Long-term stability of 10 mg/mL dobutamine injectable solutions in 5% dextrose and normal saline solution stored in polypropylene syringes and cyclic-oleofin-copolymer vials.

Objective: Dobutamine is an inotropic agent given to patients with low cardiac output or undergoing cardiac surgery in intensive care units. Routine clinical care protocols recommend a target dilution concentration of 10 mg/mL dobutamine from the 250 mg/20 mL commercial solution.This study aimed to assess the 1-year stability of ready-to-use 10 mg/mL diluted dobutamine solutions. Two types of 50 mL conditioning, polypropylene (PP) syringes or cyclic-oleofin-copolymer (COC) vials and two diluents (5% dextrose (D5W) and normal saline (NS)) were tested.

Methods: Reversed-phase liquid chromatography coupled with an ultraviolet detection stability-indicating method was developed for dobutamine and validated according to selectivity, linearity, sensitivity, accuracy and precision. Chemical stability was considered to have been maintained if the measured concentrations were >90% of the initial concentration with no colour change. Physical stability was assessed through sterility tests, pH and osmolality monitoring, and subvisible particle counting. Containers were stored at -20±5°C, +5±3°C and +25±2°C with 60%±5% relative humidity in a dark, closed environment.

Results: According to this study, the physicochemical stability of 10 mg/mL dobutamine solutions prepared with D5W or NS is constant throughout a 365-day period when stored in COC vials, at all the aforementioned temperatures, whereas solutions in PP syringes required a refrigerated temperature and should not be administered after 21 days or 3 months when prepared with D5W or NS, respectively, or after 1 month at ambient temperature whatever the diluent.

Conclusion: Our results argue in favour of adopting the compounding of ready-to-use 10 mg/mL dobutamine solutions in COC vials in centralised intravenous additive services.