In this episode, I’ll discuss time to positivity as a predictor of catheter-related bacteremia and mortality in adults with Pseudomonas aeruginosa bloodstream infection.
Two metrics are emerging as predictors of catheter-related infection with Pseudomonas as well as mortality risk:
1. Time to positivity, which is the time from when culture incubation starts to when growth is detected by automated systems.
2. Differential time to positivity, which is the difference in the time between when the catheter culture becomes positive and the time a simultaneously collected venipuncture culture becomes positive.
A group of authors recently published in the journal Critical Care a retrospective observational study that sought to identify the best cutoff times for time to positivity and differential time to positivity to allow clinicians to identify patients with catheter-related bacteremia and those at highest risk of mortality.
Over 1100 patients with time to positivity data were analyzed as were over 350 patients with differential time to positivity data.
Both a time to positivity less than 13 hours, and a differential time to positivity more than 2 hours were independently associated with catheter-related pseudomonas bacteremia.
Furthermore a time to positivity less than 14 hours was associated with increased mortality for patients who did not have adequate source control within 48 hours, and a time to positivity less than 16 hours was associated with an increased risk of mortality even with adequate source control. The odds ratio for mortality increased from 1.6 to 3.8 if empiric antibiotic therapy was not active.
Pharmacists can use this information to identify patients at highest risk of mortality from Pseudomonas catheter-related infection and take that information into account when evaluating whether the intensity of a patient’s antibiotic regimen is appropriate.
To get access to my free download area with 20 different resources to help hospital pharmacists go to pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.
Leave a Reply