The performance of three portable infusion-pump devices set to deliver 2 mL/hr.

The performance of three portable infusion-pump devices set to deliver 2 mL/hr was studied. Portable infusion-pump devices (CADD-1, Paragon, and Singleday Infusor) were set to deliver 5% or 25% dextrose in water at 2 mL/hr for 24 hours at two environmental temperatures (25 and 35 degrees C). There were a total of 12 types of experimental runs, and each run was performed in triplicate. Flow rate accuracy and flow continuity were measured by a computerized gravimetric technique; effusate weights were measured and recorded at 30-second intervals for two hours at the beginning and two hours at the end of each run. Mean flow rates among the three devices did not differ significantly. Mean flow rate was significantly higher for the 5% dextrose solution than for the 25% dextrose solution, for the 35 degree C temperature than for the 25 degree C temperature, and during the first two hours of delivery than during the last two hours. The CADD-1 units showed an interruption of flow lasting about 30 seconds and recurring every 60 seconds; the other devices had fairly constant flow. Mean flow continuity differed significantly among the three devices. Mean flow continuity was significantly higher for the 5% dextrose solution and for the 25 degree C temperature. Flow continuity differed among three representative portable infusion-pump devices set to deliver 2 mL/hr, but flow rate accuracy did not. Fluid viscosity, environmental temperature, and elapsed time affected flow rate accuracy and flow continuity.