Central venous catheters are an important part of critical care but can lead to bloodstream infections in 5-20% of hospitalized patients. The most common causes are coagulase-negative staphylococci and S. aureus. Prevention strategies focus on catheter design, careful insertion and maintenance, and using antimicrobial coatings or locks. Treatment involves removing and replacing the catheter along with systemic antibiotics.

1. CENTRAL VENOUS CATHETER-RELATED
BLOODSTREAM INFECTIONS
DR KAMRAN AFZAL
DEPARTMENT OF PATHOLOGY

2. CENTRAL VENOUS CATHETER-RELATED
BLOODSTREAM INFECTIONS
 CVC an important part of critical care medicine
 CR-BSI occur in 5 – 20% of hospitalized catheterized
patients
Attributable mortality rate: 10 – 20%
More than 90% of nosocomial BSI are associated
with CVC

3. CENTRAL VENOUS CATHETERS (CVC)
 PERCUTANEOUS – NTCVC SHORT TERM – PICC
SUBCUTANEOUS – TCVC TOTALLY IMPLANTED – TID

4. USES
Fluids
Blood products
Drugs
Parenteral nutrition
Infusion therapy
Pressure monitoring

5. RISK FACTORS
Frequent manipulations
Prolonged use
Repeated use
Violation of asepsis
Site of insertion
Insertion / maintenance by
inexperienced staff
Immunocompromised state

6. ETIOLOGIC AGENTS
Coagulase negative Staphylococcus
Staphylococcus aureus
Enterococcus spp
Pseudomonas spp
Acinetobacter spp
Escherichia coli
Klebsiella spp
Enterobacter spp
Corynaebacterium spp
Candida spp

7. CASE DEFINITIONS- I
CATHETER CONTAMINATION
< 103 CFU / ml (catheter tip)
Organisms reach, adhere,
multiply
CATHETER COLONIZATION
> 103 CFU / ml (catheter tip)
Blood culture negative for
same organism / 24 hrs

8. CASE DEFINITIONS- II
LOCAL INFECTION
> 103 CFU / ml (catheter tip)
Local signs and symptoms
within 2 cm of skin
CATHETER-RELATED
BLOODSTREAM INFECTION
> 103 CFU / ml (catheter tip)
Blood culture positive for
same organism / 24 hrs
Defervescence on removal
of catheter

9. PATHOGENESIS- I
• Adherence of microorganisms
• Formation of thrombin biofilm

10. PATHOGENESIS- II
MATERIAL
Teflon, Polyurethane, Silicone
 ADHERENCE PROPERTIES
Coagulase negative Staphylococcus
Slime: glycocalyx formation on polymer surface
Staphylococcus aureus
Host protein: fibronectin, coagulase production
Candida albicans
Surface receptors: thrombin biofilm

11. PATHOGENESIS- III
ROUTES OF INFECTION SHORT TERM
Extra-luminal <14 days
Intra-luminal Skin microorganisms
Haematogenous Cutaneous tract
Extra-luminal colonization
Infusates
LONG TERM
>14 days
Contamination of catheter
hub
Intra-luminal colonization

12. COMPLICATIONS OF CVC
FAULTY INSERTION THROMBOSIS
Pneumothorax Local
Haemothorax CV thrombosis
Arterial puncture
Air embolism INFECTION
Thoracic duct laceration Exit site
Brachial plexus injury Bacteraemia
Catheter malposition Septicaemia
MECHANICAL METASTASIS
Kinking Osteomyelitis
Cracking Pneumonia
Displacement Endocarditis

13. LAB DIAGNOSIS
QUANTITATIVE CULTURE PAIRED QUANTITATIVE
Accurate CULTURE
High sensitivity and Accurate
specificity 10 : 1 CFU / ml
> 103 CFU / ml between CVC and
Sonication peripheral blood
Ultra-sonication
Vortex DIFFERENTIAL TIME TO
POSITIVITY
Surface and lumen
Cut off: 120 minutes
SEMI-QUANTITATIVE
CULTURE GRAM STAIN AND AOLC
Simplest and commonly Rapid
used Simple
> 15 CFU Inexpensive
External surface High sensitivity and specificity

