Creating an evidence-based economic model for prefilled parenteral medication delivery in the hospital setting.

Objectives: Prefilled syringes (PFS) may offer clinical and economic advantages over conventional parenteral medication delivery methods (vials and ampoules). The benefits of converting from vials and ampoules to PFS have been explained in previous drug-specific economic models; however, these models have limited generalisability to different drugs, healthcare settings and other countries. Our study aims to (1) present a comprehensive economic model to assess the impact of switching from vials to PFS delivery; and (2) illustrate through two case studies the model's utility by highlighting important features of shifting from vials to PFS.

Methods: The economic model estimates the potential benefit of switching to PFS associated with four key outcomes: preventable adverse drug events (pADE), preparation time, unused drugs, and cost of supplies. Model reference values were derived from existing peer-reviewed literature sources. The user inputs specific information related to the department, drug, and dose of interest and can change reference values. Two hypothetical case studies are presented to showcase model utility. The first concerns a cardiac intensive care unit in the United Kingdom administering 30 doses of 1 mg/10 mL atropine/day. The second concerns a coronavirus (COVID-19) intensive care unit in France that administers 30 doses of 10 mg/25 mL ephedrine/day.

Results: Total cost savings per hospital per year, associated with reductions in pADEs, unused drugs, drug cost and cost of supplies were £34 829 for the atropine example and €104 570 for the ephedrine example. Annual preparation time decreased by 371 and 234 hours in the atropine and ephedrine examples, respectively.

Conclusions: The model provides a generalisable framework with customisable inputs, giving hospitals a comprehensive view of the clinical and economic value of adopting PFS. Despite increased costs per dose with PFS, the hypothetical case studies showed notable reductions in medication preparation time and a net budget savings owing to fewer pADEs and reduced drug wastage.