Stability of Dexmedetomidine in Polyvinyl Chloride Bags Containing 0.9% Sodium Chloride Intended for Subcutaneous Infusions.

Dexmedetomidine is a sedative medication with co-analgesic effects that has been used primarily in critical care and anesthesia as a continuous intravenous infusion. Its utility in the treatment of refractory agitated delirium is being investigated in other settings including palliative care, but continuous intravenous infusions are not always feasible during end-of-life care. Subcutaneous infusions are more commonly used in this setting, but smaller volumes and higher concentrations are typically required. Investigations into stability at these higher concentrations are required to address preparation and administration feasibility issues. The objective of this research was to study the chemical stability of high-concentration dexmedetomidine 20 mcg/mL prepared in polyvinyl chloride bags with 0.9% sodium chloride and storage up to 9 days under refrigeration and room temperature conditions. A total of four solutions of dexmedetomidine 20 mcg/mL in 0.9% sodium chloride were prepared in polyvinyl chloride bags under sterile conditions. Two bags were stored under refrigeration and two bags at room temperature. Duplicate samples were withdrawn from each bag at hours 0, 24, 48, 72, 96, 120, 144, 168, 192, and 216 and frozen at -20°C (total of 4 samples per time point at each storage condition). These samples were thawed and transferred to glass vials prior to their analysis by high-performance liquid chromatography electrospray ionization-tandem mass spectrometry and pH testing. All samples of dexmedetomidine 20 mcg/mL met stability criteria by retaining more than 90% of the initial concentration after 9 days under refrigeration and room temperature. There was no evidence of precipitation or color change during the study period. The pH reduced slightly over time under both refrigerated (5.7 to 4.5) and room temperature conditions (5.7 to 4.6). Dexmedetomidine solutions of 20 mcg/mL intended for subcutaneous use were stable in polyvinyl chloride bags containing 0.9% sodium chloride for 9 days under refrigeration and room temperature.