK.

Title: Outcome following haemodialysis catheter-related Staphylococcus aureus bacteraemia.

Source: Journal of Hospital Infection. 41(3):223-8, 1999 Mar.

Abstract: Staphylococcus aureus is a frequent cause of haemodialysis access-related bacteraemia. The propensity for this organism to seed from the bloodstream to distant sites is well recognized, but the rate at which this occurs is poorly defined in patients with removable haemodialysis catheters. This retrospective study identified 47 patients with 50 episodes of S. aureus haemodialysis catheter-related bacteraemia between August 1993 and December 1995. Adverse events were recorded until February 1996. Thirty of 50 episodes (60%) were apparently uncomplicated. Bacterial seeding to heart valves or distant sites was documented in eight episodes (16%), of which six occurred during antibiotic therapy. A further 12 patients had persistent bacteraemia in the absence of a defined focus of infection, the last positive blood culture ranging from 2-19 days (mean 6.6, median 5) after removal of the haemodialysis catheter and commencing appropriate antibiotic treatment. The serious nature of this infection confirms the need for prevention, together with effective strategies for investigation and treatment in this patient population. CAS Registry/EC Number 0 (Anti-Infective Agents).

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Unique Identifier:9481730

Authors: Nielsen J. Kolmos HJ. Espersen F.

Institution: Department of Nephrology, Hvidovre Hospital, Denmark.

Title: Staphylococcus aureus bacteraemia among patients undergoing dialysis--focus on dialysis catheter-related cases.

Source: Nephrology Dialysis Transplantation. 13(1):139-45, 1998 Jan.

Abstract: BACKGROUND: Central venous catheter-related infections are the most common cause of nosocomial S. aureus bacteraemia in Denmark. Central venous catheters are often used for dialysis, and patients on dialysis often run into staphylococcal infections. The purpose of this study was to investigate S. aureus bacteraemia among dialysis patients, especially those related to dialysis catheters. METHODS: This was a retrospective study of 14,387 consecutive S. aureus bacteraemia cases during the period 1976-93, of which 793 cases occurred among dialysis patients. By reviewing the case records, 65 dialysis catheter-related cases were described more thoroughly. RESULTS: The number of S. aureus bacteraemia cases among dialysis patients as a proportion of all cases in Denmark has increased from 5.2 to 14.7% during the study period, but the annual incidence among these patients has been almost stable during the period (median 5.7% (3.2-9.0%)). Patients on dialysis had a lower mortality than other patients with S. aureus bacteraemia (18.9 vs 29.0%), but a four times higher mortality from central venous catheter-related S. aureus bacteraemia (5.3 vs 1.3%, P < 0.001). The mortality from dialysis catheter-related S. aureus bacteraemia was correlated with greater age (median 71 years (57-73) vs median 56.5 years (15-76), P < 0.01) and with septic shock (55.5 vs 7.1%, P < 0.05). Patients on dialysis had a lower frequency of S. aureus endocarditis (3.3 vs 5.4%, P < 0.01) and of S. aureus bone and joint infections (3.3 vs 8.2%, P < 0.001) than other patients. Patients undergoing dialysis had a later onset of catheter-related S. aureus bacteraemia than other patients (median 15 days (1-145) vs 5 days (1-134), P < 0.05). CONCLUSIONS: Patients on dialysis are at a high risk of S. aureus bacteraemia and they have a four times higher mortality from central venous catheter-related S. aureus bacteraemia than other patients. There is need for prospective studies in which patients as well as catheters are followed more thoroughly to study the pathogenesis of dialysis catheter-related infections.