Comparative Stability and Quality Assessment of Powder–Liquid Double-Chamber Bag Versus Traditional Meropenem Infusions: Implications for Critical Care and Individualized Dosing

Background: Maintaining therapeutic meropenem plasma concentrations requires prolonged infusion, but stability concerns exist between preparation and administration. This study compared the stability and operability of ready-to-use powder–liquid double-chamber bag (DCB) infusions versus traditional powder-for-injection (PFI) meropenem under clinical conditions. Methods: Infusions at clinically relevant concentrations were stored at 2–8 °C, 25 ± 5 °C, and 40 ± 2 °C for 12 h. Stability assessments included appearance, pH, osmolality, insoluble particle count, meropenem content (HPLC), and impurity A level. Results: DCBs demonstrated superior content uniformity, significantly fewer insoluble particles (p < 0.05), and greater operational simplicity compared to PFI. Refrigeration maintained meropenem content > 95% and effectively suppressed impurity formation for up to 12 h. However, at both room temperature and elevated temperature, impurity A exceeded pharmacopoeial limits within 2 h, particularly at higher concentrations. An innovative bedside solvent volume adjustment method enabled DCBs to deliver high-concentration infusions, facilitating individualized critical care dosing. Conclusions: Compared with traditional powder injection formulations, the Meropenem powder–liquid dual-chamber bag offers more convenient operation under routine preparation conditions and poses a lower risk of contamination during the preparation process. Its stability is more sensitive to storage temperature, requiring strict adherence to refrigeration conditions. When stored under standardized conditions, the dual-chamber bag can better ensure drug efficacy stability and medication safety, making it particularly suitable for clinical emergency use and standardized workflow management.