Clinical outcomes of antimicrobial lock solutions used in a treatment modality: a retrospective case series analysis

P Brandon Bookstaver¹, Katherine R Gerrald², Robert R Moran³

¹South Carolina College of Pharmacy, ³Health Science Research Core, University of South Carolina, Columbia, SC, USA; ²University of North Carolina Hospitals, Chapel Hill, NC, USA

Background: Antimicrobial lock therapy (ALT) may be considered as adjunctive therapy in the treatment of catheter-related bloodstream infections (CRBSI) when catheter removal is not a favorable option.

Objective: To evaluate the outcomes associated with ALT as adjunctive treatment of CRBSI.

Methods: This was a 24-month retrospective case series analysis evaluating patients treated for more than 24 hours with ALT. The primary outcome was blood culture sterilization for 30 days posttherapy. The impact of ALT duration and time to initiation on central venous catheter (CVC) salvage were evaluated. Logistic regression modeled the association between ALT and sterilization rates, with a prespecified level of significance (α) of 0.1.

Results: Twenty-six cases were included in data analysis. Patients included ranged from 5 months to 82 years of age; 77% of patients were receiving total parenteral nutrition or chemotherapy. The majority of patients received vancomycin, daptomycin, or gentamicin combined with heparin in a lock solution. Blood culture sterilization was achieved in 69.2% of cases, and sterilization plus CVC retention was achieved in 11 cases (42.3%). Longer durations of ALT (≥9 days) were significantly correlated with blood culture sterilization (odds ratio = 1.367, P = 0.077).

Conclusion: ALT used as an adjunct to systemic therapy for adequate duration in CRBSI can achieve CVC sterilization and retainment without subsequent infectious complications.

Keywords: antimicrobial lock therapy, central venous catheter, bacteremia, central lineassociated bloodstream infection