Evaluation of the design and reliability of three elastomeric and one mechanical infusers

Abstract
Background. Disposable elastomeric and mechanical (spring mechanism) infusers with pre-fixed flow rates are principally used for long-term antibiotic therapy, chemotherapy, antiviral therapy, and chronic pain management. Methods. Three elastomeric pumps and one mechanical infuser pump are evaluated. The design and function are assessed using specific questionnaires elaborated for the pharmaceutical staff, nurses and patients, respectively. Several tests are performed to determine the flow accuracy and the influence of different parameters such as the temperature, the viscosity, the height, and the restrictor variability. Results. The functional tests show that the perfusion duration is shorter than that specified by the manufacturers, the restrictors are not homogeneous within a batch. However, the temperature of the regulator, the viscosity of the solution, and the height of the reservoir influence the flow rate. Conclusions. The ideal infuser should be small, light, unnoticeable, easy to fill, well identified and have a flow rate barely affected by external factors. None of the infusers has fulfilled all criteria, therefore the choice of infusers depends upon the nature of the treatment. The tested elastomeric infusers are adequate for 5-fluorouracil, but not for a treatment requiring a stable administration rate.