14. SPECIMEN COLLECTION- I
INSERTION
Aseptic procedure
CVC: In OT under GA
CVP: In ward under LA
REMOVAL
Suspicion of infection
(local / systemic)
No longer required
Aseptic procedure
COLLECTION
Sterile container

15. SPECIMEN COLLECTION- II
BLOOD CULTURE
At the time of catheter
insertion and then at removal
Fever >1010 F, chills, shock
PUS / PUS SWAB
Site of insertion
Local signs and symptoms

16. BACTERIAL CULTURE
CATHETER TIP
Cleri’s quantitative culture method
Blood and MacConkey agar
at 370 C aerobically for 24 - 48 hrs
BLOOD
BHI broth at 370 C aerobically for
up to 7 days
Sub-culture on days 1, 2, 4 and 7
on Blood and MacConkey agar
PUS / PUS SWAB
Blood and MacConkey agar
at 370 C aerobically for 24 - 48 hrs

17. FUNGAL CULTURE
CATHETER TIP
Sabouraud’s agar at 220 C
aerobically for up to 14 days
BLOOD CULTURE
Trypticase soy broth at 220 C
aerobically for up to 14 days
PUS / PUS SWAB
Sabouraud’s agar at 220 C
aerobically for up to 14 days

18. IDENTIFICATION
BACTERIAL ISOLATES
Colony morphology
Gram’s stain
Biochemical tests
Serology
API galleries
FUNGAL ISOLATES
Colony morphology
Gram’s stain
Lactophenol blue stain
Biochemical tests
API Candida

19. ANTIMICROBIAL SUSCEPTIBILITY TESTING
BACTERIAL ISOLATES
Modified Kirby-Bauer
disk diffusion method
CLSI
FUNGAL ISOLATES
MICs by Etest

20. PREVENTION
APPROACH EFFECT
CATHETER DESIGN
• Smooth topography Discourages thrombus formation,
microbial adherence, colonization
• Antibiotic coating Reduces microbial adherence
CARE OF INSERTION SITE
• Skin preparation and antisepsis Reduces possibility of catheter
contamination
• Application of antimicrobials Reduces skin microbial load
(mupirocin) at insertion site
• Use of (silver-impregnated) Prevents migration of organisms
antimicrobial cuff at insertion site down the external surface of catheter
• Use of antibiotic-heparin flush soln Discourages fibrin collection / biofilm
• Regular use of antiseptics on hub Reduces hub contamination
• Use of prophylactic antibiotics Reduces catheter-related infections

21. TREATMENT
Glycopeptides with / without gram negative coverage
Substitution of catheter with / without replacing it at
an alternate site
Guide-wire exchange
Systemic antimicrobial therapy without removing
catheter
Antibiotic-lock technique
Antibiotic and heparin lock solution

22. INCIDENCE OF CR-BSI
INCIDENCE TYPE OF YEAR REFERENCE
CATHETER
16.8% CVC 2003 AFIP study
19.8% CVC / 1999 Souweine et al
Peripheral
17.6% CVC / 2000 Petrosillo et al
Peripheral
15.1% Peripheral 2001 Hafeez et al
12.0% CVC 2001 Nicastri et al
10.1% CVC / 2000 Kinkelstein et al
Peripheral
8.9% CVC 1999 Timsit et al
3.3% CVC 2000 Sherertz et al

23. CONCLUSIONS
• Central venous catheter is an important source of
bloodstream infection in catheterized patients
• A glycopeptide and a carbapenem, or pipracillin-
tazobactam, or cefoperazone-sulbactam are
recommended to be included in the empirical regimen
in high risk cases
• There is a need to implement more effective infection
control measures and more advanced technologies in
an effort to reduce this high incidence