Objectives To evaluate the stability of solutions of 6 mg/mL, 8 mg/mL and 12 mg/mL meropenem in 0.9% NaCl in a polyolefin container (Viaflo), at room temperature, with a view to allowing extended or continuous perfusion in clinical practice.

Methods Meropenem was assayed using high-performance liquid chromatography. The technique was validated according to the criteria of the European Medicines Agency. Meropenem stability was evaluated for three different concentrations (6 mg/mL, 8 mg/mL and 12 mg/mL) at room temperature and during 48 h. The pH of the solution and its organoleptic properties were also evaluated.

Results The analytical technique abided with the specifications of the European Medicines Agency. The maximum accuracy and precision were 10% and 7.9%, respectively. The limit of detection was 0.000185 mg/mL and the limit of quantification 0.000562 mg/mL. The t90 for the dilution of 6 mg/mL of meropenem was 18 h (95% CI 14 h to 22 h), while the values for the 8 mg/mL and 12 mg/L concentrations were respectively 22 h (95% CI 19 to 32 h) and 17 h (95% CI 13 h to 21 h). The differences were not statistically significant (p<0.05). No variations in pH were seen.

Conclusions The results confirm the stability of the solutions of 6 mg/mL, 8 mg/mL and 12 mg/mL meropenem in 0.9% NaCl stored in a polyolefin container at 25°C for at least 12 h, thereby allowing their use as an extended or continuous perfusion.