1. Typically we begin to suspect that the patient may have a catheter related
blood stream infection when there is fever that has been unaccounted for and
that they may have had a catheter in place for some time or it may be unclear
whether pt may have a CRBSI and thus it is left in. Therefore, will first talk
about the diagnosis of catheter related blood stream infection through blood
cultures as opposed to diagnosing after the catheter has been pulled and that
the tip is cultured.

2. Some important points about diagnosis of CRBSI:
-Clinical findings are unreliable  poor sensitivity and specificity
-Most sensitive is fever, but has poor specificity
-Inflammation or pururlence around insertion site has greater specificity but
poor sensitivity
-In general blood cultures positive for the following species should make you
more suspicious of CRBSI:
- S. aureus
- Coag-neg staph
- Candida species
- Recently inserted catheter (i.e. one that had ben indwelling < 14
days) is commonly colonized from skin microorganisms along the

3. Definition of positive CRBSI via Differential time to positivity is comparing the
catheter to the peripheral vein to see which sample grows out first.
-Monitoring for growth is based on radiometric methods
-So the theory is that the greater the inoculum of microbes inoculated into
blood cultures bottles, the shorter the incubation required to detect microbial
growth, one would expect the catheter to have the greater inoculum.
-85-89% sensitivity and 81-83% specificity in meta-analysis of 8 studies

4. Obtain blood culture from peripheral vein and from the central line.
If the blood culture from the central line becomes positive at least two hours
before that of the peripheral line, then diagnosis of CRBSI.
How do you proceed from here if positive CRBSI?

5. Other treatment modalities not discussed:
Salvage
Exchange
Antibiotic lock therapy

6. Main point of this slide is to say that these are “COMPLICATED” infection
scenarios that require catheter removal. You’ll see this reiterated in the flow
diagram towards the end of this presentation. Anything that falls under
“complicated” means you need to remove the catheter.

7. Main point of this slide is to say that these are “COMPLICATED” infection
scenarios that require catheter removal. You’ll see this reiterated in the flow
diagram towards the end of this presentation. Anything that falls under
“complicated” means you need to remove the catheter.