Laboratory evaluation of a new delivery system to improve patient compliance with chelation therapy

Abstract

As thalassaemia patients live longer, compliance with chelation therapy becomes more and more of a problem. Teenagers rebel against the continual need for treatment, and young adults with jobs, active social lives and families, find it hard to find the time to prepare and deliver their treatments. In an effort to find a solution to this problem, we evaluated a non-electronic, disposable pump (Infusor 5 ml/h, Baxter Healthcare) to determine its suitability for high dose desferrioxamine (DFO) infusions. We wanted an infusion time of 12 h to support overnight delivery in the patient's home. Because of DFOs viscosity, infusion times vary at different concentrations. We found the optimal prescription for total delivery within 12 h to be a dose of 70 mg/kg x patient's body weight diluted in constant volume of 40 ml of water for injection. Our tests were carried out in vitro and the results show that the 5 ml/h Infusor may be used to deliver high dose DFO chelation therapy within 12 h. The variability of the flow rate, dependent on the concentration of the solution, and the absence of a warning system, are more than compensated for by the simplicity of the pump.