For long-term central lines (CL), the lumen is the major source of central line-associated
bloodstream infections (CLABSI). The current standard of care for maintaining
catheter patency includes
flushing the CL with saline or
heparin. Neither agent has any antimicrobial activity. Furthermore,
heparin may enhance staphylococcal biofilm formation. We evaluated the safety and efficacy of a novel nonantibiotic
catheter lock
solution for the prevention of CLABSI. Between November 2015 and February 2016, we enrolled 60 patients with
hematologic malignancies who had peripherally inserted central
catheters (PICC) to receive the study lock
solution. The study lock consisted of 15 or 30 μg/ml of
nitroglycerin in combination with 4%
sodium citrate and 22%
ethanol. Each lumen was locked for at least 2 h once daily prior to being flushed. After enrollment of 10 patients at the lower
nitroglycerin dose without evidence of toxicity, the dose was escalated to the higher dose (30 μg/ml). There were no serious related adverse events or episodes of
hypotension with lock administration. Two patients experienced mild transient adverse events (one
headache and one
rash) possibly related to the lock and that resolved without residual effect. The CLABSI rate was 0 on lock days versus 1.6/1,000
catheter days (CD) off lock prophylaxis, compared with a rate of 1.9/1,000 CD at the institution in the same patient population. In conclusion, the
nitroglycerin-based lock prophylaxis is safe and well tolerated. It may prevent CLABSI when given daily to
cancer patients. Large, prospective, randomized clinical trials are needed to validate these findings. (This study has been registered at ClinicalTrials.gov under identifier NCT02577718.).