CR-BSI

CATHTER RELATED BLOOD STREAM INFECTIONS (CR-BSI)

Dr. RAGHU PRAKASH REDDY

INTRODUCTION

INCIDENCE

• CRBSI are common,costly,and potenially lethal.• 80,000 CRBSI estimated per year in USA.• 28,000 deaths in ICU.• Cost per episode around 45,000$.• Total annual cost $2.3 billion annually.• According to CDC median rate of CRBSI in ICU

of all types ranges from 1.8 to 5.2 per 1000 catheter days

• Each year in U.S – 80,000 CR-BSI are estimated in ICU settings.

• Cost per episode-$45,000• Total annual cost-$2.3 billion• According to CDC,median rate of CR-BSI

in ICUs of all types ranges from 1.8 to 5.2 per 1000 catheter-days

Catheter-related bloodstream infections (CRBSI)

• Majority of cases associated with CVCs

• Avg. rate of 5.3 CRBSI per 1,000 catheter days¹

• Estimated 250,000 cases annually²– ICU = 80,000 cases– Costs = $25,000/case– Annual cost = $6.25 billion

• Mortality ranges from 12%-35%

Pathogen1986 -1989 (%)³

1992 -1999 (%)4

CoNS 27 37

S. aureus 16 13

Enterococcus 8 13

GNR 19 14

Candida sp. 8 8

¹CDC. Am. J. Infect. Control. 1998;26:522-33. ³Schaberg DR, et al. Am. J. Med. 1991;91(3B):S72-75. ²Kluger Dm, et al. 39th ICAAC. [Abstract 1913]. 1999:514. 4CDC. Am. J. Infect. Control. 1999;27:520-32.

RISK FACTORS

• Granulocytopenia• Immunosuppressive chemotherapy• Loss of skin integrity(burns, psoriasis)• Severity of underlying illness• Active infection at other site• Alteration in patients cutaneous microflora.

Failure of health care provider to wash hands• Contaminated ointment or cream

Cont…

• Number of lumens • Catheter function/use • Catheter management strategies • Types of catheter (plastic>steel) • Location of catheter (central>peripheral;

jugular>femoral>subclavian; lower extremity > upper extremity )

• Type of placement • Duration of placement • Emergent > elective• Skill of venipuncturist • Type of catheter

• Microorganisms Involved• Staphylococcus aureus• Coagulase negative Staphylococci• Enterococus spp.• Serratia marcscens• Candida• Pseudomonas aeroginosa• Klebsiella spp.• Enterobacter spp.• Citrobacter freundii• Corynebacterium • Burkholveria cepacia

• BIOFILMS• Definition*: A microbial derived sessile

community characterized by cells that are irreversibly attached to a substratum or interface to each other, are embedded in a matrix of extracellular polymeric substances that they have produced, and exhibit an altered phenotype with respect to growth rate and gene transcription.

• Donlan RM, Costerton JW. Clin Microbiol Rev 2002;15:167-193

• BIOFILMS• Enhanced microbial survival (impairs host defenses)• Impairs antimicrobial activity• Common microbes• Staphylococcus aureus, coagulase negative• staphylococci, Enterococcus spp., Streptococcus• viridans• E. coli, Klebsiella pneumoniae, Proteus mirabilis,• Pseudomonas aeruginosa• Candida albicans

• FORMATION OF BIOFILMS• Deposition of a conditioning film produced by the

host to the foreign body• Attachment of microorganisms• Microbial adhesion and anchorage to the surface

by exopolymer production• Growth, multiplication and dissemination of

microbes.

• Tenke P, et al. World J Urol 2006;24:13-20

CR-BSI :def by NNISS

• Presence of recognized pathogen cultured from one or more blood culture

• and• Organisms cultured from blood not related to

infection at another site OR fever (temperature >38 c ), Chills, Hypotension AND Cont…

• Signs and symptoms and positive results not related to

infection at another site AND• Presence of at least one of the following : -Common skin contaminant (e.g., diphtheroids, bacillus

species, propionibacterium species, coagulase negative staphylococci or micrococci) cultured from two or more blood samples drawn on separate occasions

-Common skin contaminant cultured from at least one blood culture in a sample from a patient with the intravascular catheter

-Positive antigen test on blood (e.g., Haemophilus influenzae, Streptococcus, Pneumoniae, Neisseria meningitidis, or group B streptococcus)

• CATHETER CULTURES

. The CDC recommends the use of either quantitative or semi quantitative catheter segment culture techniques.

