Lean and Green Hand Surgery: Evaluating the Sterility of Stored Corticosteroid Injection Preparations Using...

Corticosteroid injections are commonly performed in hand surgery and are often prepared in advance to improve efficiency. Despite aseptic preparation, unused syringes are routinely discarded due to concerns about microbiologic contamination, resulting in substantial avoidable waste. We conducted a controlled laboratory study simulating outpatient injection workflows to assess the sterility of stored corticosteroid-lidocaine injections using next-generation sequencing (NGS).

Sterile corticosteroid-lidocaine injections were prepared under aseptic conditions using sterile 3 mL Luer-lock syringes, 0.5 mL of 1% lidocaine, and 3 mg of triamcinolone acetonide (20 mg/mL), drawn with an 18-gauge needle and capped with a sterile 25-gauge needle. Syringes were labeled and stored at room temperature in a closed cabinet away from light and temperature fluctuation. The primary endpoint was the detection of bacterial DNA by NGS on either the 25-gauge needle or the fluid in the syringe. Samples were analyzed at 1 day, 3 days, 1 week, and 2 weeks postpreparation.

Forty experimental samples and 8 positive controls were analyzed. Of the experimental samples, 39 (97.5%) tested negative for bacterial DNA, including all 20 needle samples and 19 of 20 fluid samples. One fluid sample from the 1-week group tested positive for a Streptococcus species. All positive controls from the 1-day, 3-day, and 1-week groups demonstrated polymicrobial contamination.

Predrawn corticosteroid injections prepared under aseptic conditions demonstrated a low contamination rate over 2 weeks. These findings support extending injection use beyond same-day administration and provide an opportunity to reduce waste, lower costs, and advance sustainability in hand surgery.