Effects of infusion tubing line lengths and syringe sizes on infusion system compliance: An experimental study using a syringe-type infusion pump at low flow rate

Abstract

Ideally, the flow delivery of an infusion system is proportional only to the rate of mechanical actuation of the syringe pump plunger. However, in the real world, overall infusion system compliance can vary with components such as tubing lines and syringes. With higher compliance, there may be greater chances of flow irregularity. In this experimental study, we investigated the effects of lengths of infusion lines and syringe sizes on the compliance of syringe pumps with low flow rate (2 ml·hr-1). In the first experiment, infusion system compliance was measured in various settings by occlusion-release. As the infusion tubing length and size of syringe increased, the time to reach each pressure was delayed and the infusion system compliance increased. The contributions to system compliance from syringes were significantly greater compared to those of extended infusion lines. In the second pre-occlusion alarm experiment, the occlusion alarm was delayed by 69.67 ± 3.98 minutes for the 50-ml syringe with a 560 cm infusion line set-up, requiring more attention when using a highly compliant infusion system. Thus, the performance of the syringe pump is affected by loaded syringe size and the length of the infusion line by changing the system compliance.