Antibiotic Lock Technique: Review of the Literature

Megan B. Bestul, PharmD; Heather L. VandenBussche, PharmD


Pharmacotherapy. 2005;25(2):211-227. 

In This Article


The antibiotic lock technique provides an alternative method to treat catheter-related sepsis or colonization, without the administration of systemic antibiotics or removal of the indwelling vascular device. It may also be useful in pre-venting CVC infection in certain patient populations, although development of resistance remains a concern with daily use of these solutions; however, the concern for resistance may be less with antibiotic lock technique than with systemic antibiotics and possibly flush solutions. Many antimicrobial combinations have been evaluated for stability (with or without heparin) and effectiveness for prevention and treatment of CVC infection. To prevent catheter-related sepsis, evidence supports the use of vancomycin 25 µg/ml in combination with heparin 9.75 U/ml to prevent gram-positive infections, with the possible addition of cipro-floxacin 2 µg/ml to prevent gram-negative infections when such therapy is considered appropriate based on patient characteristics. Preventive therapy may involve daily flush solu-tions or use of 1-hour dwell times every 1-2 days.

Use of antibiotic lock solutions to treat catheter-related sepsis remains controversial, although evidence is mounting that antibiotic lock technique may be used successfully to avoid catheter removal in certain patients. High intraluminal antibiotic concentrations may be needed, particularly if biofilm and fibrous material are present, in order to achieve bacterial eradication. Multiple antibiotic combinations with heparin have been studied and are stable for at least 12-24 hours. The antibiotic lock technique is well tolerated and generally effective in treating CVC-related infections that do not involve soft tissue at the insertion or tunnel site or that are not fungal in origin. Catheter clearance may be achieved after 1-2 weeks of antibiotic lock therapy alone or in combination with systemic antibiotics. The frequency of antibiotic locks and appropriate dwell time are not well established and must be individualized based on drug stability and frequency of intravenous drugs or fluids that are infused with use of the infected line. Large, prospective, randomized trials are needed to determine the most appropriate concentration of antibiotics, duration of therapy, and role of concomitant systemic antibiotics with antibiotic lock therapy for catheter-related sepsis.