Rabbit Hole: Citrate

Recently, trisodium citrate has also been used as a locking agent in vascath and haemodialysis lines instead of heparin due to its lower risk of systemic anticoagulation.[8]

https://en.wikipedia.org/wiki/Trisodium_citrate

Locking is defined as the injection of a limited volume of a liquid following the catheter flush, for the period of time when the catheter is not used, to prevent intraluminal clot formation and/or catheter colonization.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4446496/

some are even approved for the high pressure of CT-power injection. Also, almost all totally implantable venous access devices (TIVADs) or so called ports, in the marketplace, are power-injectable nowadays [9].

My god. Nurses must have so much expertise.

Power Injectors have embedded safety features which automatically reduce the contrast administration flow rate when they reach the 300 psi threshold.
https://www.med.unc.edu/pediatrics/cccp/wp-content/uploads/sites/1156/2025/08/CT-PIV-Guidelines-06Aug25.pdf

  • Sepsis: Using aseptic technique during loading/emptying the left over contrast and/or saline, preferred use of pre-filled syringes, and hand hygiene can prevent sepsis. In a study, double-syringe injectors used with disposable or prefilled contrast agent syringes ensured hygienic conditions in routine clinical practice. The organisms evaluated in this study were coagulase-negative staphylococci, micrococcus, and bacillus species.[22]

Moreover it was found that antibiotic treatment, similar to heparin, can stimulate biofilm adherence to the catheter surface [39, 79]. Therefore there is an urgent need for alternative nonantibiotic locks and nonheparin anticoagulants.

Nonantibiotic locks or antiseptics kill bacteria through physical effects rather than specific biochemical pathways and may not induce microbial resistance [80]. Donlan described different approaches to the control of biofilms on intravascular catheters with chelating agents, ethanol, and taurolidine [73]. Chelating agents have the potential to remove established biofilm (bacteria and fungi). Sodium citrate and ethylenediaminetetraacetic acid (EDTA) are chelating agents. EDTA is used alone or in combinations with antibiotics [80, 81].

One newly developed locking solution has reduced the ethanol concentration in the locking solution to 20% in combination with 0.01% glyceryl trinitrate and 7% citrate. This lock showed promising results in eradicating biofilm in an in vitro test [86].

Taurolidine, a derivative of the amino acid taurine, is an antimicrobial agent showing a broad spectrum of antimicrobial activity against both bacteria and fungi [87, 88]. A meta-analysis of 6 small studies in patients with different catheter types and taurolidine concentrations suggest that taurolidine as locking solution reduces the CRBSI incidence without obvious adverse effects and bacterial resistance [89]. Abnormal taste sensations were reported in two studies [90, 91].

https://pmc.ncbi.nlm.nih.gov/articles/PMC4446496/

We found that 12.5× diluted solutions of all taurolidine containing formulations completely prevented growth of Escherichia coli, Staphylococcus aureus and Candida glabrata. Growth of these microbes was detected earlier in 1.34% taurolidine–citrate(–heparin) than in 2% taurolidine, while citrate and heparin did not inhibit growth of clinical isolates compared to PBS. No differences in biofilm formation were found between taurolidine containing solutions.
https://www.clinicalnutritionjournal.com/article/S0261-5614(14)00131-9/abstract

Neat!