- The semiquantitative roll-plate method is most commonly used because of its simplicity. A 5-cm catheter tip segment is rolled over a blood agar plate, and colony forming units are counted after incubation overnight. The clinical usefulness of semiquantitative catheter cultures is questioned because it does not detect intraluminal colonization, risking a false-negative result.

- Quantitative culture, accomplished by vorted, sonication, or centrifugation of the catheter segment in broth followed by serial dilution and plating on blood agar, is the most reliable catheter culture technique because it harvests most of the adherent biofilm bacteria from both the internal and external catheter surfaes.

A yield of >/=103cfu/catheter segment by quantitative method, or a count of >/=15 cfu/catheter segment by semiquantitative method with accompanying signs if local or systemic infection indicates CRBSI

• BLOOD CULTURES

. The CDC recommends one of 2 blood culture techniques for diagnosing CRBSI;

-Paired quantitative blood cultures ( >/=5:1or 100 cfu/ml from single quantitative

cultures)

-Paired qualitative blood cultures

SVIMS EXPERIENCE

RETROSPECTIVE STUDY FROM 1-8-06 - 1-6-07

• Number of samples studied -60• Stap.aureus-11• Coagulase negative staph-7• Pseudomonas -6• Klebsiella-3• Enterobacter-3• E.coli-2• Providencia-2• Proteus-1• Candida-1• BHS -1• NFGNB-1• Combined infections -13 (GNB)

CONCLUSIONS

• Multiple studies have evaluated the efficacy of impregnated catheters for the prevention of CRBSIs• – 2nd generation catheters superior to 1st generation• catheters• – Adverse events rare• – Induction of resistance not reported• – Impregnated CVCs have reduced rates of• colonization and likely lead to a reduction in CR-BSIs• • Consider use of impregnated central venous• catheters as part of a multi-faceted approach to• reducing CR-BSI

• MECHANISMS OF ACTION OF• ANTIMICROBIALS COMMONLY USED TO• IMPREGNATE CATHETERS• Chlorhexidine• – Bactericidal; precipitates cytoplasmic contents of• the cell• Silver-sulfadiazine• – Bactericidal; disrupts cell wall• Minocycline• – Bacteristatic; blocks the binding aminoacyl-tRNA• mRNA-ribosome complex• Rifampin• – Bacteriostatic; inhibits DNA-dependent, RNApolymerase

INTERVENTIONS TO PREVENT COMPLICATIONS• Type of complication and interventions:• INFECTIOUS Use antimicrobial-impregnated catheters: The use of antimicrobial impregnated catheters reduces the risk of catheter

related bloodstream infections and reduces costs when the rate of catheter-related bloodstream infection>2 % Insert catheters at the subclavian venous site:

The risk of catheter related infection is lower with subclavian catheterization than with internal jugular or femoral catheterization

Use maximal sterile barrier precautions during catheter insertion: Use of a mask, cap, sterile gown, sterile gloves, and large sterile drape

reduces the rate of infections and reduces costs Avoid the use of antibiotic ointments: The application of antibiotic ointments increases the rate of colonization by

fungi,, promotes the development of antibiotic resistant bacteria,, and has not been shown to affect the risk of catheter related bloodstream infections.

• Disinfect catheter hubs: Catheter hubs are common sites of catheter contamination - Do not schedule routine catheter changes Scheduled, routine replacement of central venous catheters at a

new site does not reduce the risk of catheter related bloodstream infection, scheduled, routine exchange of catheters over a guide wire is associated with a trend toward increased catheter-related infections

- Remove catheters when they are no longer needed: The probability of colonization and catheter-related bloodstream

infection increases over time -

Summary• Biofilm formation on intravascular catheters creates an a

ABL Technique antibiotic resistant environment– 100 -1000 times MIC required

• ABL therapy has a role in prevention and should be considered as adjuvant therapy in treatment– Catheter removal not feasible

• Continued research needed to identify potential ABL solutions as their use continues to expand– EtOH lock solutions– EDTA based solutions

ABL Technique

• Heparin requirements– Dialysis catheters

• 2,500 – 5,000 units/mL in lock solution– Other CVCs

• 10 – 100 units/mL in lock solution

• Typical port requires approximately 3 mL of fill volume– WFUBMC – send 5 mL syringes (with 3 mL of

lock solution) per port

•

• High antibiotic concentrations required• Antibiotic-anticoagulant combinations