Vancomycin and ceftazidime bioactivities persist for at least 2 weeks in the lumen in ports: simplifying treatment of port-associated bloodstream infections by using the antibiotic lock technique.

The residual antibiotic concentration of vancomycin (2 mg/ml)- or ceftazidime (2 mg/ml)-heparin solutions instilled in ports in pediatric hematology-oncology patients 1 to 34 days earlier was measured. Antibiotic concentrations of > or = 100 microg of either antibiotic per ml persisted for at least 21 days. For treatment of lumenal port infections, antibiotic-heparin dwell times of > or = 2 weeks may be appropriate.