Blood culture differential time to positivity enables safe catheter retention in suspected catheter-related bloodstream infection: a randomized controlled trial

Abstract

Objective: To evaluate the clinical usefulness and safety of the differential-time-to-positivity (DTP) method for managing the suspicion of catheter-related bloodstream infection (CR-BSI) in comparison with a standard method that includes catheter removal in critically ill patients.

Methods-design: A prospective randomized study was carried out.

Setting: A 16-bed clinical-surgical ICU (July 2007-February 2009).

Interventions: Patients were randomly assigned to one of two groups at the time CR-BSI was suspected. In the standard group, a standard strategy requiring catheter withdrawal was used to confirm or rule out CR-BSI. In the DTP group, DTP without catheter withdrawal was used to confirm or rule out CR-BSI.

Measurements: clinical and microbiological data, CR-BSI rates, unnecessary catheter removals, and complications due to new puncture or to delays in catheter removal.

Results: Twenty-six patients were analyzed in each group. In the standard group, 6 of 37 suspected episodes of CR-BSI were confirmed and 5 colonizations were diagnosed. In the DTP group, 5 of 26 suspected episodes of CR-BSI were confirmed and four colonizations were diagnosed. In the standard group, all catheters (58/58, 100%) were removed at the time CR-BSA was suspected, whereas in the DTP group, only 13 catheters (13/41, 32%) were removed at diagnosis, and 10 due to persistent septic signs (10/41, 24%). In cases of confirmed CR-BSI, there were no differences between the two groups in the evolution of inflammatory parameters during the 48hours following the suspicion of CR-BSI.

Conclusions: In critically ill patients with suspected CR-BSI, the DTP method makes it possible to keep the central venous catheter in place safely.

Keywords: Bacteriemia asociada a catéter; Catheter-related infections; Catéter venoso central; Central venous catheter; Critical care; Cuidados intensivos; Diagnosis; Diagnóstico.