> Home > Prevention & Intervention > Mythbusters

SEE IF YOU CAN TELL FACT FROM FICTION. From cost savings to Candida, Clinical Mythbusters tackles questions you face every day. To get Clinical Mythbusters FREE every month, sign up now!

 

 

 

 

<previous>  <next>

 

 

When comparing two or more antimicrobial catheters, there is a strong correlation between zone of inhibition size and effectiveness at preventing bloodstream infection.

 

False

 

The genesis of a catheter-related infection is a potential pathogen's adherence to the catheter. So the real test of an antimicrobial catheter's efficacy is whether—and for how long—the antimicrobial agents prevent pathogens from adhering, rather than the size of the zone of inhibition (ZOI) a particular catheter creates.

 

Case in point: In comparing antiseptics and antibiotics used in medical devices, Tambe, Sampath and Modak found that silver sulfadiazine/chlorhexidine catheters created a smaller ZOI against Staphylococcus epidermidis than antibiotic catheters. However, the silver sulfadiazine/chlorhexidine catheters prevented bacterial adherence to the catheter, whereas "... the antibiotic catheter showed adherence despite a larger zone size."(1) They concluded that "... the relatively smaller zones of inhibition with antiseptic catheters do not appear to be predictive of lack of efficacy."(1)

 

As an aside, S. epidermidis causes 37% of bloodstream infections, with a mortality rate of 21%. By comparison, Candida albicans is responsible for 8% of CRBSIs, yet it has a 40% mortality rate.(2,3) Considering the effectiveness of silver sulfadiazine/chlorhexidine against Pseudomonas aeruginosa and fungal organisms such as C. albicans,(4) and the limited documented evidence of antibiotic catheters' effectiveness against these organisms,(5,6) healthcare institutions should consider spectrum of activity when choosing and implementing infection-control tools.(3)

 

REFERENCES:

(1) Tambe, S.M., Sampath, L., Modak, S.M. "In vitro Evaluation of the Risk of Developing Bacterial Resistance to Antiseptics and Antibiotics Used in Medical Devices." The Journal of Antimicrobial Chemotherapy, Vol. 47, No. 5, 2001, pp. 589–598.

 

(2) O'Grady, N.P., Alexander, M., Dellinger, E.P., Gerberding, J.L., Heard, S.O., Maki, D.G., Masur, H., McCormick, R.D., Mermel, L.A., Pearson, M.L., Raad, I.I., Randolph, A., Weinstein, R.A. "Guidelines for the Prevention of Intravascular Catheter-Related Infections." Centers for Disease Control, August 9, 2002, Vol. 51, No. RR10, pp. 4–5.

 

(3) Wenzel, R.P., Edmond, M.B. "The Impact of Hospital-Acquired Bloodstream Infections." Emerging Infectious Diseases, March–April 2001, Vol. 7, No. 2. pp. 174–177.

 

(4) Data on file.

 

(5) Leon, C., Ruiz-Santana, S., Rello, J., et al. "Benefits of Minocycline and Rifampin-Impregnated Central Venous Catheters: A Prospective, Randomized, Double-Blind, Controlled, Multicenter Trial." Intensive Care Medicine, October 2004, Vol. 30, pp. 1891–1899.

 

(6) Wright, F., Heyland, D.K., Drover, J.W., McDonald, S., Zoutman, D. "Antibiotic-Coated Central Lines: Do They Work in the Critical Care Setting?" Clinical Intensive Care 2001, February 01, 2001, Vol. 12, Number 1, pp. 21–28.

 

 

See the full list of mythbusters

Learn what's true and false about catheters and sign up for
our free bulletin on catheters and related subjects

 



Institute of Healthcare Improvement
 5 million lives campaign

The 5 Million Lives Campaign is a voluntary initiative to protect patients from five million incidents of medical harm over the next two years (December 2006 – December 2008).

 

Center for Disease Control and Prevention (CDC)

Recommendations of CDC and the Healthcare Infection Control Practices Advisory Committee